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FINAL EVERYTHING

STUDY
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What is the overarching theme of biology?
Evolution
How many themes are there that connect the concepts of biology?
7
What connects the concepts of biology?
Themes
1st Theme that connects the concepts of biology
New Properties Emerge at Each Level in the biological Hierarchy
2nd Theme that connects the concepts of biology
Organisms interact w/ their environments
3rd Theme that connects the concepts of biology
Structure and Function are correlated at all levels of biological organization
4th Theme that connects the concepts of biology
Cells are an organisms basic units of structure and function
5th theme that connects the concepts of biology
DNA is the heritable information in cells
6th theme that connects the concepts of biology?
Feedback mechanisms regulate biological systems
7th theme that connects the concepts of biology?
Evolution accounts for the unity and diversity of life
What is the general concept of biology that all themes are connected to
Scientists use two forms of inquiry in their study of nature
Scientists use two forms of inquiry in their study of nature
-Discovery Science
-Hypothesis-based science
Theme 1: New properties emerge at each level in the biological heirarchy (4 concepts)
-Levels of organization
-Emergent Properties
-Reductionism
-Systems Biology
Theme 2: Organisms interact with their environments (2 concepts)
-Ecosystem Dynamics
-Energy conversion
What are the two forms of feedback that regulate biological systems?
Negative & Positive
What is positive feedback?
means that as more of a product accumulates, the process that creates it speeds up and more of the product is produced
What is negative feedback?
means that as more of a product accumulates, the process that creates it slows & less of the product is produced
Theme 7: Evolution accounts for the unity and diversity of live (3 concepts)
-Organizations of life
-Three domains of life
-Charles Darwin & the theory of natural selection
Three Domains of Life
Bacteria
Archaea
Eukarya
What is evolution?
Process of change that has transformed life on earth
What is biology?
Scientific study of life
We recognize life by what living organisms....
DO!
T/F Evolution makes sense of everthing we know about living organisms?
True!
The study of life can be divided into different ______.
Levels of biological organization
Levels of biological organization
1 biosphere
2 ecosystemes
3 communities
4 populations
5 organisms
6 organs and organ systems
7 tissues
8 cells
9 organelles
10 molecules
What are emergent properties?
Properties that result from the arrangement and interaction of parts within a system
Reductionism
reduction of complex systems to simpler components that are more manageable to study
An understanding of biology balances reductionism with the study of...
emergent properties
What is a system?
A combination of components that function together
What does systems biology do?
constructs models for the dynamic behavior of whole biological systems
T/F Every organism interacts with its environment and other organisms, not including nonliving facts
FALSE (does include nonliving factors)
Both organisms and their environments are affected by...
the interactions between them
Both organisms and their environments are affected by the interactions between them. This is considered the exchange of..
matter & energy
Ecosystem Dynamics' 2 major processes:
1. cycling of nutrients, in which materials acquired by plants eventually return to the soil
2. The flow of energy, from sunlight to producers and consumers
Work requires..
source of energy
Energy can be stored how..
in many different forms such as light, chemical, kinetic, potential, and thermal
The energy exchange between and organism and its environment often involves...
energy transformations
Energy flows _____ an ecosystem
through
Energy usually enters as... and leaves as...
enters as light, leaves as heat
T/F Structure and function of living organisms are closely related
True
(example: a leaf is thin & flat, maximizing the capture of light by chloroplasts)
What is the basic unit of life?
Cells
The ____ is the lowest level of organization that can perform all activities required for life.
cell
All cells....
-Are enclosed by a membrane
-Use DNA as their genetic info
Two groups of cells..
Eukaryotic & Prokaryotic
Eukaryotic
cells that have a nucleus
Prokaryotic
cells that do not have a nucleus
What is the heritable information in cells?
DNA
What do chromosomes contain?
cell's genetic material in the form of DNA
Chromosomes contain cell's genetic material in the form of what?
DNA
What are genes?
units of inheritance that transmit information from parents to offspring
Genes are composed of..
DNA
What is taxonomy
Branch of biology that names and classifies species into groups of increasing size
What the broadest units of classification?
Domains followed by Kingdoms
What domain(s) comprise all prokaryotes?
Domain Bacteria & Domain Archaea
What domain(s) include all eukaryotes?
Domain Eukarya
Charles Darwin is known for what theory?
Theory of Natural Selection
What did Darwin observe?
-Individuals in population have traits that vary
-Many of these traits are heritable (passed on)
-More offspring are produced than survive
-Competition is inevitable
-Species generally suit their environment
Darwin inferred from his observations that:
-Individuals that are best suited to their environment are more likely to survive & reproduce
-Over time, more individuals in a population will have the advantageous traits
Natural environments _____ for beneficial traits.
Select
Evolutionary relationships are often illustrated with what kind of diagrams that show ancestors and their descendants?
tree-like diagrams
What is discovery science?
describes natural structures and processes
Discovery science is based on two things
-observation
-analysis of data
What is data?
recorded observations or items of information
Two types of data
Qualitative
Quantitative
What's the difference between qualitative and quantitative data?
qualitative - descriptions rather than measurements
quantitative - recorded measurements
Scientists use what to arrive at conclusions?
Inductive reasoning
Inductive Reasoning
deriving general principles from particular facts or instances (Sun always rises in the east, objects fall to the ground).
Hypotheses are..
Hypothetical explanations which are proposed from observations that lead us to ask questions
What is a hypothesis?
tentative answer to a well-framed question
Every hypothesis must be...
testable & falsifiable
Falsifiable
capable of being tested (verified or falsified) by experiment or observation; capable of being disproved
Deductive Reasoning does what?
uses general premises to make specific predictions (if organisms are made of cells, and humans are organisms, then humans are composed of cells)
Scientific Method
1. Observations/Define problem
2. Collect information
3. Form Hypothesis
4. Test hypothesis/Experiment
5. Make conclusions based on testing
6. Report results
What is a controlled experiment?
One that is designed to compare an experimental group with a control group
Controlled experiments are ones that are designed to compare an experimental group with a....
control group
What is the independent variable of an experiment?
The cause (cause/effect)
What is the dependent variable of an experiment?
The effect (cause/effect)
T/F Scientific Theories are broader in scope than a hypothesis
True!
Scientific Theories are characterized by these 3 characteristics..
-Broader in scope than a hypothesis
-Very general
-Supported by a large body of evidence in comparison to a hypothesis
what is matter?
anything that takes up space & has mass
3 forms of Matter that build off of eachother
1. Elements
2. Atoms (smallest unit of element)
3. Isotopes (two atoms of an element have different number of neutrons)
What are elements?
Substances that cannot be broken down into simpler substances
4 most important elements?
1. Oxygen
2. Carbon
3. Nitrogen
4. Hydrogen
Trace Elements
Elements required by an organism in only extremely small quantities
What are atoms?
Smallest unit of an element
Subatomic particles of an atom
-Protons (positive charge)
-Neutrons (neutral)
-Electrons (negative charge)
Atomic nucleus consists of..
protons & neutrons
Are protons and neutrons almost identical in mass?
yes
What is a Dalton?
Atomic Mass Unit (AMU)
Electrons weigh _____ than protons & neutrons
ALOT LESS
Orbitals/Shells/Clouds...
area where electrons are found
What determines chemical behavior of an atom?
number and arrangement of electrons
Valence
the number of electrons in the outermost energy level of an atom
What makes an atom neutral?
# protons = # electrons
Atomic number indicates...
number of protons
Atomic Mass (Mass number) indicates...
sum of protons and neutrons
Isotopes are...
two atoms of the same element that differ in number of neutrons
what are radioactive isotopes
the nucleus decays spontaneously, giving off particles and energy
Two or more atoms combine chemically to form...
molecules or compounds
Molecules are...
two or more atoms of the same element
Compounds are..
two or more atoms bonded but by different elements
T/F a compound has characteristics similar to those of its element's
FALSE!!
Chemical formulas describe...
chemical composition of a compound
Chemical equation...
describes chemical reaction between atoms and compounds
4 Kinds of Chemical Bonds:
-Covalent Bonds
-Ionic Bonds
-Hydrogen Bonds
-Van der Waals Interactions
What are covalent bonds?
-Sharing of electrons
-Strongest chemical bonds in nature
What is the strongest chemical bond in nature?
COVALENT BONDS
Covalent bonds can be one of these two things?
polar/nonpolar
Polar molecules:
-unequal sharing of electrons
-give/take of electrons rather than share
Electronegativity
The ability of an atom to attract electrons when the atom is in a compound
Nonpolar molecules:
-electrons are equally shared
Ionic bonds are when..
one atom donates electrons to another
When an atom becomes charged, it forms an..
ion
Cations are..
positively charged ions
ion
a particle that is electrically charged (positive or negative)
Anions are...
negatively charged ions
T/F ionic compounds or salts easily dissociate in water
True
Hydrogen bonds form when...
a hydrogen atom that is covalently bonded to an electronegative atom is also attracted to another electronegative atom
Are hydrogen bonds strong or weak?
VERY WEAK!!
Hydrogen bonds are very important in...
biological systems
Van der Waals Interactions
weak and occur only when atoms and molecules are very close together
Are Van der Waals interactions weak or strong bonds?
Very weak chemical bonds
Van der Waals interactions occur ONLY when...
atoms and non-polar molecules are very close together, due to regions of slightly opposite charge
Emergent properties
new properties that emerge with each step upward in the hierarchy of life, owing to the arrangement and interactions of parts as complexity increases
Molecules are drawn flat... are they flat realistically?
No, 3-dimensional
Molecules 3D shape determines...
biological function
Hormones have certain shapes that they are...
recognized by specific cells in your body
Do antibodies and antigens keep us healthy or make us sick?
Keep us healthy
Enzymes can only work in what form?
3D form
Lock and Key Theory (explain)
Deals with enzymes; there's always a unique way that something must fit, and it doesn't fit, it will not work
Antibodies are what kind of macromolecule?
they are proteins
What does an antibody do?
Recognizes things you've been exposed to and immediately deactivates it.
In chemical reactions, do all atoms of the reactants have to be accounted for?
Yes, balanced equations
Reversible reactions are what..
have to do with chemical reactions; proceed both ways
(3H2 + N2 <=> 2NH3)
Chemical equilibrium is what?
The point at which reactions offset one another
When talking about the chemical equilibrium, the _______ remains the same, but the _____ goes forward and backward.
concentration remains the same; reaction goes forward and backward
All life forms require water. T/F
True!
All cells are surrounded by what chemical compound?
Water (h2o)
Cells are mostly composed of...
water
A liquid at body temperature is good for two reasons
it can flow freely & it is excellent for transportation of solutes
Water is nonpolar or polar?
POLAR!!
Water forms what kinds of bonds with eachother?
Hydrogen bonds
Hydrogen bonds are very weak bonds unless...
alot of hydrogen is used
Emergent properties of water:
1. Cohesive behavior
2. Ability to moderate temperature (never a rapid increase or decrease in temperature)
3. Expansion when frozen
4. Versatile solvent
Cohesion is when..
molecules are attracted to molecules
Cohesion is very important for...
plants
During cohesion, water molecules stick together due to what kind of bonds?
Hydrogen bonds
Cohesion helps transport water in which way in plants?
upward
Adhesion is what?
Molecules are attracted to the walls of the cell
Surface tension is related to what?
Cohesion
Surface tension is what?
a force to pull liquid inward; or how difficult it is to break the surface of a liquid
Water has a (greater or lower) surface tension that most liquids?
