716 terms

MCAt cell biology 1

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Fermentation
/anaerobic process that facilitates the continuation of glycolysis and produces no ATP
'Nucleus
Nucleus /- controls activity of the cell, including division
- surrounded by a nuclear membrane/envelope that maintains distinct environment from cytoplasm
- nuclear membranes have nuclear pores for two way material exchange
- contains DNA
- histones: structural proteins that form chromosomes
- nucleolus: dense structure in the nucleus where ribosomal RNA (rRNA) synthesis occurstrans-stack /portion of golgi furthest from the ER where vesicles are sent out to destination
3 jobs of the cell membrane
protect, give shape, let materials in and out
9+2 conformation
cilia/flagella cross section has what conformation?
acetyl coa
The entry compound for the Krebs cycle in cellular respiration; formed from a fragment of pyruvate attached to a coenzyme.
acid hydrolases
enzymes that degrade various macromolecules and that require an acidic pH to function properly. found within the lysosomes of cells.
Acrosome
- cap-like structure, over the anterior half of mature spermss head
- derived from Golgi apparatus
- contains enzymes to penetrate the tough outer covering of the ovum
- once in contact with ovum cell membrane, sperm forms a tubelike structure called the acrosomal process
- acrosomal process extends and fuses with ovum and enters the ovum
Actin
The primary component of microfilaments
Active site
- an area on each enzyme to which the substrate bonds to form an enzyme-substrate complex
- has a three dimensional shape into which the substrate fits and held at a particular orientation
Active Site
the specific location where a substrate binds on an enzyme
Active Transport
- net movement of dissolved particles against their concentration gradient
- need help from transport proteins
- requires energy
- required to maintain membrane potentials in specialized cells (ex: neurons)
- types of molecules transported: polar molecules/ions (Na+, Cl-, K+, etc)
active transport
movement of a molecule that requires energy since it is from low to high concentration
Active Transport
Movement of particles from a region of particles against a concentration gradient from low to high, utilizing energy.
active transport
the movement of molecules through the plasma membrane against their concentration gradients.
Active Transport
transport of a substance (as a protein or drug) across a cell membrane against the concentration gradient
Adenine
A nitrogen base that makes up the "rungs" of the DNA ladder;Pairs with Thymine
ADP
- adenosine diphosphate
- Pi: inorganic phosphate
- ATP --> ADP + Pi + 7 kcal/mole
- the 7 kcal/mole provides energy for endergonic/endothermic reactions like muscle contraction, motility and active transport across plasma membranes
Alcohol Fermentation
- occurs in yeast and bacteria only
- pyruvate produced in glycolysis is decarboxylated to acetaldehyde, then reduced by NADH in step 5 of glycolysis to yield ethanol
- pyruvate --> acetaldehyde --> ethanol
Allosteric Effects
- allosteric enzyme oscillates between two configuration (active site that can catalyze a reaction and inactive site that can
alpha amino acid
the amino and carboxyl groups are attached to the same carbon also known as the alpha carbon. Called this because the amine is attached to the carbon in the alpha position.
Alternate Energy Sources
- when glucose supplies run low, the body uses these (in order): carbohydrates, fats and proteins
- these are first converted to either glucose or glucose intermediates, which can be degraded in the glycolytic pathway and TCA cycle
amino acid residue
an amino acid in a polypeptide that is not the N or C terminal AA. This refers to every amino acid in a polypeptide chain.
AMP
- adenosine monophosphate
- PPi: phyrophosphate
- ATP --> AMP + PPi + 7 kcal/mole
Anaphase
- sister chromatids separate
- telomeres are the last part of the chromatids to separate
anaphase
phase of mitosis in which sister chromatids are pulled to opposite sides of the cell
anaphase
the third phase of mitosis, during which the chromosome pairs separate and move toward opposite poles
anaphase
the third phase of mitosis; replicated chromosomes are split apart at their centromeres and moved to opposite sides of the cell.
Anaphase
Third phase of Mitosis;Centromeres divide which separates the Chromatids, new Chromosomes move to opposite ends of cell, and the cell elongates.
Anaphase I
- disjunction: homologous pairs separate and are pulled to opposite poles of the cell
- distribution of homologous chromosomes to intermediate daughter cells are random
Anaphase II
- sister chromatids are pulled to opposite poles by the spindle fibers
Apoenzyme
- an enzyme devoid of its necessary cofactor
- catalytically inactive
apoptosis
Programmed cell death.
Asexual Reproduction
- essentially genetic carbon copies of parent cells
- identical to parent cells except for random mutations
- different types: binary fission, budding, regeneration, parthenogenesis
asexual reproduction
a reproductive process that involves only one parent and produces offspring that are identical to the parent
asexual reproduction
a reproductive process that involves only one parent and produces offspring that are identical to the parent
ATP
- adenosine triphosphate
- cell
ATP Generation and the Proton Pump
- there are energy losses as electrons are transferred from one complex to the next, this energy is then used to synthesize 1 ATP per complex
- since we have 3 complexes, we generate 3 ATP
- NADH delivers its electrons to NADH dehydrogenase complex, so for each NADH = 3 ATP
- FADH₂ bypasses the NADH dehydrogenase complex and delivers directly to carrier Q (ubiquinone), which is between complex 1 and 2, so each FADH₂ = 2 ATP
ATP Synthetase
Complex enzyme, in the inner mitochondrial membrane, that permits protons to re-enter the mitochondria and synthesizes ATP using the released energy.
Autolysis
"Cell suicide" by rupturing of lysosome membranes
Autolysis
self-digestion occurring in plant and animal tissues, particularly after they have ceased to function properly
autophagy
self-eating.
autophagy
self-eating.
Autoradiography
- uses radioactive molecules to trace and identify cell structures and biochemical activity
- can be used to study protein synthesis
- similar techniques are used to study mechanisms of DNA & RNA synthesis
Autoradiography Preparation
- cells are exposed to a radioactive compound for a brief, measured period of time
- cells are incubated, fixed at various intervals and processed for microscopy
- each preparation is covered with a film of photographic emulsion
- preparations must be kept in the dark for several days while radioactive compound decays
- the emulsion is then developed
- dark silver grains reveal the distribution of radioactivity within the specimen
Autotrophic
- green plants
- convert sunlight into bond energy stored in the bonds of organic compounds (glucose) in the anabolic process of photosythesis
- don
bacteria
have cell walls , a cell membrane, cytoplasm, ribosomes, and sometimes flagella. Also respiration occurs at the cell emebrane.
Bacteriophages
- viruses that exclusively infect bacteria
- injects its nucleic acid into a bacterial cell, the phage capsid doesnt enter the cell
Bacteriophages
Viruses that can only infect bacteria.