Greater
All hydrogen bonds make almost a film... explain.
Hydrogen bonds form a film that is an invisible coat on the surface of water molecules
Water can absorb or release a large amount of heat with what kind of change in temperature?
Slight change
T/F Water acts as a heat bank (heat source/heat sink)
True
Energy is..
the capacity to do work
Where is potential energy located?
It is STORED in bonds that hold atoms together in all matter.
Kinetic energy is..
energy in motion
Why do all atoms and molecules have kinetic energy?
Because they are always moving
Heat (definition)
measure of the total quantity of kinetic energy due to molecular motion
What measures the intensity of heat?
Temperature
Specific Heat (Definition)
Amount of heat that must be absorbed or lost for 1 gram of that substance to change its temperature by 1 degree C
Why does a pot get hot before the water even begins boiling?
Concept of specific heat.
Iron gets hotter because it has a lower specific heat than water
What has a high or low specific heat?
Extremely high
Why can water resist change in temperature?
Specific Heat is so high for water
Water has unusually high specific heat.. this is due to what kind of bonds?
Hydrogen bonds
Why is specific heat so important?
Affects climate and oceans;
coast gets cooler in summer because water absorbs heat. coast gets warmer in winter, because water is giving off heat
What is evaporation?
transformation of a substance from a liquid to a gas
Heat a liquid must absorb for 1 gram to be converted to gas, is what
heat of vaporization
As a liquid evaporates, its remaining surface cools, a process known as..
evaporative cooling
(in coffee, surface is cooler than bottom)
When you sweat, you release molecules that are hot first to cool you down. This is an example of
evaporative cooling
Evaporative cooling of water helps stabilize __________ in organisms and bodies of water.
temperatures
Water is (more/less) dense as a solid than a liquid.
less dense
(ice floats)
Typically substances contract as they solidify, but water expands.. Why is this?
Hydrogen Bonds!!
When water freezes, molecules are no long moving fast enough to..
break hydrogen bonds
Hydrogen bonds form a _______ when water is frozen.
Latisse
What is the solvent of life?
Water
Solvent is the..
liquid that dissolves substance
Solute is the..
substance being dissolved
Water is a versatile solvent due to its..
polarity
Water molecules only like other molecules if the other molecules are...
polar or charged
Hydrophilic means
polar bonds, water loving (cellulose)
Hydrophobic
nonpolar bonds, fear of water (wax & oil)
Hydrogen Ions are one of the most important ions in the body T/F
True!
Acids are any molecules that..
can donate hydrogen ions in aqueous solutions, have more hydrogen ions than pure water
Bases are any molcules that..
can accept hydrogen ions in aqueous solutions, has fewer hydrogen ions than pure water
pH scale is a measure of..
hydrogen ion concentration in a solution
What is a buffer?
Substances that minimize changes in pH that might occur when acids or bases are added.
Biological fluids contain buffers. T/F
True!
Carbon is the universal medium for life. T/F
False! (water)
Cells are mostly water.. the rest are what kind of compounds?
Carbon-Based compounds
4 Major Carbon-Based Compounds
Proteins
Carbohydrates
Lipids
Fats
Carbon is unparalleled in its ability to form what kind of molecules?
Large, complex and diverse molecules
Organic chemistry is..
the study of compounds that contain carbon
Organic compounds contain what element..
carbon
Most organic compounds contain what atoms?
Hydrogen Atoms
The idea that organic compounds arise only in organisms, which was later disproved.
Vitalism
Who disproved vitalism?
Stanley Miller
The view that all natural phenomena are governed by physical and chemical laws is what..
Mechanism
Carbons can form kind of bonds and how many?
4 covalent bonds
Tetravalence forms what kind of molecules..
Large complex molecules
The valences of what 4 atoms are the "building code" that governs the architecture of living molecules.
carbon, hydrogen, oxygen, and nitrogen
Carbon chains form skeletons of most organic molecules.. this is called the
Carbon Skeleton
Do carbon chains in carbon skeleton vary in length?
Yes
Can carbon chains in carbon skeleton be branched, unbranched, or both?
Both unbranched and branched
Can carbon chains have double bonds?
Yes
Can carbon chains form ring structures?
Yes
Organic molecules consisting of only carbon and hydrogen are called..
Hydrocarbons
Can hydrocarbons undergo reactions that release a large amount of energy?
Yes
Can hydrocarbons dissolve in water?
No
Are hydrocarbon bonds polar or nonpolar?
Nonpolar
Compounds with the same molecular formula but different structures and properties are what..
isomers
3 kinds of isomers:
-Structural isomers
-Geometric Isomers
-Enantiomers
Isomers that have different covalent arrangements of their atoms..
structural isomers
Isomers that have the same covalent arrangements but differ in spatial arrangements.
Geometric isomers
Isomers that are mirror images of eachother
Enantiomers
Simplest organic molecules are..
Hydrocarbons
What makes the framework for more complex organic molecules?
Hydrocarbons
Functional groups contribute to a molecules function by affecting its'....
shape
Functional groups are indirectly or directly involved in chemical reactions?
directly
ATP stands for
Adenosine Triphosphate
All living things are made up of four classes of large biological molecules:
-Carbohydrates
-Lipids
-Proteins
-Nucleic Acids
Large molecules composed of thousands of covalently connected atoms are...
Macromolecules
What is a monomer?
Small building block molecule for macromolecule
What is a polymer?
Long molecule consisting of many similar building blocks (monomers) in macromolecules
Condensation Reactions aka...
Dehydration Synthesis
Occurs when two monomers bond together through the loss of a water molecule
condensation reaction or dehydration synthesis
Macromolecules that speed up dehydration process as well other biological reactions are..
Enzymes
You would make a polymer by
Dehydration synthesis or Condensation Reaction
You would break down a polymer by
Hydrolysis
Bonds between monomers are broken by addition of water molecules is & is the reverse of dehydration synthesis..
Hydrolysis
Enzymes only speed up dehydration synthesis but not hydrolysis. t/f
FALSE
T/F Each cell has thousands of different kinds of macromolecules
true!
Macromolecules vary among cells of an organism, vary ____ within a species, and even ______ between species.
More; More
Can an immense variety of polymers be built from a small set of polymers?
Yes!
What do carbohydrates include and contain?
Sugars & the polymers of sugar; containing C, H, & O
Monosaccharides are...
-Simple sugars
-Glucose most common
-Major fuel for cells
-Raw material for building molecules
Disaccharides forms when..
formed when a dehydration reaction joins two monosaccharides
In Disaccharides, the covalent bonds are called..
Glycosidic linkage
The polymers of sugars are...
polysaccharides
Polysaccharides
-have storage roles
-have structural roles
Structure and function of a polysaccharide are determined by..
its sugar monomers and the positions of glycosidic linkages
Storage polysaccharides are what in animals and plants?
Plants- starch
Animals - Glycogen
Structural Polysaccharides
Cellulose which is a component of cell walls
Do lipids form polymers?
NO
Do lipids have attraction to water?
No
Lipids are made up of mostly..
Hydrocarbons (nonpolar)
Most important lipids are..
fats
phospholipids
steroids
What is constructed from glycerol and fatty acids?
Fats
3-Carbon alcohol with a hydroxyl group attached to each carbon is what..
Glycerol
What consists of a carboxyl group attached to a long carbon skeleton?
Fatty acid
Saturated fatty acids have the _______ number of hydrogen atoms possible and no ______ bonds.
maximum ; double
Saturated fats are (solid/liquid/gas) at room temp.
Solid
Unsaturated fatty acids have one or more ______ bonds.
Double
Unsaturated fats are (solid/liquid/gas) at room temp.
Liquid
What is the major function of fats?
Energy Storage
Humans and other mammals store fat in what kind of cells?
Adipose
______ tissue cushions vital organs and insulates the body.
Adipose
Phospholipids consists of...
two fatty acids and a phosphate group attached to a glycerol
In water, phospholipids self assemble into a...
bilayer
Hydrophobic tails of phospholipids face or look away from eachother?
Face eachother
Major component of all cell membranes
Phospholipids
Lipids characterized by carbon skeleton consisting of 4 fused rings
Steroids
What is the important steroid that is a component in all animal cell membranes
Cholesterol
Proteins.. overview
-half of dry mass cells
- many functions
-enzymes speed up chemical reactions
-structural support
-storage
-transport
-cellular communication
-movement
-cellular defense
Enzymes act as a what to speed up chemical reactions
catalyst
Can enzymes perform their functions repeatedly?
Yes
What are the large polymers built from the same set of 20 amino acids?
Proteins
Can proteins consist of one or more polypeptides?
Yes
What gives proteins their unique functions?
how they are folded and coiled into a specific 3D structure
Organic molecules with carboxyl and amino groups are..
Amino acids
Amino acids differ in their properties due to differing side chains called..
R groups
What are amino acids linked by?
Polypeptide bonds
What is a polypeptide?
polymer of amino acids
What determinds a proteins 3d structure?
sequence of amino acids
4 Levels of Protein Structure
1. Primary Structure
2. Secondary Structure
3. Tertiary Structure
4. Quaternary structure
Primary structure of a protein
sequence of amino acids
Secondary structure of a protein
coils and folds in polypeptide chain
Tertiary structure of a protein
interactions among various side groups (R groups)
Quaternary structure of a protein
when protein consists of multiple polypeptide chains
Secondary structure of a protein: a coil is called a what? a folded structure is called a what?
coil - Alpha Helix
folded - Beta Pleated Sheet
Loss of a proteins native structure is called..
Denaturation
Chaperonins are..
proteins molecules that assist proper folding of other proteins (aka chaperone proteins)
What stores and transmits hereditary information?
Nucleic Acids
DNA provides direction for..
it's own replication
DNA directs synthesis of mRNA and through mRNA controls...
Protein Synthesis
Protein synthesis occurs where in the cell?
Ribosomes
Each nucleotide consists of:
1. Pentose Sugar
2. Phosphate Group
3. Nitrogenous Base
Portion of a nucleotide without the phosphate group is called the...
Nucleoside
2 Families of Nitrogenous Bases:
Pyrimidines & Purines
Pyrimidines
cytosine, thymine, uracil
Purines
adenine and guanine
Nucleotide polymers are joined by what kind of bond?
Phosphodiester bonds
T/F Cells have a high surface area to cell volume ratio
True
Prokaryotic Cells Characteristics
-single cells
-has plasma membrane
-has DNA but no nucleus
-No membrane bound organelles
-Simpler
-Smaller
Eukaryotic Cells Characteristics
-Single or multicellular
-has plasma membrane
-has DNA in nucleus
-has membrane bound organelles
-more complex
-larger
Selective Barrier:
allows passage of oxygen, nutrients, and waste to service volume of every cell
Particles made of ribosomal RNA and protein
Ribosomes
What organelle carries out protein synthesis?
Ribosomes
Endomembrane system regulates..
protein traffic & performs metabolic functions in the cell
Components of endomembrane system?
-nuclear envelope
-endoplasmic reticulum
-golgi apparatus
-lysosomes
-vacuoles
-plasma membrane
Endoplasmic Reticulum is continous with..
Nuclear Envelope
Smooth ER
lacks ribosomes
Rough ER
ribosomes stud the surface
Smooth ER functions
Synthesizes lipids,
Metabolizes carbohydrates
Detoxifies poison
Stores Calcium
Rough ER functions
secrete glycoproteins
distribute transport vesicles
membrane factory for cell
"Shipping & Receiving center" (organelle)
golgi apparatus
Golgi apparatus functions
Modifies products of the ER
Manufactures certain macromolecules
Sorts & Packages materials into transport vesicles
"Digestive Compartments" (organelle)
Lysosomes
Lysosomal enzymes can hydrolyze..
proteins, fats, polysaccharides, and nucleic acids
"Diverse Maintenance Compartments" (organelle)
Vacuoles
"Protein Factory" (organelle)
Ribosomes
What organelle contains most of the cells genes
Nucleus
What organelle encloses the nucleus, separating it from the cytoplasm?
Nuclear Envelope
Nuclear membrane is a double membrane, each consisting of..
a lipid bilayer
In nucleus, DNA & proteins form genetic material called..
Chromatin
Chromatin condenses to form..
Chromosomes
This organelle is located within the nucleus and is the site of ribosomal RNA synthesis
Nucleolus
Ribosomes carry out protein synthesis in two locations..
-in cytosol (free ribosomes)
-on the outside of ER or the nuclear envelope (bound ribosomes)
Components of endomembrane system:
-nuclear envelope
-Endoplasmic reticulum
-golgi apparatus
-lysosomes
-vacuoles
-plasma membrane
What holds organic compounds and water in plant cells?
Central vacuoles
Sites of cellular respiration, a metabolic process that generates ATP is what organelle?
Mitochondria
What organelle is the site of photosynthesis?
Chloroplasts
Mitochondria & Chloroplasts characteristics
-not part of endomembrane system
-double membraned
-have proteins made by free ribosomes
-contain their own DNA
Some metabolic steps of cellular respiration are catalyzed in the..
mitochondrial matrix
What do chloroplasts consists of?
Thylakoids (membranous sacs) & Stroma (internal fluid)
Thylakoids stacked forms what..
a granum
Network of fibers extending through cytoplasm
Cytoskeleton
Organizes cell's structures and activites, anchoring many organelles
Cytoskeleton
Extracellular structures in plants and animals are..
Cell walls - plants
extracellular matrix - animals
Do animals have cell walls?
No
Animals lack cell walls but are covered by...
extracellular matrix
Nucleic acids are made of polymers or monomers?
monomers
Nucleic acids are made of monomers called ___________.
nucleotides
List the 3 parts that a nucleotide consists of.
1. nitrogenous base
2. pentose sugar
3. phosphate group
Phosphate group's molecule consists of what two elements?
Phosphorous & Oxygen
Pentose sugar molecule consists of what
5'C bond from phosphate group right to sugar, CH₂, O, 3'C to the right of the sugar
Nitrogenous base is connected to what in a nucleic acid in terms of molecules?
Sugar is connected below the nitrogenous base
Synonym for nucleic acid
Polynucleotide
What are the two families of nitrogenous bases?
Pyrimidines & Purines
Pyrimidines consist of what?
Cytosine
Thymine
Uracil
Purines consist of what?
Adenine & Guanine
Difference in molecular structure between pyrimidines and purines.
Pyrimidines have one one octagon
Purines have two octagons, one being C₂N₂HCH
What are the two types of nucleotide monomers?
DNA & RNA
DNA has what kind of sugar?
Deoxyribose
RNA has what kind of sugar?
Ribose
In a DNA molecule, there are how many hydrogens by themselves?
3
In a RNA molecule, there are how many hydrogens by themselves?
2
All nitrogenous bases are either _______ or ________.
Pyrimidines or Purines
All sugar molecules in DNA/RNA are either _________ or ________.
Deoxyribose (DNA)
or
Ribose (RNA)
Polynucleotide
Lots of nucleotide polymers linked together
Phosphodiester Bonds
covalent bonds that link nucleotide polymers together when forming a polynucleotide
Phosphodiester bonds form between the ____ group on the ___ carbon of one nucleotide and the ____ group on the ___ carbon on the next.
Phosphodiester bonds form between the [-OH GROUP] on the [3'] carbon of one nucleotide and the [PHOSPHATE] group on the [5'] carbon on the next.
DNA has what kind of helix?
Double Helix
What are the backbones of a DNA double helix?
sides of the ladder.
run in opposite directions
(5' --> 3' & 3' --> 5')
In DNA double helix, the two backbones run in opposite 5' --> 3' directions from eachother. This arrangement is referred to as _________.
Antiparallel
Nitrogenous bases in DNA pair up and form what kind of bonds?
Hydrogen bonds
What nitrogenous bases always pair up together?
Adenine (A) with Thymine (T)
&
Guanine (G) with Cytosine (C)
DNA has _________ sugar and RNA has __________ sugar.
Deoxyribose (DNA)
Ribose (RNA)
DNA nitrogenous bases
Adenine
Cytosine
Guanine
Thymine
RNA nitrogenous bases
Adenine
Cytosine
Guanine
Uracil
There is one base that changes depending on whether DNA or RNA is being used. In DNA it is ________ & RNA it is ________.
Thymine (DNA) & Uracic (RNA)
DNA is ________ stranded
double
RNA is ________ stranded.
single
Each strand of DNA acts as a ___________ for building a new strand in replication.
template
Summarize DNA replication.
1. Parent molecule unwinds
2. Two new daughter strands are formed
3. Daughter DNA molecules are formed each consisting of one parental strand and one new strand.
Semiconservative Model of Replication
After replication, each daughter molecule will have one old strand ("conserved" from the parent molecule) and one newly made strand
Copying of DNA is remarkable because of its ______ and _______.
Speed & Accuracy
More than a(n) _____ ____ and other ______ participate in DNA replication.
more than a dozen enzymes
&
other proteins
DNA replication begins at special sites called...
Origins of Replication
When DNA replication begins at the origins of replications, what happens?
2 DNA strands are separated and form a replication "bubble"
(DNA Replication) Eukaryotic Chromosomes contain how many origins of replication?
100-1000s of origins of replication
(DNA Replication) Prokaryotic chromosomes contain how many origins of replication?
1
(DNA Replication)
Replication proceeds in _____ directions from each origin, until the _____ _____ is copied.
Replication proceeds in (BOTH) directions from each origin, until the (ENTIRE MOLECULE) is copied.
At the end of each replication bubble is a....
Replication Fork
Replication Fork
Y-shaped region where new DNA strands are elongating
Helicases
enzymes that untwist the double helix at the replications forks
Single-Strand Binding Protein
Stabilizes and binds to single-stranded DNA until it can be used as a template
Topoisomerase
corrects "overwinding" ahead of replication forks by breaking, swiveling, and rejoining DNA strands
DNA Polymerase
enzyme that catalyzes the successive addition of each new nucleotide to the growing chain
DNA polymerases can or cannot initiate synthesis of a polynucleotide?
Cannot
DNA Polymerase can only do one thing. What is it?
They can only add nucleotides to the 3' end.
The initial nucleotide strand is a...
short RNA primer
Primase
enzyme that starts an RNA chain from scratch and adds RNA nucleotides one at a time using the parental DNA as a template
The primer in DNA replication is short or long?
short
How many nucleotides are on a primer usually?
5-10 nucleotides long
3' end serves as the...
starting point for the new DNA strand
What enzymes catalyzes the elongation of the new DNA at a replication fork?
DNA polymerases
Most DNA polymerases require two things. What are they?
A Primer & A DNA template strand
The rate of elongation during DNA replication is about what per second in bacteria and what per second in human cells?
500 nucleotides per second (bacteria)
50 nucleotides per second (humans)
Each nucleotide that is added to a growing DNA strand is a....
Nucleoside Triphosphate
dATP
supplies adenine to DNA and is similar to the ATP of energy metabolism
Difference in dATP sugar and ATP sugar.
dATP - deoxyribose
ATP - ribose
As each monomer of dATP joins the DNA strand, it loses ________ as a molecule of _______.
it loses (2 phosphate groups) as a molecule of (pyrophosphate)
What affects replication in DNA's double helix?
The antiparallel structure
DNA polymerases add nucleotides only to what end of a growin strand?
3'
Because DNA polymerases add nucleotides only to the free 3' end of a growing strand. Because of this, what happens?
New DNA strands can elongate only in the 5' to 3' direction
Along one template strand of DNA, the DNA polymerase synthesizes a ______ _______ continuously, moving toward the what?
Leading Strand which move toward the Replication fork
To elongate the lagging strand, DNA polymerase must work in what direction in relation to the replication fork.
away from the replication fork
The lagging strand in DNA Replication is synthesized is synthesized as a series of segments called what?
Okazaki Fragments
Okazaki fragments are joined together by what?
DNA Ligase
Helicase
Protein which unwinds parental double helix at replication forks
Single-Strand binding protein
Protein that binds to and stabilizes single-stranded DNA until it can be used as a template
Topoisomerase
Protein that relieves "overwinding" strain ahead of replication forks by breaking, swiveling, and rejoining DNA strands
Primase
Protein that synthesizes an RNA primer at the 5' end of leading strand and of each Okazaki fragment of the laggin strand
DNA pol III
Protein using parental DNA as a template which synthesizes new DNA strands by covalently adding nucleotides to the 3' end of a pre-existing DNA strand or RNA primer
DNA pol I
Protein that removes RNA nucleotides of primer from 5' end and replaces them with DNA nucleotides
DNA Ligase
Protein that joins 3' end of DNA that replaces primer to rest of leading strand and joins Okazaki fragments of lagging strand
The proteins that participate in DNA replication form a large complex called what?
DNA replication machine
The DNA replication machine is probably _____ during the replication process.
stationary
Recent studies support a model in which DNA polymerase molecules do what?
Reel in parental DNA and force out newly made daughter DNA molecules
DNA polymerases _______ newly made DNA, doing what?
proofread newly made DNA, replacing any incorrect nucleotides
Mismatch Repair
The cellular process that uses special enzymes to fix incorrectly paired nucleotides.
DNA can be damaged by what? Give examples.
Chemicals
examples: radioactive emissions, x-rays, UV light, and certain molecules in cigarette smoke, etc.
What happens in nucleotide excision repair?
a nuclease cuts out and replaces damaged stretches of DNA
Nuclease
An enzyme that cuts DNA or RNA, either removing one or a few bases or hydrolyzing the DNA or RNA completely into its component nucleotides.
Limitations of DNA polymerase creates problems for what?
Linear DNA of eukaryotic chromosomes
The usual replication machinery provides ___ way(s) to complete the 5' ends.
NO way
Repeated rounds of replication produce ____ DNA molecules.
Shorter
Telomeres
nucleotide sequences at the end of eukaryotic chromosomal DNA
Do telomeres prevent the shortening of DNA molecules?
No.
Although telomeresDO NOT prevent the shortening of DNA molecules, they DO...
postpone the erosion of genes near the ends of DNA molecules
It has been proposed that the shortening of telomeres is connected to what?
aging.
If chromosomes of germ cells became shorter in every cell cycle, what would happen?
essential genes would eventually be missing from the gametes they produce
An enzyme called _______ catalyzes the lengthening of telomeres in germ cells.
Telomerase
The shortening of telomeres might protect cells from...
cancerous growth by limiting the number of cell divisions
There is evidence of telomerase activity in...
cancer cells, which may allow cancer cells to persist.
Chromosome organization in a bacterial chromosome..
circular DNA molecule associated with a small amount of protein
Chromosome organization in eukaryotic chromosomes..
Linear DNA molecules associated with a large amount of protein.