Bacteriophages
viruses that infect bacteria
Binary Fission
- a simple form of asexual reproduction in prokaryotes
- circular chromosome replicates
- a new plasma membrane and cell wall grow inward along the midline of the cell, dividing it into two
- each daughter cell contains a duplicate of the parent chromosome
Binary Fission
- prokaryotesway of of cell division
- a type of asexual reproduction
- splits into two equal halves, each daughter cell receives a complete copy of the original chromosome
Binary fission
A replication process for prokaryotes, also used by mitochondria
binding of ligand causes GDP to be converted to GTP, which causes the activation of cAMP
Explain G-protein linked receptors.
Bound ribosomes
Ribosomes found on the endoplasmic reticulum
Budding
- replication of the nucleus followed by unequal cytokinesis
- the cell membrane pinches inward to form a new cell that is smaller in size but genetically identical to the parent cell
- can grow to an adult size
- new cell may separate immediately from the parent or remain attached to it
- occurs in hydra and yeast
cAMP
protein that activate dependent kinases in second messenger cascade that is a universal hunger signal b/c its the second messenger for epi and glucagon
cancer
disorder in which some of the bodys own cells lose the ability to control growth
cancer
disorder in which some of the bodys own cells lose the ability to control growth
cancer
mutation in protein that regulates progression of cell cycle
cancer
uncontrolled cell division
Capsid
- virus
Capsid
A protein sheath that surrounds the nucleic acid core in a virus
Carbohydrates
- disaccharides are hydrolyzed into monosaccharides
- then converted into glucose or glycolytic intermediates
- glycogen in the liver can be converted into glucose 6-phosphate, a glycolytic intermediate
Carrier Coenzymes
- NAD⁺, FAD, NADP⁺
- transport the high energy electrons of the hydrogen atoms to a series of carrier moelcules on the inner mitochondrial membrane (electron transport chain)
Carrier proteins
Allow larger charged molecules to cross the cell membrane.integral membrane proteins that undergo a conformational change to move a molecule from one side of the membrane to another.
catalase
the primary enzyme in peroxisomes, that catalyzes the hydrolysis of hydrogen peroxide into water and oxygen.
Catalysts
Substances that reduce the activation energy of a chemical reaction.
catalytic receptors
these have an enzymatic active site on the cytoplasmic side of the membrane that is activated when a ligand binds at the extracellular surface.
cell
basic unit of structure and function in living things
Cell adhesion molecules
Membrane proteins that allow cells to adhere to one another.
Cell adhesion molecules (CAMs)
Proteins that contribute to cell reconition and adhesion
cell adhesion proteins
proteins that contribute to cell recognition and adhesion.
cell cycle
cell grows, prepares to divide, then divides to start growth process again; interphase + M phase
Cell Cycle
Process that cells go through over and over in which they increase in size and in number that allows an organism to grow bigger.
cell cycle
the regular sequence of growth and division that cells undergo
cell differentiation
cells perform different jobs and specialized tasks
Cell Division
- a process where a cell doubles its organelles and cytoplasm, replicates its DNA and then divides in two
- unicellular organism: reproduction
- multicellular organism: growth, development & replace old cells
cell division
division of a parent cell into daughter cells
cell division
process by which cells reproduce
Cell membrane
Encloses the cell; consists of a phospholipid bilayer
cell membrane
thin structure that surrounds a cell
Cell Plate
Vesicle like material that develops in the middle of two dividing daughter cells that will become two different cell membranes; one for each daughter cell.
cell respiration
the process of using oxygen to release energy from food
cell surface receptor
an integral membrane protein that binds extracellular signaling molecules, such as hormones and peptides.
Cell Wall
- tough outer cell wall
- protects the cell from external stimuli and desiccation
- only on plant cells
cell wall
outer, nonliving part of a plant cell
Cell wall
Tough outer layer of a cell made of cellulose, chitin, or other materials
Cell
Plasma Membrane /- encloses the cell and composed of phospholipid bilayer
- outside: hydrophillic (polar) phosphoric acid
- inside: hydrophobic (non-polar) fatty acid
- selective permeability: small non-polar molecules pass through/diffuse freely, charged ions, proteins & carbohydrates dont (need carrier proteins to cross)
- cholesterol molecules: often embedded in hydrophobic interior & contribute to fluidity
- receptors: complex proteins glycoproteins embedded in - membrane with biding sites, may carry molecule into the cell via pinocytosis
Cellular Metabolism
- the sum total of all chemical reactions that take place in a cell
- either anabolic (require energy) or catabolic (release energy)
Cellular Respiration
- most efficient catabolic pathway to harvest energy stored in glucose
- occurs in mitochondrion and catalyzed by reaction specific enzymes
- produces 36-38 ATP
- aerobic, O₂ acts as the final acceptor of electrons that are passed from carrier to carrier during the final stage of glucose oxidation
- three stages: pyruvate decarboxylation, citric acid cycle and electron transport chain
cellulose
hard, nonliving material that makes up the cell wall of a plant cell
cellulose
hard, nonliving material that makes up the cell wall of a plant cell
Centrifugation
- used to separate cells or mixtures of cells without destroying them in process
- lower speed: cell mixtures separate into layers on the basis of cell type
- high speed: fragmented cells
centriole
a structure composed of a ring of nine microtuble triplets, found at the MTOC of a cell; they duplicate during cell division, and sere as the organizing center for the mitotic spindle.
centriole
structure that helps to form the spindle
Centrioles
- specialized type of microtubule involved in spindle organization during cell division
- not bound by a membrane
- only on animal cells
- oriented at right angles to each other and lie in a region called the centrosome
- direct separation of chromosomes during cell division
- composed of microtubules
Centrioles
A set of cylinder shaped structures, that are copied during Interphase, used during Mitosis to anchor Spindle Fibers.
Centrioles
One of two tiny structures located in the cytoplasm of animal cells near the nuclear envelope; play a role in cell division.
Centrioles
Specialized type of microtubule used in cell division in animal cells
centrioles
structures that are located within the microtubule organizing center and forms microtubules during mitosis to attach to chromosome
centrisomes
located in the centrosome area, and are found in animal cells but not in plant cells.
centromere
a structure near the middle of eukaryotic chromosomes to which the fibers of the mitotic spindle attach during cell division.
Centromere
Small structure that holds the two chromatids of a chromosome together; It will divide when it is time for the chromatids to separate.
centromere
structure at the center of a chromosome that ensures replication is done properly
centromere
the region of the chromosome that holds the two sister chromatids together during mitosis
Centrosome
Region where centrioles are located
Cervix
- lower, narrow end of the uterus
- connects with the vaginal canal
channel protein
an integral membrane protein that selectively allows molecules across the plasma membrane.
channel proteins
proteins that selectively allow ions or molecules to cross the plasma membrane
channels
highly specific holes that distinguish by element type
Chiasmata
where chromosomes are joined
chlorophyll
green material in chloroplasts that is needed for plants to make food
chloroplast
green structure in a plant cell that contains chlorophyll
Chloroplast
Site of photosynthesis in plants. Contains chlorophyll, is semiautonomous and has two cell membranes.
Chloroplasts (plastids)
The site of photosythesis in plant cells (semiautonomous)
cholesterol
a large, ring-shaped lipid found in cell membranes; the precursor for steroid hormones.