In a bacterium, the DNA is "______".
supercoiled
In a bacterium, the DNA is "supercoiled" and found in a region of the cell called the..
nucleoid
Chromatin
complex of DNA and protein, found in nucleus of eukaryotic cells
Histones
proteins that are responsible for the first level of DNA packing in chromatin.
Chromatin is organized into..
fibers
10-nm fiber
DNA winds around histones making nucleosome "beads" on a string.
30-nm fiber
Interactions between nucleosomes cause the thin fiber to coil or fold into this thicker fiber.
300-nm fiber
The 30-nm fiber forms looped domains that attach to proteins
Looped domains
the 30 nm fiber forms these loops which attach to a chromosome scaffold made of protiens - 300 nm fiber.
Metaphase chromosome
The looped domains coil further
The width of a chromatid is 700 nm
Information content of DNA is in the form of....
genes.
Genes
specific sequences of nucleotides
Proteins are the links between what?
Genotype & phenotype
Gene expression
process by which DNA directs protein synthesis, uncludes two stages.
2 Stages of Gene Expression
1. Transcription
2. Translation
RNA is the intermediate between what..
genes and the proteins for which they code
Transcription
synthesis of RNA under the direction of DNA
Transcription produces what?
mRNA (messenger RNA)
Translation
synthesis of a polypeptide under the direction of mRNA
Ribosomes
sites of translation
In prokaryotes, mRNA produced by transcription is what...
immediately translated without more processing
In eukaryotes, the __________ ________ separates transcription from translation.
Nuclear envelope
In eukaryotes, the nuclear envelope separates what?
transcription from translation
Eukaryotic RNA transcripts are modified through what to yield finished mRNA.
RNA processing
mRNA moves out of what organelle?
cytoplasm
Primary Transcript
initial RNA transcript from any gene
What is the concept that cells are governed by a cellular chain of command: DNA -> RNA -> Protein
Central Dogma
The central dogma is the concept that cells are governed by a cellular chain of command which is what?
DNA -> RNA -> Protein
Genetic Code
sequence of nucleotides that specifies the amino acid sequence of a protein
How are the instructions for assembling amino acids into proteins encoded into DNA?
Genetic Code
There are __ amino acids, but there are only ___ nucleotide bases in DNA.
20 amino acids
4 nucleotide bases in DNA
Flow of information from gene to protein based on a triplet code called...
codons
Triplet code
the normal version of the genetic code in which a sequence of three nucleotides codes for the synthesis of a specific amino acid
Codons are..
non-overlapping, three-nucleotide words
Template strand provides..
template for sequence of nucleotides in the mRNA transcript
During what stage does the template strand provide a template for the sequence of nucleotides in the mRNA transcript.
Transcription
During what stage does the mRNA base triplets or codons get read in the 5' to 3' direction
Translation
Codons
mRNA base triplets
What direction are the codons read during translation?
5' to 3' direction
Each codon does what?
specifies the amino acid to be placed at the corresponding position along a polypeptide.
Each codon specifies the amino acid to be placed at the __________ position along a polypeptide.
Corresponding
All 64 codons were deciphered by when?
mid-1960s
Of the 64 triplets (codons), how many are code for amino acids?
61
Of the 64 triplets (codons), there are three that do what?
there are 3 codons that are "stop" signals to end translation
The genetic code is ______ but not ______
redundant but not ambiguous
Can any codon specify more than one amino acid?
No. No codons specifies more than one amino acid.
Codons must be read in the correct....
reading frame
Reading frame
correct groupings
Why must codons be read in the correct reading frame?
in order for the specified polypeptide to be produced
The genetic code is nearly ________.
Universal
The genetic code is nearly universal shared by the ______ ________ to the _____ _______.
shared by the simplest bacteria to the most complex animals
Genes can be transcribed and translated after what?
after being transplanted from one species to another
Example of expression of genes from different species..
-tobacco plant expressing firefly gene
-pig expressing a jellyfish gene
RNA polymerase
catalyzes the synthesis of mRNA
RNA polymerase catalyzes the synthesis of mRNA by doing 2 things..
1. pries the DNA strands apart
2. hooks together the RNA nucleotides
Base-pairing rules (RNA)
Guanine with Cytosine
Adenine with Uracil
The DNA sequence where RNA polymerase attaches is called the...
promoter
Promoter
DNA sequence where RNA polymerase attaches
The stretch of DNA that is transcribed is called a...
transcription unit
Transcription unit
Stretch of DNA that is transcribed
Three Stages of Transcription (RNA)
1. RNA Polymerase Binding & Initiation of Transcription
2. Elongation of the RNA Strand
3. Termination of Transcription
During Initiation stage of transcription of RNA, what first signals the initiation of RNA synthesis?
Promoters
Transcription Factors
help bind RNA polymerase and initiation of transcription
Transcription initiation complex
the completed assembly of transcription factors and RNA polymerase bound to the promoter.
The completed assembly of transcription factors and RNA polymerase bound to the promoter is called the..
Transcription initiation complex
What promoter is crucial in forming the initiation complex in eukaryotes?
TATA box
During the elongation of the RNA strand, RNA polymerase moves along the DNA which does what?
untwists the double helix
During elongation of the RNA Strand, transcription progresses at what rate in eukaryotes?
40 nucleotides per second
Can a gene be transcribed simultaneously? If so, by what?
Yes but only by several RNA polymerases
Mechanisms of termination are or are not different in bacteria and eukaryotes?
Mechanisms of termination ARE different in bacteria and eukaryotes.
Where, in bacteria, does the polymerase stop transcription?
end of the terminator
Describe how termination of transcription occurs in eukaryotes?
polymerase continues transcription after the pre-mRNA is split from the growing RNA chain; the polymerase eventually falls off the DNA
(Eukaryotic Cells)
Enzymes modify pre-mRNA before..
the genetic messages are sent to the cytoplasm
How do enzymes modify pre-mRNA before the genetic messages are sent to the cytoplasm?
1. Alteration of mRNA ends
2. Splitting of Genes and RNA Splicing
During the alteration of mRNA ends, each end of a pre-mRNA molecule is modified in what way?
the 5' end receives a modified nucleotide 5' cap
the 3' end gets a poly-A tail
5' Cap
The 5' end of a pre-mRNA molecule modified by the addition of a cap of guanine nucleotide.
poly-A tail
A string of 200 to 300 adenine base pairs at the end of an mRNA transcript
Most eukaryotic genes and their RNA transcripts have what...
long noncoding stretches of nucleotides that lie between coding regions
Noncoding regions are called intervening sequences, aka..
Introns
Synonym for introns
intervening sequences
Coding regions are called...
Exons
Why are coding regions called exons?
Because they are eventually expressed which makes amino acid sequences.
RNA Splicing
removes introns and joins exons, creating an mRNA molecule with a continuous coding sequence
Some genes can encode more than one kind of polypeptide, depending on what..
depending on which segments are treated as exons during RNA splicing
Some genes can encode more than one kind of polypeptide, depending on which segments are treated as exons during RNA splicing. Such variations are called..
alternative RNA splicing
Because of alternative splicing, the number of different proteins an organism can produce is ____ than its number of genes.
much greater
A cell translates an mRNA message into what?
a protein
A cell translates an mRNA message into protein with the help of...
transfer RNA (tRNA)
Molecules of tRNA are or are not identical?
Molecules of tRNA are NOT identical
Why aren't molecules of tRNA identical?
-Each carries a specific amino acid on one end
-Each has an anticodon on the other end
Anticodon base-pairs with..
a complementary codon on mRNA
Accurate translation requires two steps..
1. Correct match between a tRNA and an Amino Acid
2. Correct match between the tRNA anticodon and mRNA codon
What enzyme is associated with the correct match between a tRNA and an amino acid
aminoacyl-tRNA synthetase
Wobble
Flexible pairing at the third base of a codon
Wobble (flexible pairing at the third base of a codon) allows some tRNAs to..
bind to more than one codon
Ribosomes
faciliate specific coupling of tRNA anticodons with mRNA codons in protein synthesis
Two ribosomal subunits
Large & Small
The two ribosomal subunits (large and small) are made of...
proteins & ribosomal RNA (rRNA)
A ribosome has ___ binding sites for tRNA.
3
What are the 3 binding sites for tRNA?
1. P site
2. A site
3. E site
P site
holds the tRNA that carries the growing polypeptide chain
A site
hold the tRNA that carries the next amino acid to be added to the chain
E site
the exit site, where discharged tRNAs leave the ribosome
3 Stages of Translation in building a polypeptide?
1. initiation
2. elongation
3. termination
The initiation stage of translation in building a polypeptide brings together 3 things..
1. mRNA
2. tRNA with first amino acid
3. Two ribosomal subunits
What happens first during the initiation of translation of building a polypeptide?
A small ribosomal subunit binds with mRNA and a special initiator tRNA
After a small ribosomal subunit binds with mRNA and a special initiator tRNA, what happens?
Small subunit moves along the mRNA until it reaches the start codon
The start codon
AUG
Proteins called ______ _______ bring in the large subunit that completes the translation initiation complex.
Initiations factors
During the elongation of the polypeptide chain, amino acids are...
added one by one to the preceding amino acid
Each addition of an amino acid during the elongation of the polypeptide chain involves proteins called _____ ___ and occurs in three steps.
Elongation factors
Each addition of amino acids during the elongation stage of the polypeptide chain occurs in three steps:
1. Codon recognition
2. Peptide bond formation
3. Translocation
Termination of translation occurs when..
a stop codon in the mRNA reaches the A site of the ribosome.
The A site during termination of translation accepts a protein called..
a release factor
The release factor causes the addition of a _______ molecule instead of an amino acid.
water
The release factor's reaction during termination of translation releases the __________ and the translation assembly then...
polypeptide
translation assembly then falls apart
A number of ribosomes can translate a single mRNA simultaneously, forming a _________.
polyribosome aka polysome
Polyribosome aka
polysome
Polyribosomes enable a cell to..
make many copies of a polypeptide very quickly
Often translation is not sufficient enough to make a...
functional protein
________ ______ are modified after translation.
polypeptide chains
________ ________ are targeted to specific sites in the cell.
Completed Proteins
Changes in the genetic material of a cell or virus are what?
mutations
Point mutations
chemical changes in just one base pair of a gene
Point mutations are chemical changes in just ___ base pair of a gene.
One
The change of ______ nucleotide in a DNA template strand can lead to the production of an abnormal protein.
just one
The change of a single nucleotide in a DNA template strand can lead to the production of a(n)..
abnormal protein
Point mutations within a gene are divided into two general categories. What are they?
-Base-pair substitutions
-Base-pair insertions or deletions
Base-pair substitution
replaces one nucleotide and it's partner with another pair of nucleotides
Silent mutations
base-pair substitutions with no effect on genetic code because of redundancy
Silent mutations have no effect on the amino acid produced by a codon because of..
redundancy in the genetic code
Silent mutations have to do with what kind of point mutations?
Base-pair substitutions
Missense mutations
still code for an amino acid, but not necessarily the right amino acid.
Missense mutations have to do with what kind of point mutations?
base-pair substitutions
Nonsense mutations
changes an amino acid codon into a stop codon, nearly always leading to a nonfunctional protein
Nonsense mutations have to do with what kind of point mutations?
base-pair substitutions
Insertions and deletions are...
additions or losses of nucleotide pairs in a gene
Compare the effects of insertions/deletions to substitutions.
insertions/deletions have a disastrous effect on the resulting protein more often than substitutions do
Insertion or deletion of nucleotides may alter the reading frame, producing a..
frameshift mutation
Frameshift Mutation
mutation that shifts the "reading" frame of the genetic message by inserting or deleting a nucleotide
Physical or chemical agents that can cause mutations are called..
mutagens
Spontaneous mutations can occur during..
DNA replication, recombination, or repair
When comparing gene expression, bacteria and eukarya differ in their...
RNA polymerases,
termination of transcription,
& ribosomes
When comparing gene expression, archae tends to resemble ____ in RNA polymerases, termination of transcription, and ribosomes.
Eukarya
_______ can simultaneously transcribe and translate the same gene.
Bacteria
In ______, transcription and translation are separated by the nuclear envelope.
Eukarya
In _______, transcription and translation are likely coupled.
Archaea
In a nucleotide, the nitrogenous base is attached to the sugar's _____ carbon and the phosphate group is attached to the sugar's _____ carbon.
1' ; 5'
Nucleic acids are assembled in the _____ direction.
5' --> 3'
Who demonstrated that DNA is the genetic material of the T2 phage?
Hershey & Chase
The enzyme that can replicate DNA is called..
DNA polymerase
The first step in the replication of DNA is catalyzed by _____.
Helicase
The action of helicase creates _____ & _______.
Replication forks & replication bubbles
Why is the new DNA strand complementary to the 3' to 5' strands assembled in short segments?
DNA polymerase can assemble DNA only in the 5' to 3' direction
The synthesis of a new strand begins with the synthesis of a(n) _____.
RNA primer complementary to a preexisting DNA strand
Short segments of newly synthesized DNA are joined into a continuous strand by _____.
Ligase
What catalyzes DNA synthesis?
DNA polymerase
______ are short sequences that allow the initiation of DNA synthesis.
Primers
Which part of a deoxynucleoside triphosphate (dNTP) molecule provides the energy for DNA synthesis?
Phosphate Groups
What enzyme creates a primer for DNA polymerase?
primase
Which of the following statements about Okazaki fragments in E. coli is true?
they are formed on the lagging strand of DNA
Which of the following enzymes is important for relieving the tension in a helix as it unwinds during DNA synthesis?
Topoisomerase
True or false? Single-stranded DNA molecules are said to be antiparallel when they are lined up next to each other but oriented in opposite directions.
True
Where would RNA polymerase attach?
to DNA
What name is given to the process in which a strand of DNA is used as a template for the manufacture of a strand of pre-mRNA?
Transcription
What name is given to the process in which the information encoded in a strand of mRNA is used to construct a protein?
Translation
What name is given to the process in which pre-mRNA is edited into mRNA?
RNA processing
Polypeptides are assembled from _____.
Amino Acids
RNA processing converts the RNA transcript into _____.
mRNA
What is the process called that converts the genetic information stored in DNA to an RNA copy?
Transcription
DNA does not store the information to synthesize which of the following?
Organelles
Transcription begins at a promoter. What is a promoter?
A nontranscribed sequence on the DNA
Which of the following statements best describes the promoter of a protein-coding gene?
promoter is a nontranscribed region of a gene
What determines which base is to be added to an RNA strand during transcription?
Base pairing between the DNA template strand and the RNA nucleotides
Which of the following terms best describes the relationship between the newly synthesized RNA molecule and the DNA template strand?
complementary
What happens to RNA polymerase II after it has completed transcription of a gene?
It is free to bind to another promoter and begin transcription.
The direction of synthesis of an RNA transcript is _____.
5' -> 3'
During RNA processing a(n) _____ is added to the 5' end of the RNA.
Modified guanine nucleotide
During RNA processing a(n) _____ is added to the 3' end of the RNA.
a long string of adenine nucleotides
Spliceosomes are composed of _____.
snRNPs and other proteins
The RNA segments joined to one another by spliceosomes are _____.
exons
Translation occurs in the _____.
Ribosomes within cytoplasm
Where does translation take place?
Ribosome
Which nucleic acid is translated to make a protein?
mRNA
Which of the following processes is an example of a post-translational modification?
Phosphorylation
Which of the following steps occurs last in the initiation phase of translation?
The large ribosomal subunit joins the complex.
At which site do new aminoacyl tRNAs enter the ribosome during elongation?
A-site
What is meant by translocation?
The ribosome slides one codon down the mRNA.
True or false. A tRNA with an anticodon complementary to the stop codon catalyzes the reaction by which translation is terminated.
False
What enzyme catalyzes the attachment of an amino acid to tRNA?
aminoacyl-tRNA synthetase
The initiator tRNA attaches at the ribosome's _____ site.
P
True or false? A codon is a group of three bases that can specify more than one amino acid.
False
Which mutation(s) would not change the remainder of the reading frame of a gene sequence that follows the mutation(s)?
One addition and one deletion mutation.
If a mutated DNA sequence produces a protein that differs in one central amino acid from the normal protein, which of the following kinds of mutations could have occurred?
An addition mutation and a deletion mutation.
Wobble
violation of the base-pairing rules in that the third nucleotide (5' end) of a tRNA anticodon can form hydrogen bonds with more than one kind of base in the third position (3' end) of a codon
ribosomal subunits
Large and small; in eukaryotes they are made in the nucleolus
p site
one of a ribosome's three binding sites for tRNA during translation. It holds the tRNA carrying the growing polypeptide chain.
a site
holds the tRNA carrying the next amino acid to be added to the chain
start codon
Codon (AUG) that signals to ribosomes to begin translation; codes for the first amino acid in a protein
stop codon
A group of nucleotides that does not specify a particular amino acid, but instead serves to notify the ribosome that the protein being translated is complete. The stop codons are UAA, UGA, and UAG. They are also known as nonsense codons.
Silent mutations
substitute one base pair for another, result is the same amino acid and has no phenotypic effect
Missense mutations
The most common type of mutation, a base-pair substitution in which the new codon makes sense in that it still codes for an amino acid, just not the same one.
post-translational modification
process in which polypeptides are chemically modified after being created
Where does replication, transcription, and translation occur?
replication-cell's nucleus
transcription-cytoplasm of the cell
translation-ribosomes attach to the mRNA and translate it into a polypeptide
Energy enters ecosystem as ____.
light
Cellular Respiration Formula
C6H12O6 + 6O2 --> 6CO₂ + 6H₂O + energy
The ATP made during glycolysis is generated by ________ ?
substrate-level phosphorylation
For each molecule of glucose that is metabolized by glycolysis and the citric acid cycle, what is the total number of NADH + FADH2 molecules produced?
12
During aerobic respiration, electrons travel downhill in which sequence?
food -> NADH -> Electron transport chain -> oxygen
In chemiosmotic phosphorylation, what is the most direct source of energy that is used to convert ADP + Pi to ATP?
Energy released from the movement of protons through ATP synthase
If citric acid has 6 carbon atoms, how many carbons does succinic acid have?
4
The oxygen consumed during cellular respiration is involved directly in which process or event?
accepting electrons at the end of the electron transport chain
How do the final electron acceptors differ between aerobic respiration, anaerobic respiration & fermentation?
Aerobic Respiration: oxygen is final electron acceptor
Anaerobic Respiration: inorganic or organic electron acceptors (usually an inorganic substance such as nitrate or sulfate)
Fermentation does not use electron transport chain.
Photosynthesis formula
6 CO2 + 12 H2O + Light energy ==> C6H12O6 + 6 O2 + 6 H2O
Do photosynthesizing plants have mitochondria?
Yes, to supply the plants with the ATP needed to power various cell activites
Random Fertilization
adds to genetic variation because any sperm can fuse with any ovum (unfertilized egg)
fusion of 2 gametes produces a zygote with any of about 70 trillion diploid combinations
each zygote has unique genetic identity
What is the role of NADP+ in photosynthesis?
It is reduced to NADPH and then carries electrons to the Calvin cycle.
Rubisco
The enzyme that catalyzes the first step of the Calvin cycle (the addition of CO2 to RuBP).
RuBP
ribulose biphosphate; a five-carbon carbohydrate that combines with CO2 to form two molecules of PGA in the first step of the Calvin Cylce
How many turns of the calvin cycle is needed to make one glucose molecule?
6
What are products of the light reactions of photosynthesis that are used in the Calvin cycle?
ATP and NADPH
When oxygen is released as a waste product of photosynthesis, it is a result of ____.
Splitting water molecules
What is the primary function of the Calvin cycle?
make simple sugars from carbon dioxide
In mitosis, if a parent cell has 16 chromosomes, each daughter cell will have how many chromosomes?
16
Cells with two of each kind of chromosome are described by the term ______.
diploid
The chromosomes and genes are actually replicated during _______.
'S' Phase of Interphase
If the liver cells of an animal have 24 chromosomes, the sperm cells would have how many chromosomes?
12
What are the three stages in interphase?
G1 phase ("first gap")
S phase ("synthesis")
G2 phase ("second gap")
The phases of mitosis in the correct order are
Prophase, metaphase, anaphase, telophase
Which phase of the cell cycle is incorrectly described?
a. G1: a time of slow cell growth
b. S: DNA is replicated
c. G2: A cell prepares for division
d. M: nuclear and cytoplasmic division
a. G1: a time of slow cell growth
Which of the following is true of a species with a chromosome number of 2n = 16?
a. Each cell has 8 homologous pairs.
b. The species has 16 pairs of chromosomes per cell.
c. The species is diploid with 32 chromosomes per cell.
d. During the S phase of the cell cycle there will be 32 separate chromosomes.
e. A gamete from this species has 4 chromosomes.
a. Each cell has 8 homologous pairs.
Which phase of the cell cycle is incorrectly described?
a. G1: organelles are replicated
b. S: DNA is replicated
c. G2: replicated DNA separates
d. M: nuclear and cytoplasmic division occurs
c. G2: replicated DNA separates
When is DNA replicated?
S phase (interphase)
When do homologous chromosomes separate?
Anaphase I
When are tetrads formed?
Prophase I
When do sister chromatids separate?
Anaphase II (as well as in mitosis)
Where does interphase occurs?
Before Meiosis
Meiosis versus Mitosis
-Mitosis conserves the number of chromosome sets, producing cells that are genetically identical to the parent cell.
-Meiosis reduces the number of chromosomes sets from two (diploid) to one (haploid), producing cells that differ genetically from each other and from the parent cell
-The mechanism for separating sister chromatids is virtually identical in meiosis II and mitosis.,
____
-Mitosis results in a diploid daughter cell (46 paired chromosomes). --Meiosis gives a haploid gamete of 23 unpaired chromosomes.
-Mitosis takes place in somatic (Tissue) cells.
-Meiosis takes place in gamete production and maturation
-Mitosis is a single step process (although it has many phases).
-Meiosis can be considered as two cell divisions Meiosis I and Meiosis II.
When does DNA replication occur in Mitosis?
When does DNA replication occur in Meiosis?
Mitosis - occurs during interphase before mitosis begins
Meiosis - occurs during interphase before meiosis I begins
Number of divisions in Mitosis
One, including prophase, metaphase, anaphase, and telophase
Number of divisions in Meiosis
Two, each including prophase, metaphase, anaphase, and telophase
When does synapsis of homologous chromosomes occur in mitosis?
it does not occur.
When does synapsis of homologous chromosomes occur in meiosis?
Occurs during Prophase I along with crossing over between nonsister chromatids
Number of daughter cells in Mitosis?