Chromatid
One rod of strand of a chromosome it is an exact copy of the other chromatid in the chromosome.;Two chromatids make up one chromosome
Chromatin
- granular DNA during interphase
Chromatin
Thin strands of DNA that holds instructions for all cellular activities; The form DNA takes when it is actively directing the cell.
Chromosome
Double rod of condensed chromatin.
chromosome
threadlike structure within the nucleus containing the genetic information that is passed from one generation of cells to the next
Chromosome Movement
- dependent on these cytoplasmic organelles
- centrioles: found in pairs, cylindrical organelles
- centrosome: an area outside the interphase nucleus
- spindle fibers: composed of microtubules, appears near each pair of centrioles, radiate outward.
- asters: spidle fibers in radiating structure
- spindle apparatus: asters extending toward the center of the nucleus, shortens to move chromosomes toward
opposite poles of the cell during the later stages of mitosis
chromosomes
cell parts that determine what traits a living thing will have
Chromosomes
Linear strands of DNA located in the nucleus
chylomicrons
lipoproteins formed in the cells lining the small intestine following absorption of fats. they are made in the small intestinal cells and transpost dietary lipids to the liver.
Cilia and Flagella
Specialized arrangements of microtubles used for cell motility
cis-stack
portion of golgi nearest the ER where vesicles from the ER are received
clathrin
a fibrous protein found on the intracellular side of the plasma membrane that helps to invaginate the membrane.
clathrin
What is the protein necessary for endosome formation?
Cleavage Furrow
A groove formed in the cell membrane of an animal cell going through cytokinesis;It will deepen as fibers contract ,until the cell is split into two cells.
Coenzymes
organic substances that assist in enzyme activity such as vitamins
Cofactor
inorganic substances that assist in enzyme activity such as FE2+
Cofactors
- nonprotein molecule required to make enzymes catalytically active
- aid in binding the substrate to the enzyme or stabilizing the enzyme in an active formation
- can be found to their enzymes by weak noncovalent bonds or strong covalent bonds
- prosthetic groups: tightly bound cofactors
Competitive Inhibition
occurs when two molecules, one of which is the substrate and one of which is an inhibitor, compete for the enzyme
s active site
...
Competitive Inhibitors
- compete with the substrate directly by binding into the active site of the enzyme
- have similar structure to substrate
reversible with increased concentrations of substrate
Compound Light Microscope
- requires contrast between cells and cell structures
- contrast is obtained through staining techniques that results in cell death
- use various stains and dyes
ex: hematoxylin (reveals the distribution of DNA and RNA within a cell due to its affinity for negatively charged molecules)
Connective Tissue
- involved in body support
- specialized connective tissues: bone, cartilage, tendons, ligaments, adipose tissue and blood
constitutive secretory pathway
continuous secretion of soluble proteins newly synthesized lipids and proteins for the plasma membrane
Corona Radiata
- outer layer of the oocyte cell membrane
Cortical Reaction
- triggered by acrosomal reaction
- calcium ions released into the cytoplasm, initates a series of reaction to form the fertilization membrane
- calcium ion also stimulates increase in ovum
crinophagy
lysosomal digestion of unneeded secretory products
Cristae
An infolding of the inner membrane of a mitochondrion that houses the electron transport chain and the enzyme catalyzing the synthesis of ATP.
Cristae
The folds of the inner membrane of mitochondria, contain electron transport chain proteins
cristae
the folds of the inner membrane of the mitochondria.
crossing-over
process by which homologous chromosomes exchange pieces, resulting in greater genetic variety
crossing-over
process by which homologous chromosomes exchange pieces, resulting in greater genetic variety
cyclic AMP
cAMP; a cyclic version of adenosine monophosphate, where the phosphate is esterified to both the 5 and the 3 carbons, forming a ring.
cyclin
one of a family of proteins that regulates the cell cycle in eukaryotic cells
Cytochrome
a class of hemoprotein whose principle biological function is as carriers of electrons
Cytochrome a₃
- last carrier of the ETC
- passes its electron to the final eectron acceptor, O₂
- in addition, O₂ picks up a pair of hydrogen ions from the surrounding medium and forms water
- 2H⁺ + 2e⁻ + ½ O₂ --> H₂O
Cytochromes
- most of the molecules of the ETC
- electron carriers that resemble hemoglobin in structure of their active site
- functional unit contains a central iron atom, which is capable of undergoing a reversible redox reaction
Cytokinesis
- happens at the end of telophase
- cytoplasm divides into two daughter cells
- in animal cells, a cleavage furrow forms, cell membrane indents along the equator of the cell and cell split
cytokinesis
division of the cytoplasm (cytosol and organelles)
cytokinesis
division of the cytoplasm (cytosol and organelles)
cytokinesis
division of the cytoplasm during cell division
cytokinesis
the phase of mitosis during which the cell physically splits into two daughter cells.
Cytokinesis
The third and final stage of the cell cycle in which the cells cytoplasm divides, distributing the organelles into each of the two new cells.
Cytokinesis
The third and final stage of the cell cycle in which the cells cytoplasm divides, distributing the organelles into each of the two new cells.
...
...
cytokinesus ends and the reversal of prophase occurs
What occurs during telophase?
Cytoplasm
Gel like fluid that is in constant motion an fills the cell; organelles are found here.
cytoplasm
gel like substance inside cell that holds the organelles
Cytoplasm
Organelles suspended in cytosol
cytoplasm
Where does fatty acid biosynthesis occur?
Cytosine
A nitrogen base that makes up the "rungs" of the DNA ladder;Pairs with Guanine
Cytoskeleton
- found in the cytosol
- composed of microtubules, microfilaments, intermediate fibers
- give cell shape and anchor organelles
- aid intracellular transport
Cytoskeleton
- gives cell mechanical support, maintains its shape and functions in cell motility
- composed of microtubules, mirofilaments and intermediate filaments
Cytoskeleton
a microscopic network of actin filaments and microtubules in the cytoplasm of many living cells that gives the cell shape and coherence
cytoskeleton
Found in the cytosol and contains, microfilaments, microtubules, and intermediate fibers. Gives the cell its shape and and anchor organelles. Functions in intracellular transport.
Cytoskeleton
Gives the cell mechanical support, maintains shape and functions in motility. Composed of microtubules, microfilaments and intermediate filaments.
Cytoskeleton
Microtubules, microfilaments, and intermediate filaments
Cytosol
A semifluid medium, part of cytoplasm
cytosol
semifluid medium containing organelles.
cytosol
Where in the cell does all translation begin?
daughter cells
new cells produced by cell division
daughter cells
new cells produced by cell division
Daughter Cells
New identical cells created as a result of one cell undergoing cellular division.
Daughter Cells
New identical cells created as a result of one cell undergoing cellular division.
dehydration synthesis
A chemical reaction in which two molecules covalently bond to each other with the removal of a water molecule.
denaturation
For proteins, a process in which a protein unravels and loses its native conformation, thereby becoming biologically inactive. For DNA, the separation of the two strands of the double helix. Denaturation occurs under extreme conditions of pH, salt concentration, and temperature. Disrupts everything but primary structure.