2 (each diploid (2n) and genetically identical to the parent cell)
Number of daughter cells in Meiosis?
4 (each haploid (n) containing half as many chromosomes as the parent cell; genetically different from the parent cell and from each other)
Mitosis' role in the animal body
enables multicellular adult to arise from zygote;
produces cells for growth, repair, and in some species, asexual reproduction
Meiosis' role in the animal body
produces gametes;
reduces number of chromosomes by half;
introduces genetic variability among gametes
How do genetic variations occur?
mutations, alleles, and reshuffling alleles
3 mechanisms that contribute to genetic variation:
1. Independent assortment of chromosomes
2. Crossing over
3. Random fertilization
Independent Assortment of Chromosomes
each pair of chromosomes sorts maternal and paternal homologues into daughter cells independently of the other pairs, homologous pairs of chromosomes orient randomly at metaphase 1 of meiosis, each pair of chromosomes sort maternal and paternal homologues into daughter cells independently of other pairs
Crossing Over
Produces recombinant chromosomes;
begins very early in prophase I, as homologous chromosomes pair up gene by gene
homologous portions of two nonsister chromatids trade places
contributes to genetic variation by combining DNA from two parents into a single chromosome
Energy leaves the ecosystem as ___.
Heat
Photosynthesis generates ___ and ___.
O2 and organic molecules (which are used in cellular respiration)
Cells use chemical energy stored in organic molecules to regenerate ___, which powers work.
ATP
Metabolism
sum of all chemical reactions within a living organism
2 Categories of Metabolism:
1. Catabolic pathways
2. Anabolic pathways
Catabolic Pathways
-Break down complex organic compounds into simple ones
-Releases energy!
Anabolic Pathways
-Combine simple organic substances into more complex organic molecules
-Uses energy!
3 Catabolic Pathways
1. Carbohydrate Catabolism
2. Lipid Catabolism
3. Protein Catabolism
Carbohydrate (Glucose) Catabolism
C6H12O6+6CO2==>6CO2+6H2O+Energy (ATP + Heat)
3 Energy Production Concepts
1. Oxidation-Reduction
2. Electron Carriers
3. ATP Generation
Oxidation
loss of electrons
Reduction
gain of electrons
Oxidation-Reduction
Redox Reactions & Dehydrogenation;
Glucose is oxidized, Oxygen is reduced
(formula is that of the carbohydrate catabolism)
Redox Reactions
coupling of oxidation and reduction;
releases kinetic energy which makes ATP
Dehydrogenation
loss of hydrogen ions at the same time as removal of electrons in cellular oxidations
Electron Carriers
Accept and release electrons and hydrogen ions;
most are co-enzymes
(Electron Carriers)
Some are free in ______; others are attached to ____ _____ of ________.
some are free in CYTOPLASM; others are attached to INNER MEMBRANE of MITOCHONDRIA
(Electron Carriers)
Each NADH represents ____ ____ that will eventually be used to make ____.
each NADH represents STORED ENERGY that will eventually be used to make ATP.
Attached electron carriers are located in the ______ ______ ______ in the ________.
Electron Transport Chain (ETC);
Mitochondria
(Electron Carriers)
Step 1: The electron transport chain (ETC) passes ________ in a series of steps called _______ ______.
The electron transport chain (ETC) passes ELECTRONS in a series of steps called REDOX REACTIONS
(Electron Carriers)
Step 2: Energy is _____ during the step-wise process (redox reactions) due to the ETC.
Released
(Electron Carriers)
Step 3: The energy released from redox reactions in the ETC is used to make ____.
ATP
(Electron Carriers)
Step 4: Electrons are finally ______ by ______ (final electron acceptor).
Electrons are finally ACCEPTED by OXYGEN
(Generation of ATP)
Energy released during oxidation is _____ within the cell by formation of _____.
Energy released during oxidation is TRAPPED within the cell by formation of ATP.
(Generation of ATP)
ATP is formed by ___________.
Phosphorylation
3 Mechanisms for phosphorylation:
1. Substrate-level Phosphorylation
2. Oxidation Phosphorylation
3. Photophosphorylation
Substrate-Level Phosphorylation
High energy phosphate group from a substrate is added directly to ADP;
Substrate is usually an organic molecule that is an intermediate in a catabolic pathway
Oxidative Phosphorylation
ATP is synthesized during the series of redox reactions that take place in the Electron Transport Chain
Photophosphorylation
occurs during photosynthesis, The process of generating ATP from ADP and phosphate by means of a proton-motive force generated by the thylakoid membrane of the chloroplast during the light reactions of photosynthesis.
2 Types of Carbohydrate Catabolism
Cellular Respiration & Fermentation
Cellular respiration uses ______ whereas fermentation does NOT.
Electron Transport Chain
2 Types of Cellular Respiration:
Aerobic Respiration & Anaerobic Respiration
Cellular Respiration is often used to refer to _______ _________.
aerobic respiration
4 Key Metabolic Stages of Aerobic Respiration:
1. Glycolysis
2. Transition Stage
3. Krebs Cycle (Citric Acid Cycle)
4. Oxidative Phosphorylation
Glycolysis
splitting of sugar; oxidation of glucose to 2 molecules of pyruvic acid
Glycolysis occurs in the..
Cytoplasm
_______ is the most common pathway for oxidation of glucose
Glycolysis
(Glycolysis)
Yield from one glucose:
-2 pyruvates
-2 ATPs (net) via substrate-level phosphorylation
-2 NADH
Transition Stage: Formation of ______-___
Acetyl-CoA
(Transition Stage)
If ______ is present, pyruvate enters the _______.
if OXYGEN is present, pyruvate enters the MITOCHONDRIA
(Transition Stage)
Once pyruvate enters the mitochondria (and oxygen is present), it is converted to ______ which occurs in the _________ ________.
Acetyl CoA; Mitochondrial matrix
(Transition Stage)
Formation of Acetyl-CoA:
Yield from 2 pyruvates:
-2 Acetyl-CoA
-2 CO2
-2 NADH
Krebs Cycle AKA
Citric Acid Cycle
Citric Acid Cycle has ___ steps.
8
Each step of the Citric Acid Cycle is ______ by a specific _____
catalyzed; enzyme
From Transition Stage, Acetyl-CoA enters the Citric Acid Cycle by combining with ______ ______.
Oxaloacetic Acid
The seven steps after Acetyl-CoA combines with oxaloacetic acid in the Citric Acid Cycle include _____ and _____ of ______.
The seven steps after Acetyl-CoA combines with oxaloacetic acid in the Citric Acid Cycle include OXIDATION and BREAKDOWN of SUBSTRATES.
In the last step of the Citric Acid Cycle _______ _____ is regenerated thus making it a cycle.
Oxaloacetic acid
(Citric Acid Cycle)
Yield from 2 Acetyl CoA molecules:
-2 ATP
-2 FADH2
-6 NADH
-4 CO2
How many turns of the Citric Acid Cycle is needed for each glucose molecule?
2
(Oxidative Phosphorylation)
Reduced co-enzymes (NADH,FADH2) carry _____ _____.
Potential Energy
(Oxidative Phosphorylation)
High energy electrons are transferred from co-enzymes to the _____ .
ETC (Electron Transport Chain)
(Oxidative Phosphorylation)
In the ETC - step wise release of ____ occurs as _________ are transferred from one electron carrier to another.
energy ; electrons
Chemiosmosis
the use of energy in a H+ gradient to drive cellular work; exergonic flow of H+ through ATP synthase drives synthesis of ATP
(Oxidative Phosphorylation:
Chemiosmosis)
In the ETC, each electron transfer is a ________ reaction and is associated with ________ _______.
In the ETC, each electron transfer is a REDOX reaction and is associated with ENERGY RELEASE.
(Oxidative Phosphorylation:
Chemiosmosis)
Energy release is ______ to pumping of hydrogen ion into the __________ space of the _______.
Energy release is COUPLED to pumping of hydrogen ion into the INTERMEMBRANE space of the MITOCHONDRIA.
Proton Motive Force
H+ increase in concentration in the intermembrane space
ATP Synthase
Protein complex in which hydrogen ions move back into the matrix through
ATP synthase phosphorylates ___ + ___ to _____.
ATP synthase phosphorylates ADP + Pi to ATP
The ______ flow of H+ through ATP synthase drives synthesis of ATP.
exergonic
(Oxidative Phosphorylation)
Yield in the ETC:
1 NADH -> 3 ATPs
1 FADH2 -> 2 ATPs
Reduced co-enzymes that enter ETC:
Glycolysis = __ NADH
Transition Stage = __ NADH
Citric Acid Cycle = __ NADH + __ FADH2
TOTAL ATP = ___ ATPs
Reduced co-enzymes that enter ETC:
Glycolysis = 2 NADH
Transition Stage = 2 NADH
Krebs Cycle = 6 NADH + 2 FADH2
Total = 10 NADH + 2 FADH2
Total = 30 ATPs + 4 ATPs = 34 ATPs
Total Theoretical ATP yield from 1 glucose molecule during aerobic respiration:
Glycolysis: __ ATPs
Transition Stage: __ ATPs
Citric Acid Cycle: __ ATPs
ETC: __ ATPs
TOTAL: __ ATPs from one glucose molecule
NOTE: Some cells yield only __ ATPs
Glycolysis: 2 ATPs (substrate level phosphorylation)
Transition stage: 0 ATP
Krebs Cycle: 2 ATPs (substrate level phosphorylation)
ETC: 34 ATPs (oxidative phosphorylation)

Total: 38 ATPs from one glucose molecule
Note: Some cells yield only 36 ATPs
When does anaerobic respiration occur?
Absense of oxygen
In anaerobic respiration, glucose first undergoes _______.
Glycolysis
Glycolysis occurs with or without _____.
oxygen
After undergoing glycolysis in anaerobic respiration, it uses an _____.
Electron Transport Chain
Final electron acceptor is ___ oxygen in anaerobic respiration; the final electron acceptor is usually an __________ __________.
NOT; inorganic substance
Anaerobic Respiration occurs in ______.
Bacteria (prokaryotes)
Fermentation occurs in the absense of __________.
Oxygen
During fermentation, glucose first undergoes _________.
Glycolysis
During fermentation, _______ is converted to a variety of end products.
pyruvate
Fermentation regenerates _______ for use in glycolysis.
NAD+
Fermentation does or does not use an electron transport chain?
DOES NOT use an electron transport chain
Two Common Types of Fermentation:
Alcohol fermentation;
Lactic Acid Fermentation
In alcohol fermentation, pyruvate is converted to _________ in ____ steps, the first step releasing _______.
Ethanol; 2 steps; CO2
Alcohol fermentation by _____ is used in brewing, winemaking, and baking.
yeast
In Lactic Acid Fermentation pyruvate is reduced to ____, forming ______ as an end product, with no release of CO2.
NADH, Lactate
Lactic Acid Fermentation by ____ and ______ is used to make cheese and yogurt.
fungi and bacteria
_______ _____ cells use lactic acid fermentation to generate ATP when O2 is scarce.
Human Muscle Cells
Final Electron Acceptors for Aerobic Respiration, Anaerobic Respiration, and Fermentation.
Aerobic - oxygen
Anaerobic - inorganic molecule
Fermentation - organic molecule
ATP Production in Aerobic Respiration, Anaerobic Respiration, and Fermentation.