Denaturization
the breakdown in an enzymes shape due to the disruption of hydrogen bonds that maintain the enzymes structure
Deoxyribose
The sugar molecule that makes up part of the sides of a DNA molecule.
Deoxyribose
The sugar molecule that makes up part of the sides of a DNA molecule.
desmosome
a general cell junction, used primarily for adhesion.
desmosome
general adhesion junctions that do not form a complete seal
diffusion
movement of material from an area where molecules are crowded to an area where they are less crowded
diffusion
movement of solute particles from high concentration area to a low concentration area until solute in distributed evenly
diffusion
the movement of a particle from its region of high concentration to its region of low concentration.
diffusion rate is inversely proportional to membrane thickness
What is the affect of membrane thickness on rate of diffusion?
Dizygotic (fraternal) Twin
- results when two ova are released in one ovarian cycle
- fertilized by two different sperm
- two embryos implant in the uterine wall individually
- each develops its own placenta, amnion and chorion
- share characteristics in the level of siblings
DNA
Genetic material that looks like twisted ladder which is made up of alternating molecules of deoxyribose and phosphates on the sides and paired nitrogen bases as the "rungs".
DNA
Nucleic Acids that are the genetic material;Directs all cell activity and is passed from parent to offspring.
Double Helix
The scientific name for the twisted ladder structure of the DNA molecule.
Effects of Concentrations
- when [S] is low vs [E], many active sites are unoccupied, reaction rate is low
- increase [S] means proportional increase in rate of reaction because unoccupied active sites on enzyme will readily bind
Effects of pH
- maximal activity of human enzymes occurs around pH 7.4, which is the pH of most body fluids and tissues
- some exceptions: pleural fluid (pH 7.6), pepsin (works best in acidic condition of the stomach, pH 2), and pancreatic enzymes (works in alkaline conditions of small intestine, pH 8.5)
Effects of Temperature
- rates of enzyme-catalyzed reactions tend to double for every 10°C increase until optimal temperature is reached
- for most enzymes operating in the human body, optimal temperature is 37°C
- any higher, the enzymes become denatured
eicosanoid
a class of fatty acids that regulate blood vessel vasodilation, temperature elevation, WBC activation, and other physiologic processes involved in immunity.
Electron Carriers
- categorized into three large protein complexes:
a) NADH dehydrogenase
b) the b-c₁ complex
c) cytochrome oxidase
Electron Microscope
- uses a beam of electrons to allow a thousandfold higher magnification compared to light microscopy
- can only examine dead specimens
- preparation: fix & section tissues, sometimes stained with solutions of heavy metals
Electron Transport Chain
A sequence of electron carrier molecules (membrane proteins) that shuttle electrons during the redox reactions that release energy used to make ATP.
Electron Transport Chain (ETC)
- a complex carrier mechanism located on the inside of the inner mitochondrial membrane
- two parts: electron transfer and ATP generation + the proton pump
Endocytosis
- process in which the cell membrane invaginates, forming a vesicle that contains extracellular medium
endocytosis
membrane bound vesicle that will be digested by lysosomes that depends on a cell surface receptor to initiate a response that requires ATP
Endocytosis
process by which a cell takes material into the cell by infolding of the cell membrane
Endoplasmic Reticulum
- a network of membrane-enclosed spaces connected at points with the nuclear membrane
- function: transport materials throughout the cell, mainly secretion
- smooth ER: lipid synthesis
- rough ER: protein synthesis
- these proteins cross to smooth ER, secreted into cytoplasmic vesicles & transported to golgi apparatus
endoplasmic reticulum
a cell structure that forms a maze of passageways in which proteins and other materials are carried from one part of the cell to another
endoplasmic reticulum
a cell structure that forms a maze of passageways in which proteins and other materials are carried from one part of the cell to another
Endoplasmic Reticulum
Membrane-enclosed spaces connected to the nuclear membrane
endoplasmic reticulum
transport system of the cell- like highways
endoplasmic reticulum
transport system of the cell- like highways
Energy Carriers
- molecular carriers used by the cell to shuttle energy between reactions
- ATP, NAD⁺, FAD
Enzyme Kinetics
- depends on concentration of the enzyme and the substrate
- depends on environmental variables (temperatures, pH)
Enzyme Specificity
refers to the fact that an enzyme is usually specific to one reaction
Enzymes
- protein catalysts that accelerate reactions
- lower activation energy
- doesnt change the equilibrium or free energy (ΔG), only changes the rate at which it is attained
- not consumed or changed (appears in reactants & products)
- reactions are reversible, product synthesized can be decomposed by the same enzyme
- pH & temperature sensitive
Epididymus
where sperm acquire motility and stored here till ejaculation
Epithelial Tissue
- covers the surfaces of the body
- lines the cavities
- protects against injury, invasion and dessication
- involved in absorption, secretion and sensation
epithelium
membranous tissue covering internal organs and other internal surfaces of the body.
epithelium
membranous tissue covering internal organs and other internal surfaces of the body.
essential amino acid
Amino acids that an animal cannot synthesize itself and must be obtained from food. Eight of these are essential in the human adult.
ETC without )₂
- without oxygen, ETC becomes backlogged with electrons and NAD⁺ can
euchromatin
a region of DNA that is uncoiled and undergoing active transcription into RNA
euchromatin
a region of DNA that is uncoiled and undergoing active transcription into RNA
euchromatin
more loosely packed chromatin that allows for genes to be activated
Eukaryotes
- typically bounded by cell membrane and contains cytoplasm
- Cytosol: fluid component of the cytoplasm and consist free proteins, nutrients & other solutes
- genetic material (linear strands of DNA) organized into chromosomes, located in the nucleus
- Centrioles: found in animal cells but not in plant cells
eukaryotes
All multicellular and unicellular nonbacteria organisms. Is bounded by a cell membrane and contains cytoplasm. cytoplasm contains organellessuspended in a semifluid mediumcalled cytosol. The genetic material consists of linear strands of DNA organized into chromosomes located in the nucleus.
eukaryotic genome
structure organized in linear chromosomes of dsDNA
Exocytosis
- a vesicle within the cell fuses with the cell membrane and releases its contents to the outside
- in both endocytosis and exocytosis, the material never actually crosses through the cell membrane
Exocytosis
process by which a cell releases large amounts of material
Exocytosis
The process by which vesicles release contents to the cells exterior
exocytosis
the secretion of a cellular product to the extracellular medium through a secretory vesicle.
Faciliated Diffusion
- passive transport
- net movement of dissolved particles down their concentration gradient
- need help from carrier molecules
- types of molecules transported: large/non-polar (glucose)
facilitated diffusion
movement of solute across the plasma membrane via channel proteins when membrane is impermeable to that solute
Facilitated Diffusion
movement of specific molecules across cell membranes through protein channels
Facilitated Diffusion
Passive movement of particles from a region of higher concentration to a region of lower concentration using carrier molecules, without expending energy.
FAD
flavin adenine dinucleotide
FAD+
flavinine adenine dinucleotide, a compound that acts as a hydrogen acceptor in dehydrogenation reactions
FADH
electrons are transferred to an electron acceptor called FAD, making this molecule(another type of electron carrier).
Fate of Pyruvate
- anaerobic: pyruvate is reduced through fermentation
- aerobic: pyruvate is further oxidized during cell respiration in mitochondria
Fats
- stored in adipose tissue in the form of triglyceride
- when needed, they are hydrolyzed by lipases to fatty acids and glycerol, and are carried by the blood to other tissues for oxidation
- glycerol can be converted into PGAL
- a fatty acid must be "activated" first in the cytoplasm, this requires 2 ATP
- on active, it is transorted into mitochondrion and taken through a series of "beta-oxidation cycles" that convert it into two carbon fragments, then converted to acetyl CoA, which enter TCA cycle.
- each round of beta oxidation generates 1 NADH and 1 FADH₂
-fats yield the most ATP per gram
fatty acids
building blocks of lipids., chains of carbon atoms bonded to hydrogen atoms. Typically there is an even number of carbons with the maximum in humans being 24. Can be saturated or unsaturated.
Feedback Inhibition
- this feedback process allows organisms to avoid overproduction of metabolites
Female Reproductive Anatomy
- once a month, an immature ovum is released from the ovary into the abdominal cavity and drawn into the nearby fallopian tube
- inner surface of the fallopian tube is lined with cilia that move the ovum into and along the tube and toward the uterus
- mammalian females reproductive and excretory systems are distinct from one another (urethra and vagina arent connected)
Fermentation
- regeneration NAD⁺ to continue glycolysis without O₂
- reduce pyruvate to ethanol or lactic acid
- fermentation produces only 2 ATP per glucose molecule
Fertilization
- happened 12-24 hours after ovulation
- occurs in the lateral, widest portion of the fallopian tube
- sperm travels through vaginal canal, cervix, uterus, and into the fallopian tubes to reach the ovum
- sperm penetrates corona radiata, then zona pellucida, contact with ovum cell membrane, become acrosomal process, fuse sperm with ovum
- sperm nucleus enters ovums cytoplasm and ovum completes meiosis II
Fertilization Membrane
- hard layer that surrounds the ovum cell membrane
- prevents multiple fertilizations
fluid mosaic model
mosaic of lipids and proteins which are free to move back and forth
Fluid mosaic model
The currently accepted model for the cell membrane
FMN (flavin mononuclotide)
- first molecule of the ETC
- reduced when it accepts electrons from NADH, therefore oxidizing NADH to NAD⁺
Follicles
- multilayered sac of cells that contains, nourishes and protects and immature ovum
- follicle cells produce estrogen
forces creating tertiary structure
Covalent disulfide bonds between two cystein amino acids,electrostatic interactions between acidic and basic side cains, hydrogen bonds, van derwaals forces, hydrophobic side chains pushed away from water.
Free ribosomes
Ribosomes found in the cytoplasm
G-protein-linked receptor
a cell surface receptor associated with an intracellular protein that binds and hydrolyzes GTP.
G-protein-linked receptor
a cell surface receptor associated with an intracellular protein that binds and hydrolyzes GTP.
G1 phase
stage of interphase in which cell grows and performs its normal functions
G1-phase
growth phase of cell cycle that functions to increase cell size to accommodate replicated genome
G2 phase
stage of interphase in which cell duplicates its cytosol and organelles
G2-phase
growth phase of cell cycle that functions prepare cell for division in M-phase
gamete
sex cell, sperm or egg
Gametes
- sperm and egg
- produced in gonads
gap junction
a junction formed between cells, consisting of a protein channel called a connexon on each of the two cells, that connect to form a single channel between the cytoplasms of both cells.
gap junctions
junctions that allow cell-to-cell communication
gap phase
a phase in the cycle between mitosis and S phase, or between S phase and mitosis; cell undergoes normal activity and growth.
globular protein
a protein that folds into a compact shape so that the polar and ionic amino acids are on the outside and the nonpolar amino acids are on the inside. They function as enzymes, hormones, membrane pumps and channels, membrane receptors andinter/intracellular transport and storage molecules.
Glucose Catabolism
occurs in two stages:
a) glycolysis
b) cellular respiration
Glucose Catabolism - event and location
Event --> Location

glycolysis -- cytoplasm
fermentation -- cytoplasm
pyruvate to acetyl CoA -- mitochondrial matrix
TCA cycle -- mitochondrial matrix
ETC - inner mintochondrial matrix
glycolipid
a membrane lipid consisting of a glycerol molecule esterified to two fatty acid chains and sugar molecule.
glycolipid
a membrane lipid consisting of a glycerol molecule esterified to two fatty acid chains and sugar molecule.
glycolipids
lipid substances with linked sugar groups that are key structural elements in cell membranes and precursors of other biologically active molecules important in cell signaling.. Are also amphipathic and are found in myelinated cells composing the human nervous system.
Glycolysis
- series of reactions that lead to the oxidative breakdown of glucose into two molecules of pyruvate, the production of ATP and reduction of NAD⁺ into NADH
- occurs in cytoplasm
- mediated by specific enzymes
glycolysis
a metabolic process that breaks down carbohydrates and sugars through a series of reactions to either pyruvic acid or lactic acid and release energy for the body in the form of ATP. produces 2 net ATP
Glycolytic Pathway
- fructose 1,6-diphosphate is split into dihydroxyacetone and glyceraldehyde 3-phosphate (PGAL)
- dihydroxyacetone is isomerized into PGAL
- two molecules of PGAL is formed per molecule of glucose
- 1 glucose = 2 pyruvate
- net production of 2 ATP/mole of glucose (4 generated, 2 used up)
glycoprotein
Proteins with short chains of sugars attached to them; in eukaryotic cells they are important membrane proteins that allow cell-cell recognition and interaction.
Glyoxisomes
Found in fat tissue of seedlings, used to convert fats to sugars
Glyoxysomes
Important in germinating plants
golgi
organelle that serves to sort and modify proteins as part of the secretory pathway
Golgi Apparatus
- stack of membrane-enclosed sacs
- receives vesicles from smooth ER, modifies them, repackages into vesicles & distributes them
- usually active in distributing new materials to cell surface
- exocytosis: when golgi apparatus
golgi apparatus
a stack of membranes found near the rough ER in eukaryotic cells that is involved in the secretory pathway.