Aerobic - 38 ATPs
Anaerobic - varies
Fermentation - 2 ATPs
Protein Catabolism
proteins break down in to amino acids and undergo a variety of conversions; products can enter glycolysis or kreb's cycle
Enzymes for Protein Catabolism
Proteases
Lipid Catabolism
Lipids are hydrolyzed into glycerol and fatty acids
In lipid catabolism, glycerol enters _____.
glycolysis
In lipid catabolism, fatty acids yield ______ ____.
Acetyl CoA
Anabolic Pathways
Body uses small molecules to build other substances
In anabolic pathways where do the small molecules come from?
Food, glycolysis, or citric acid cycle
Photosynthesis
process that converts solar energy into chemical energy
Directly or indirectly, photosynthesis nourishes almost _____.
The entire world.
Autotrophs
make their own food
Autotrophs are _______ of the biosphere.
producers
Almost all plants are __________.
photoautotrophs
Photoautotrophs
use energy of sunlight to make organic molecules from H2O and CO2
Photosynthesis occurs in...
plants, algae, certain other protists, and some prokaryotes
Heterotrophs
obtain their organic material from other organisms
Heterotrophs are the _______ of the biosphere.
consumers
Almost all heterotrophs, including humans depend on _________ for food and O2.
photoautotrophs
Where does the site of photosynthesis take place?
Chloroplasts
Structural organization of the chloroplasts allow for the chemical reactions of __________.
photosynthesis
Chloroplasts are structurally similar to ___________ ________.
Photosynthetic Bacteria (probably where they came from to begin with)
________ are the major locations of photosynthesis.
Leaves
Green color in plants is from ________, the green pigment within __________.
chlorophyll; chloroplasts
_______ ________ absorbed by ___________ drives the synthesis of organic molecules in the chloroplast.
Light energy; chlorophyll
CO2 enters and O2 exits the leaf through microscopic pores called ________.
Stomata
Chloroplasts are found mainly in cells of the _________.
Mesophyll
Mesophyll
interior tissue of the leaf
A typical mesophyll cell has how many chloroplasts?
30-40
Chloroplast structure includes ___ membranes.
3
Three membranes of chloroplast's structure are:
1. Smooth outer membrane
2. Smooth inner membrane
3. Complex third membrane
Complex third membrane of chloroplast consists of what?
Thylakoids which form a granum and stroma
Thylakoid
membranous sacs that are connected within complex third membrane of chloroplasts
Granum
stack of thylakoids (grana when plural) within complex third membrane of chlorolasts
Stroma
internal fluid of complex third membrane of chloroplasts
What are the 2 stages of photosynthesis?
Light Dependent Reactions & Light-Independent Reactions (Calvin Cycle)
In Light Dependent Reactions, ______ ______ (which involves chlorophyll) converts in to ________ _________ _________.
Light Energy; High Energy Compounds
In light dependent reactions, _______ is released.
Oxygen
In light-independent reactions (aka The Calvin Cycle) ______ & ________ are used to make __________ from _____.
ATP & NADPH are used to make CARBOHYDRATES from CO2
Chloroplasts are ____-powered ______ factories.
Chloroplasts are SOLAR-powered CHEMICAL factories
Light is a form of ___________ energy.
electromagnetic
Light is a part of the ___________ spectrum
electromagnetic
The shorter the wavelength the _____ the energy.
higher
_____ _____ have the shortest wavelength and the highest energy.
Gamma Rays
(X-Rays & UV are same pattern)
_______ ______ have the longest wavelength with the lowest energy.
Radio Waves
(infrared & microwaves are same pattern)
Purple represents _____ wavelengths with ________ energy.
Shorter, higher
Red represents ______ wavelengths with ______ energy.
longer, lower
3 Characteristics of Light:
1. Travels in waves
2. Behaves as a particle
3. Photons can interact with atoms
Wavelength
the distance between crests of waves
Photons
packets of energy
Shorter the wavelength, the ______ energy per photon.
more
When photons interact with atoms, they can _____ electrons to a _______ energy level.
Excite; higher
Two things can happen when photons interact with atoms. They can either _____ to ground state which can create fluorescence, or excited electrons _____ atom and go to an ______ ______ _______.
Two things can happen when photons interact with atoms. They can either RETURN to ground state which can create fluorescence, or excited electrons LEAVE atom and go to an ELECTRON ACCEPTOR MOLECULE.
Fluorescence
emission of light
Pigments
substances that absorb visible light
Different pigments absorb ______ wavelengths.
different
Wavelengths that are not absorbed are _______ or _______.
Reflected or Transmitted
Chlorophyll absorbs light in the ____ and ____ regions.
blue and red
Leaves appear green because chlorophyll ______ and _________ green light.
reflects and transmits
Main photosynthetic pigment
Chlorophyll a
Chlorophyll a (color)
green
Chlorophyll b
yellow-green
Carotenoids (pigment color)
yellow & orange
Which process produces oxygen, cellular respiration or photosynthesis?
photosynthesis
What sequences correctly represents the flow of electrons during photosynthesis?
H2O--> NADPH-->Calvin cycle
Does the release of oxygen occur in the Calvin Cycle?
NO!
In the electromagnetic spectrum, the type of radiation that we call visible light occurs between _____.
ultraviolet radiation and infrared radiation
Light energy during light-dependent reactions is used to do two things.
1. Make ATP
2. Reduce NADP+ to NAPH2
Light-Dependent Reactions involves ________ __ and _________ ______.
Chlorophyll A and Accessory Pigments
Photosystems
Pigments that are organized into units
Where are photosystems located?
Thylakoid membranes
A photosystem consists of....
A reaction-center complex surrounded by light-harvesting complexes
Reaction-center complex
a type of protein complex
Light-Harvesting complexes
pigment molecules that are bound to proteins
What do light-harvesting complexes do in photosystems I & II?
funnel the energy of photons to the reaction center
In photosystems I & II, a primary electron acceptor does what in the reaction center?
It accepts an excited electron from chlorophyll a
What is the first step of the light reactions in photosystems?
Solar-powered transfer of an electron from a 'chlorophyll a' molecule to the primary electron acceptor
Two types of photosystems in the thylakoid membrane:
1. Photosystem II (PS II)
2. Photosystem I (PS I)
Photosystem __ functions first.
II
Photosystem II is best at absorbing a wavelength of ___ nm
680 nm
The reaction-center chlorophyll a of PS II is called ___.
P680
Photosystem I is best at absorbing a wavelength of ____ nm.
700 nm
The reaction-center chlorophyll a of PS I is called _____
P700
During the light-dependent reactions, there are two possible routes for electron flow:
1. Linear electron flow
2. Cyclic electron flow
Linear Electron Flow
primary pathway which involves both photosystems I and II.
Linear electron flow produces _____ and ______ using ______ ______.
ATP & NADPH using light energy.
In linear electron flow, a pigment and its energy is passed among _____ ______ until it excites _____.
Pigment molecules; P680
In linear electron flow, an excited electron from P680 is ________ to the ______ _______ ______.
transferred; primary electron acceptor
P680+ is a P680 that is..
missing an electron
P680+ is a very strong ________ agent.
oxidizing
In linear electron flow, H2O is split by _________, and the ______ are transferred from the hydrogen atoms to P680+ thus reducing it to ______.
enzymes, electrons, P680
In linear electron flow after P680+ is reduced to P680, ____ is released as a by-product of the reaction.
O2
In linear electron flow, each electron "falls" down an _________ ________ _____ from the primary electron acceptor of PS II to PS I.
electron transport chain
In linear electron flow, energy released by the fall drives the creation of a _____ ______ across the _______ membrane.
proton gradient; thylakoid
Diffusion of H+ (protons) across the membrane after creation of the proton gradient across the thylakoid membrane drives _____ ______.
ATP synthesis
In linear electron flow, In PS I (like PS II), transferred light energy excites _____, which loses an ______ to an _______ ______.
P700, Electron, Electron Acceptor
In linear electron flow, P700+ (P700 that is missing an electron) _________ an electron passed down from PS ___ through the _______ ________ _______.
accepts, PS II, Electron Transport Chain
In linear electron flow, each electron "falls" down an electron transport chain from the primary electron acceptor of _____ to the protein, ___________.
PS I, Ferredoxin (Fd)
In linear electron flow, after the electrons have "fallen" down to the protein, ferredoxin, the electrons are then transferred to _______ and _______ it to _________,
NADP+ and reduce it to NADPH
In linear electron flow, after electrons are transferred to NADP+ and have reduced it to NADPH, the electrons are available for the reactions of the ________ ________.
Calvin Cycle
Cyclic Electron Flow
generates surplus ATP, satisfying the higher demand in the Calvin Cycle.
Cyclic electrong flow uses only __________ and produces ____, but not _______.
Uses only PS I and produces ATP, but nottttt NADPH
In cyclic electron flow, in PS I, light energy excites ______ which causes the electron to be ___________ to the __________ ________.
Light energy excites P700, which causes the electron to be TRANSFERRED to the ELECTRON ACCEPTOR.
In cyclic electron flow, once electrons are transferred to electron acceptor, photoexcited electrons are _________ to ___________ which is _______ to ________ ________ , and then back to ________.
In cyclic electron flow, once electrong are transferred to electron acceptor, photoexcited electrons are TRANSFERRED to FERREDOXIN (Fd) which is TRANSFERRED to CYTOCHROME COMPLEX and back to P700.
In cyclic electron flow, ATP is synthesized by ______.
Chemiosmosis
In cyclic electron flow, NADPH is _____ produced.
NOT!!
In cyclic electron flow, oxygen is _______ generated.
NOT
_________ _________ _________ occurs when there are low concentrations of NADP+.
Cyclic Electron Flow
Chemiosmotic generation of ATP occurs in the ________ _________.
Thylakoid membrane
In chemiosmotic generation of ATP, electrons are transferred through chain of _________ _________ where energy is ___________. From there, energy pumps ______ (H+) from _______ to __________ space. This allows H+ concentration to __________. Then, H+ diffuses by _________ back to _______ via ATP synthase enzyme. Then, energy is released as ___ flows through. The energy is used for ______ + ___ which creates ATP.
In chemiosmotic generation of ATP, electrons are transferred through chain of ELECTRON-ACCEPTORS where energy is GENERATED. From there, energy pumps PROTONS (H+) from STROMA to THYLAKOID space. This allows H+ concentration to INCREASE. Then, H+ diffuses by DIFFUSION back to STROMA via ATP synthase enzyme. Then, energy is released as H+ flows through. The energy is used for ADP + Pi which creates ATP.
With chemiosmotic generation of ATP, ATP is generated by _________.
Photophosphorylation
Light-Independent Reactions are also called the ______ _______ or _______ ______.
Calvin cycle, dark reactions
The calvin cycle, builds _______ from smaller molecules by using ____ and the reducing power of electrons carried by ______.
Sugar
ATP
NADPH
Carbon enters the calvin cycle as CO2 and leaves as a _________ named __________.
Sugar ; glyceraldehyde-3-phosphate (G3P)
For net synthesis of 1 G3P, the calvin cycle must turn ___ times, fixing ___ molecules of CO2.
3 ; 3
Where does the calvin cycle occur?
Stroma
3 Phases of the Calvin Cycle:
1 Carbon fixation
2 Reduction
3 Regeneration of the CO2 acceptor (RuBP)
Carbon fixation is catalyzed by what enzyme?
Rubisco
In Calvin Cycle, _______ _______ combines with ________ which generates ___ carbon molecule.