Golgi Apparatus
stack of membranes in the cell that modifies, sorts, and packages proteins from the endoplasmic reticulum
Golgi Apparatus
Stack of sacs that receives contents of the ER, modifies and repackages them, and distributes them
Gonads
- male: testes
- female: ovaries
Growth
The process that cells go through to increase the size of the cell.
growth factor
one of a group of external regulatory proteins that stimulate the growth and division of cells
Guanine
A nitrogen base that makes up the "rungs" of the DNA ladder;Pairs with cytosine
Guanine
A nitrogen base that makes up the "rungs" of the DNA ladder;Pairs with cytosine
Gyloxysomes
- a type of microbodies
- usually found in fat tissue of germinating seedlings
- used by the seedling to convert fats into sugars until the seedling is mature enough to make its own sugar through photosynthesis
G₁ Stage (presynthetic gap)
- intense biochemical activity and growth
- cell doubles in size and new organelles are produced
- passing "restriction point", where a cell is committed to continue through the rest of the cell cycle and divide
- some cells like skeletal muscle cells and nerve cells never pass this point, and enter a nondividng phase sometimes referred to as G₀
- 2N number of chromosomes
G₂ Stage (postsynthetic gap)
- cell continues to grow in size
- assembly of new organelles and other cell structures continues
heat, therefore an increase in body temperature
What will the ultimate product of breakdown the H gradient be?
Helicase
Enzyme that unwinds and separates the DNA molecule during replication.
heterochromatin
densely packed chromatin that is inaccessible to enzymes, so genes are inactive
heterochromatin
Eukaryotic chromatin that remains highly compacted during interphase and is generally not transcribed.
Heterotrophic
- obtain energy catabolically
- break down organic nutrients that must be ingested
higher outside the cell
Is the concentration of Ca higher or lower outside the cell?
higher outside the cell
Is the concentration of Cl high inside or outside the cell?
Histones
protein molecules around which DNA is tightly coiled in chromatin
Histones
Proteins that complex with and stabilize DNA in chromosomes
Holoenzyme
an enzyme containing its cofactor
Homologous Chromosomes
chromosomes that code for the same trait, one inherited from each parent
homologous chromosomes
equivalent chromosomes that are not identical that play NNNOOOO role in mitosis
hydrogen bond
weak chemical bond formed by the attraction of positively charged hydrogen atoms to other negatively charged atoms.
hydrolysis
a chemical process in which a compound is broken down and changed into other compounds by taking up the elements of water. Breaks apart most macromolecules of living cells.
Hydrophilic
Region of phospholipid that faces interior and exterior of cell
hydrophobic
lacking affinity for water
Hydrophobic
Region of phospholipid bilayer that faces intramembrane space
hydrostatic pressure
pressure exerted by the movement of water across a semipermeable barrier from low solute concentration to high solute concentration
hypertonic
area of relative high solute concentration, where water will flow into via osmosis
Hypertonic (in respect to another liquid)
- has a higher solute concentration
- water will flow into the hypertonic liquid
Hypotonic (in respect to another liquid)
- has a lower solute concentration
- water will flow out of hypotonic liquid, into the higher concentrated liquid
I Pee on the MAT
Pneumonic for mitosis
inclusion
lifeless storage sites for energy and reservoirs for structural building blocks
Inhibition
- interferences with enzymatic activity
- categorized as: feedback, competitive and noncompetitive inhibition
inner mitochondrial membrane
site of mitochondrion that is impermeable to protons and is where ETC takes place
integral membrane protein
a protein imbedded in the lipid bilayer of a cell.
integral membrane protein
a protein imbedded in the lipid bilayer of a cell.
integral proteins
proteins embedded in a membrane that are held in place by hydrophobic interactions
Intermediate filaments
- collection of fibers involved in maintenace of cytoskeletal integrity
- diameter falls between microtubules and microfilaments
intermediate filaments
cytoskeletal filaments with a diameter in between that of the microtuble and the microfilament; tend to play structural roles.
intermediate filaments
cytoskeletal filaments with a diameter in between that of the microtuble and the microfilament; tend to play structural roles.
Intermembrane space
In mitochondria, the area between the inner and outer membranes
Intermembrane Space
the fluid filled space between the inner and outer mitochondrial membranes
Interphase
- the longest part of the cell cycle
- a cell normally spends at least 90% of the cycle in interphase
interphase
cell grows, performs its normal functions, and prepares for division; consists of G1, S, and G2 phases
interphase
cell grows, performs its normal functions, and prepares for division; consists of G1, S, and G2 phases
interphase
period of the cell cycle between cell divisions
interphase
period of the cell cycle between cell divisions
Interphase
the combination of G1, S, and G2 phases of the cell cycle where no division is taking place
Interphase
The first stage of the Cell Cycle; A cell will grow larger, produce needed organelles, Replicate DNA, and produce structures needed for a cell to divide.
Interphase
The first stage of the Cell Cycle; A cell will grow larger, produce needed organelles, Replicate DNA, and produce structures needed for a cell to divide.
Isotonic
- solute concentration between two liquids are equal
- no net flow of water in either direction
isotonic
two areas of equal solute concentration where osmosis does not occur
K+leak channels
channels that allow for K+ to flow out of cell interior, giving cell overall negative charge
karyotype
a display of an organism
keratin
a protein-based substance secreted by cells of the epidermis as they migrate outward; makes the cell tougher.
keratin
a protein-based substance secreted by cells of the epidermis as they migrate outward; makes the cell tougher.
kinase
an enzyme that transfers a phosphoryl group from ATP to other compounds.
kinase
an enzyme that transfers a phosphoryl group from ATP to other compounds.
kinetochore
a specialized condensed region of each chromosome that appears during mitosis where the chromatids are held together to form an X shape.
kinetochore
a specialized condensed region of each chromosome that appears during mitosis where the chromatids are held together to form an X shape.
s cycle
in all plants and animals: a series of enzymatic reactions in mitochondria involving oxidative metabolism of acetyl compounds to produce high-energy phosphate compounds that are the source of cellular energy. produces 30 ATp
Lactic Acid Fermentation
- occurs in certain fungi and bacteria and in human muscle cells during strenuous activity
- happens when oxygen supply to muscle cells lags behind the rate of glucose catabolism
- pyruvate generated is reduced to lactic acid, which can lower blood pH if accumulated, eventually becomes muscle fatigue
- oxygen debt: the amount of oxygen needed to oxidize lactic acid back to pyruvate and enters cellular respiration
ligand
a specific molecule that binds to a receptor.
ligand-gated ion channel
an ion channel that is opened or closed based on the binding of a specific ligand to the channel.
ligand-gated ion channel
an ion channel that is opened or closed based on the binding of a specific ligand to the channel.
lipids
Has low solubility in waterand high solubility in nonpolar organic solvents. They are hydrophobic and are excellent barriers seperating aqueous environments. Six major types.
lipoprotein
Large conglomerations of proteins, fats, and cholesterol that transport lipids in the bloodstream. Contains a lipid core surrounded by phospholipids and apoproteins. Are classified by their density.
Lock and Key Theory
- a model describing the formulation of an enzyme-substrate complex
- the spatial structure of an enzyme
s active site (lock) is exactly complementary to the spatial structure of its substrate (key)
...
lysosome
a eukaryotic organelle filled with digestive enzymes that is involved in digestion of macromolecules.
lysosome
a eukaryotic organelle filled with digestive enzymes that is involved in digestion of macromolecules.
Lysosome
membrane-bound sac containing digestive enzymes that can break down proteins, nucleic acids, and polysaccharides
Lysosome
Membrane-bound vesicle that contains hydrolytic enzymes used for intracellular digestion.
Lysosomes
- membrane-bound vesicles that contain hydrolytic enzymes involved in intracellular digestion
- enzymes are maximally effective at pH 5, thrives in lysosmes
- lysosome is an acidic environment distinct from neutral pH of cytosol
- fuse with endocytotic vacuoles and break down materials ingested by the cell
- aid in renewing cell
s own components by breaking down old ones to be recycled in the cytosol
- autolysis: injured
dying cell may commit suicide by rupturing the lysosome membrane & releasing its hydrolytic enzymes, which will digest cellular contents
lysosomes
organelles that contain hydrolase enzymes to digest substances
Lysosomes
Vesicles that contain hydrolytic enzymes for digestion. Contain a very acidic environment.
M phase
includes mitosis and cytokinesis.
M phase
includes mitosis and cytokinesis.
M Stage (Mitosis)
- mitosis: division and distribution of the cells DNA to its two daughter cells such that each cell receives a complete copy of the original genome
- cytokinesis: division of cytoplasm that follows
- happens on somatic cells only
- 2N --> 2N (ends up with two diploid cells)
M-phase
phase where mitosis and cytokinesis takes place
macrophages
large, non-specific phagocytic cells of the immune system.
macrophages
large, non-specific phagocytic cells of the immune system.
Male Reproductive Anatomy
- testes contain two functional components: seminiferous tubules and interstitial cells (cells of Leydig)
- sperm are produced in seminiferous tubules, nourished by Sertoli cells
- interstitial cells secrete testosterone and anderogens
- testes have to be 2-4°C lower than body temperature
Matrix
The area of the mitochondria bound by the inner membranethe interior of the mitochrondria; the site of action in the pyruvate dehydrogenase complex and the krebs cycle.
matrix
...
matrix has low [H] and inner space has high [H], similar to how prokaryotes carry out oxidative phosphorylation
What is a characteristic related to the inner mitochondrial membrane that supports symbiosis evolution of the organelle?
Maximal Velocity (Vmax)
- increases in [S] no longer increase the reaction rate
- happens at high [S]
Meiosis
- only occurs in the sex cells
- meiosis I produces two intermediate daughter cells
- meiosis II is similar to mitosis, it separates sister chromatids and results in four genetically distinct haploid gametes
meiosis
type of cell division that creates gametes; cell divides twice to create four cells that are genetically unique
meiosis
type of cell division that creates gametes; cell divides twice to create four cells that are genetically unique
Meiosis II
- doesnt occur until fertilization
- triggered when zona pellucida and corona radiata are penetrated by a sperm cell
- fertilization yields two haploid cells, a mature ovum and another polar body
- the mature ovum is a large cell containing a lot of cytoplasm, RNA, organelles and nutrients needed by a developing embryo
Meiosis II
- similar to mitosis
- not preceded by chromosomal replication
Menarche
- the first time a female gets her period
Metaphase
- chromosomes align
metaphase
phase of mitosis in which chromosomes line up in the center of the cell
metaphase
second phase of mitosis, during which the chromosomes line up across the center of the cell
Metaphase
Second phase of Mitosis;Chromosomes line up across the center of the cell, each Chromosome attaches to a Spindle Fiber.
metaphase
the second phase of mitosis; replicated chromosomes align at the center of the cell.
Metaphase I
- homolgous pairs (tetrads) align at the equatorial plane
- each pair attaches to a separate spindle fiber by its kinetochore
Metaphase II
- chromosomes line up along the equatorial plane
- centromeres divide
- chromosomes separate into pairs of sister chromatids
Michaelis constant (Km)
- (k2+k3)/k1
- low Km = high affinity for the substrate
- high Km = low affinity of the enzyme for the substrate
Michaelis-Menten Model
- E + S <--> ES 1/2 --> E + P
- k1 toward ES 1/2, k2 toward E+S, k3 toward E+P
- when reaction rate is equal to 1/2 Vmax, Km = [S]
- when [S] is less than Km, changes in [S] greatly affect the reaction rate
- at [S], [S] is larger than Km and V approaches Vmax
Microbodies
- membrane-bound organelles specialized as containers for metabolic reactions
- two types: peroxisomes and glyoxysomes
Microbodies
Membrane-bound organelles specialized as containers for metabolic reactions. (Peroxisomes and Glyoxysomes)
Microbodies
Peroxisomes and glyoxysomes
microfilament
filament composed of actin protein that have a small diameter. They perform muscle contraction, cytokinesis, and pseudopod formation
microfilament
the cytoskeleton filaments with the smallest diameter. responsible for events such as pseudopod formation and cytokinesis during mitosis.
Microfilaments
- solid rods of actin
- involved in cell movement and support
ex: muscle contraction is based on interaction of actin with myosin in muscle cells
- move materials across the plasma membrane in amoeboid movement
Microfilaments
Solid rods of actin, involved in cell movement
microtubule
hollow rods composed of alpha and beta tubulin, which form mitotic spindle, perform intracellular transport, and flagellar movement
microtubule
the largest of the cytoplasmic filaments, composed of two types of protein. dynamic fibers that form the mitotic spindle during cell division.
Microtubules
- hollow rods made up of polymerized tubulins
- radiate throughout the cell and provide it with support
- provide a framework for organelle movement within the cell
- tubulins make up mirotubules, which make up centrioles
Microtubules
Hollow rods of polymerized tubulins, provide support and network for organelle movement
Mitochondria
- sites of aerobic respiration within the cell
- suppliers of energy
- each mitochondrion is bound by an outer and inner phospholipid bilayer membrane
- is semiautonomous: contain own (circular) DNA and ribosomes, can produce own proteins and self replicate by binary fission
- believed to have been early prokaryotic cells that evolved a symbiotic relationship with ancestors of eukaryotic cells
mitochondria
organelle surrounded by a double-membrane where ATP production takes place.
mitochondria
organelle that produces ATP via kreb
mitochondria
rice-shaped structures that produce energy for a cell
mitochondria
rice-shaped structures that produce energy for a cell
Mitochondria
Site of aerobic respiration that provides the cell with a majority of its energy as ATP. Semiautonomous organelle enclosed by two membranes with an intermembrane space between them. A matrix is enclosed by the inner membrane.
Mitochondria
Sites of aerobic respiration in cells, bound by 2 membranes
Mitochondria
...
s Membrane
- outer membrane: smooth, acts as a sieve, allows molecule through based on size
- intermembrane space: area between the inner and outer membrane
- inner membrane: has cristaes (convolutions) and high protein content that includes the proteins of electron transport chain
- matrix: area bounded by inner membrane, site of many reactions in cell respiration
Mitochondrial Matrix
The compartment of the mitochondrion enclosed by the inner membrane and containing enzymes and substrates for the Krebs cycle.
mitosis
division of the nucleus
mitosis
division of the nucleus
mitosis
division of the nucleus or chromosomes
mitosis
division of the nucleus or chromosomes
Mitosis
Second stage of Cell Cycle;The stage of the cell cycle during which the cell
s nucleus divides into two nuclei and one copy of the DNA is distributed into each daughter cell.