Carbon dioxide; RuBP; 6
6-C molecules in Calvin Cycle instantly _____ into _____ molecules of _________.
SPLIT into TWO molecules of PHOSPHOGLYCERATE (3-C)
Phosphoglycerate is converted to ____ in the calvin cycle; uses ____ & _____ from ____________ reactions.
G3P ; ATP & NADHP ; light-dependent
__ turns of the Calving cycle creates ___ molecules of G3P.
6 ; 12
Calvin Cycle: 2 G3P is used to make ___ glucose molecule(s)
1
Calvin Cycle: ___ G3P are modified which generates __ molecules RuBP
10 ; 6
When comparing chemiosmosis in chloroplasts and mitochondria, ____ generate ATP by chemiosmosis, but use _________ sources of energy.
both ; different
When comparing chemiosmosis in chloroplasts and mitochondria, mitochondria transfers ____ energy from ____ to ATP. Chloroplasts transforms ___ energy into the ______ energy of ATP.
chemical ; food ; light ; chemical
When comparing chemiosmosis in chloroplasts and mitochondria- in mitochondria, protons are pumped to the ____________ space and drive ATP synthesis as they ______ back into the ________ _______.
protons are pumped to the INTERMEMBRANE space and drive ATP synthesis as they DIFFUSE into the MITOCHONDRIAL MATRIX.
When comparing chemiosmosis in chloroplasts and mitochondria - in chloroplasts, protons are pumped into the _______ space and drive ATP synthesis as they _______ back into the _____.
Thylakoid space, diffuse, stroma
Photosynthesis consists of the ______ _______ (the "photo" part) and the _______ _________ (the "synthesis" part).
Light Reactions
Calvin Cycle
Summary of light reactions:
They are in the __________.
1. Split ________
2. Release ____
3. Reduce ______ to ________
4. Generate ATP from ADP by ___________.
They are in the thylakoids
1. split H2O
2. release O2
3. Reduce NADP+ to NADPH
4. Generate ATP from ADP by PHOTOPHOSPHORYLATION
The Calvin Cycle (in the ______) forms _________ from CO2, using _______ & _______.
Stroma
Sugar
ATP & NADPH
Calvin Cycle begins with __________ ____________, incorporating CO2 into __________ molecules.
Carbon fixation, organic
In Photorespiration, rubisco adds _____ instead of ________ in the calvin cycle.
O2, CO2
On hot, dry days, plants close _______, which conserves ____ but also limits _________.
stomata, H2O, photosynthesis
The closing of stomata reduces access to ___ and causes _____ to build up.
CO2, O2
Photorespiration is a ______ process.
wasteful
In most plants, CO2 fixation via rubisco creates a __________ compound.
3-Carbon
Photorespiration consumes _____ and ______ fuel and releases ______ without producing ___ or ______.
O2, organic, CO2, ATP, sugar
Photorespiration may be an evolutionary relic because rubisco first evolves at a time when the atmosphere had far less O2 and more CO2.
True
Photorespiration can drain as much as ___% of the carbon fixed by the calvin cycle
50
Cell Cycle has 3 Main Parts:
1. Interphase
2. Mitosis
3. Cytokinesis
Cell division allows a continuation of life. T/F
True
In unicellular organisms, division of one cell reproduces...
the entire organism
Multicellular organisms depend on cell division for:
Reproduction,
Growth and Development
Tissue Repair
2 types of Cell Division:
Mitosis & Meiosis
Mitosis
Most cell division results in daughter cells with identical genetic info. (DNA)
Somatic Cell
Daughter cell; 2 sets of chromosomes; non-reproductive cell
Meiosis
special type of division that produces non-identical daughter cells
Gamete
reproductive cells; have half as many chromosomes as somatic
Genome
all DNA in a cell
Genome can consist of a _______ DNA molecule or _____ DNA molecules.
Single ; Several
Prokaryotic Cells
consists of a single DNA molecule
Eukaryotic cell
several DNA molecules
DNA molecules in a cell are packaged into:
chromosomes
In eukaryotes, chromosomes are paired. These chromosomes are called.
Homologous chromosomes
Are homologous chromosomes identical?
They are similar but NOT identical
Autosomes
all chromosomes minus sex chromosomes
Females have ___ pairs of homologous chromosomes.
23
Males have _____ pairs of autosomes and one x and one y.
22
Chromosomes consist of ______, a complex of DNA and protein that condenses during cell division.
Chromatin
In preparataion for cell division, _____ is replicated and the chromosomes _____.
DNA ; chromosomes condense
Each duplicated chromosome has two ________ ________, which separate during cell division.
Sister chromatids
Centromere
narrow waist of the duplicated chromosome, where the two chromatids are most closely attached
Centromeres are required to separate duplicated chromosomes. T/F
True
The cell cycle consists of the M phase which is properly known as the _________ phase. ________ & ________ occur during this phase.
Mitotic phase;
Mitosis and cytokinesis
Interphase
Cell growth and copying of chromosomes in preparation for cell division
__________ takes about 90% of the cell cycle.
Interphase
Interphase has 3 subphases:
G1 phase (first gap)
S phase (synthesis)
G2 phase (second gap)
Mitosis has 5 phases:
1. Prophase
2. Prometaphase
3. Metaphase
4. Anaphase
5. Telophase
Cytokinesis is well underway by late __________
Telophase
One cell division takes about _____ hours
18-24
Mitosis and Cytokinesis take how long
less than 1 hour
Mitotic Spindle
Apparatus of microtubules that controls chromosome movement during mitosis
During prophase, assembly of _____ ________ begins in the centrosome.
Sprindle Microtubules
Centrosome
microtubules organizing center
The Centrosome ________, forming ______ centrosomes that migrate to ________ ends of the cell, as spindle microtubules grow out of them.
replicates, 2, opposite
Aster
radial array of short microtubules
An aster _________ from each centrosome.
extends
The spindle includes the... (3)
centrosomes, spindle microtubules, and the asters
During prometaphase, some spindle microtubules attach to the _______ of chromosomes and begin to _____ the chromosomes.
kinetochores ; move
Growth occurs in all 3 stages of interphase but chromosomes are replicated only during ___ phase.
S
By end of interphase...
Chromosomes are _______
Centrosome has _____
Nuclear membrane is _____
Nucleus has ______
Chromosomes are replicated (2 copies)
Centrosome has duplicated
Nuclear membrane still intact
Nucleus has nucleoli
When prophase begins, _______ begin to condense (tightly coiled)
Chromatin
In prophase, ______ disappear.
Nucleoli
In prophase, duplicated chromosomes appear as two ______ ______ ________ _____ ; still joined by ______.
identical sister chromatids ; centromere
In prophase, what begins to form?
Mitotic spindle
In prophase, centrosomes _______ _____ and begin to _______ to _______ ends of the cells.
move apart ; migrate ; opposite
Prometaphase:
Nuclear membrane begins to ____.
Break down
Prometaphase:
Chromosomes become more _____.
condensed
Prometaphase:
each sister chromatid now has a ______
kinetochore
Kinetochore
specialized protein structure in the centromere
Prometaphase:
Some microtubules attach to ___
kinetochore
Prometaphase:
non-kinetochore tubules interact with those from _________ poles of spindle.
opposite
Metaphase:
___________ stage of mitosis (terms of time)
Longest (20 minutes)
Metaphase:
Centrosomes are now at __________ poles.
opposite
Metaphase:
Chromosomes align at the center of cell called the ______
Metaphase plate
Metaphase:
Chromosomes centromeres lie on ______
metaphase plate
Metaphase:
For each chromsome, __________ of sister chromatid are attached to ________ __________ coming from opposite poles.
kinetochores; kinetochore tubules
Anaphase is the ______ of mitosis. (time)
Shortest (few minutes)
Anaphase:
Sister chromatid ______ from each other which becomes a full-fledged _______.
separate ; chromosome
Anaphase:
Kinetochore microtubules attached to centromere of each sister chromatid begin to ________ --> chromosomes move _______ first.
shorten ; centromere
Anaphase:
Non-kinetochore microtubules _________ cause the cell to ______.
lengthen ; elongate
At the end of anaphase, the ends of the cell have _____ and _______ collections of chromosomes.
complete & identical
Telophase:
__________ form around each collection of chromosomes.
nuclear envelopes
Telophase:
________ reappear in each nucleus.
Nucleoli
Telophase:
________ uncoil and become less condensed.
Chromosomes
Telophase:
what forms at opposite ends of the cell?
Genetically identical daughter nuclei
Telophase:
Overlaps with ________ which is when the contractile ring assembles.
cytokinesis
Cytokinesis:
in animals, cytokinesis occurs by a process known as ________, forming a _________.
cleavage ; cleavage furrow
Cytokinesis:
Contractile Ring, what is it made of? and where does it form?
made of microfilaments
forms on cytoplasmic side
Cytokinesis:
Microfilaments _______, then the cleavage furrow _______, then the cell gets _______ into 2 new daugher cells.
contract; deepens; pinched
Cytokinesis:
In plants, a _____ forms during this phase.
cell plate
_____ _____ gives rise to the plasma membranes and cell walls of the two daughter cells in plant cells.
Cell plate
Prokaryotes (bacteria & archaea) reproduce by a type of cell division called _____
Binary fission
Binary fission
chromosome replicates (beginning at the origin of replication), and the two daughter chromosomes actively move apart
A normal cell is converted to a cancerous cell by a process called ______
transformation
Cancer cells form,
tumors, masses of abnormal cells within otherwise normal tissue
Benign tumor
abnormal cells remaining at original site
Mignant tumor
invades surrounding tissues and can metastasize (export more cancerous cells to the body), where they may form secondary tumors
Genetics
scientific study of heredity and variation
Heredity
transmission of traits from one generation to the next
Variation
the differences in appearance offspring show from parents and siblings
Genes
units of heredity (made up of segments of DNA)
Each gene has a specific location called a _______ on a certain chromosome.
Locus
How many sets of chromosomes are inherited from each parent?
1
Karyotype
ordered display of the pairs of chromosomes from a cell
For humans, the diploid number is ____
46 (2n=46)
Fertilization
union of gametes
Zygote
fertilized egg
Zygote produces _____ cells by _____ and develops into an adult.
somatic ; mitosis
Meiosis:
2 cell divisions result in ____ daughter cells, rather than 2 from mitosis
4
Each daughter cell has only ___ as many chromosomes as the parent cell.
half
Meiosis I =
Meiosis II =
homologous chromosomes separate (meiosis i)
sister chromatids separate (meiosis ii)
Reductional division
2 haploid daughter cells with replicated chromosomes
Equational division
four haploid daughter cells with unreplicated chromosomes
Mitosis ______ the number of chromosome sets, producing cells that are ________ to the parent cell.
conserves ; genetically identical to the parent cell
Meiosis _____ the number of chromosome sets from ___ to ___, producing cells that _______.
reduces ; from 2 to 1 ; differ genetically from each other and from the parent cell
The mechanism for separating sister chromatids is virtually _______ in meiosis ii and mitosis.
identical
3 Events unique to Meiosis (all occuring in meiosis I)
1. Synapsis and crossing over in prophase I
2. At the metaphase plate, there are paired homologous chromosomes (tetrads), instead of individual replicated chromosomes.
3. Anaphase I : homologous chromosomes, instead of sister chromatids separate
Changes in an organisms DNA are known as ___
mutations
Mutations create different versions of genes called _____.
Alleles