...
Mitosis
Second stage of Cell Cycle;The stage of the cell cycle during which the cell
s nucleus divides into two nuclei and one copy of the DNA is distributed into each daughter cell.
...
mitosis
the phase of the cell cycle during which the replicated genome is divided.
mitosis
the phase of the cell cycle during which the replicated genome is divided.
mitotic spindle
An assemblage of microtubules and associated proteins that is involved in the movements of chromosomes during mitosis.
mitotic spindle
An assemblage of microtubules and associated proteins that is involved in the movements of chromosomes during mitosis.
Monozygotic (identical) Twins
- result when a single zygote splits into two embryos
- if splitting occurs at the two-cell stage of development, embryos will have separate chorions and separate placentas
- if it occurs at blastula stage, embryos only have one chorionic sac and share a placenta (and probably amnion)
Movements across the cell membrane
a) simple diffusion
b) facilitated diffusion
c) active transport
d) endocytosis
e) exocytosis
Muscle Tissue
- has great contractile capability
- involved in body movement
- three types: skeletal, cardiac and smooth
Na+ gradient established by primary active transport of Na+
K+/ATPase /What is the driving force for secondary active transport?
Na
K/ATPase /transmembrane protein of all cells in the body that pumps 3 Na+ atoms out of cell and brings in 2 K+ atoms per ATP
NAD+
the oxidized form of NAD; an electron carrying molecule that functions in cellular respiration
NADH
the reduced form of NAD; an electron-carrying molecule that functions in cellular respiration
NADP⁺
- nicotinamide adenine dinucleotide phosphate
- the reduced form, NADPH, is found in plant cells only
NAD⁺
nicotinamide adenine dinuclotide
Nervous Tissue
- composed of specialized cells called neurons
- these neurons are involved in the perception, processing and storage of information concerning the internal and external environments
Net Reaction for Glycolysis
glucose + 2ADP + 2Pi + 2 NAD⁺

-->

2 pyruvate + 2ATP + 2NADH + 2H⁺ + 2H₂O
Net reaction of Citric Acid Cycle per glucose molecule
2 Acetyl CoA + 6 NAD⁺ + 2 FAD + 2 ATP + 2Pi + 4H₂O

-->

4 CO₂ + 6 NADH + 2 FADH₂ + 2 ATP + 4 H⁺ + 2 CoA
Net reaction of photosynthesis
6CO₂ + 2H₂O + energy --> C₆H₁₂O₆ + 6O₂
Nitrogen Bases
Molecules that contain the element nitrogen along with other elements which pair up and connect to form the "rungs" of the DNA molecule.
Nitrogen Bases
Molecules that contain the element nitrogen along with other elements which pair up and connect to form the "rungs" of the DNA molecule.
Noncompetitive Inhibitors
- substance that forms strong covalent bonds with an enzyme
- may not be displaced by the addition of excess substrate
- irreversible
- noncompetitive inhibitor may be bonded at, near or remote from the active site
- can be overcome by increasing the concentration of the enzyme
nuclear envelope
the double lipid bilayer that surrounds the DNA in eukaryotic cells
nuclear envelope
the double lipid bilayer that surrounds the DNA in eukaryotic cells
nuclear envelope breaks down, mitotic spindle forms, and chromosomes condense
3 occurrences of prophase
nuclear localization sequence
a sequence of amino acids that directs a protein to the nuclear envelope, where it is imported by a specific transport mechanism.
nuclear localization sequence
a sequence of amino acids that directs a protein to the nuclear envelope, where it is imported by a specific transport mechanism.
nuclear matrix
The nuclear skeleton, a shape-maintaining protein
nuclear matrix
The nuclear skeleton, a shape-maintaining protein
nuclear membrane
membrane around the nucleus
nuclear membrane
membrane around the nucleus
Nuclear membrane
thin structure that surrounds and protects the nucleus
Nuclear pores
Dispersed in nuclear membrane, allow 2-way exchange of materials
nuclear pores
protein channels in the nuclear envelope that allow the free passage of small molecules.
nuclear pores
protein channels in the nuclear envelope that allow the free passage of small molecules.
Nuclear pores
structures in the nuclear envelope that allow passage of certain materials between the cell nucleus and the cytoplasm
Nucleoid
- in prokayrotes
- where the genetic material is concentrated as a single molecule of DNA
Nucleoid
The region in prokaryotic cells where the chromosome is located.
nucleoid region
area of prokaryotic cells where the DNA is concentrated.
Nucleolus
A dense structure in the nucleus where rRNA synthesis occurs
nucleolus
a region within the nucleus where rRNA is transcribed and ribosomes are partially assembled.
nucleolus
a region within the nucleus where rRNA is transcribed and ribosomes are partially assembled.
nucleolus
region of nucleus that produces ribosomes (rRNA) and house RNA polymerase I
Nucleolus
The organelle where ribosomes are made, synthesized and partially assembled, located in the nucleus
Nucleotide
A nitrogen base bonded to a deoxyribose and a phosphate molecule.
Nucleotide
A nitrogen base bonded to a deoxyribose and a phosphate molecule.
nucleus
control center of a cell
nucleus
control center of a cell
Nucleus
Double membrane bound DNA-containing organelle
nucleus
organelle that contains DNA and is site of transcription surrounded by nuclear envelope
obligate intracellular parasite"
- viruses can only reproduce in a living host cell
- lack structures for independent activity & reproduction
- virus attaches itself to a host cell, injects its nucleic acid, take control of protein synthesis within the cell
- viral genome replicates itself, produce protein coats and assembles new virions that leave host cells
- antiviral meds work by interfering with enzymatic reactions involved in viral replication. it
s easier to vaccinate to combat viruses
...
Obligate Intracellular Parasites
Organisms that require a host cell to express their genes and reproduce.
oncogenes
mutated genes that induce cancer
Oogenesis
- production of female gametes
- occurs in the ovarian follicles
- one primary oocyte completes meiosis I per month after menarche
- yields two secondary oocyte and a polar body
- secondary oocyte is expelled from the follicle during ovulation
- meiosis II doesn
t occur till fertilization
...
organ
a group of tissues that work together to do a special job
organ
a group of tissues that work together to do a special job
organ system
group of organs that work together
organ system
group of organs that work together
Organelle
A tiny structure in the cell that caries out a specific funtion for the cell that helps the cell work properly.
Organelle
A tiny structure in the cell that caries out a specific funtion for the cell that helps the cell work properly.
organelle
small structure in a cell that carries out specific cell functions
organelles
small structures in the cytoplasm that do special jobs
organelles
small structures in the cytoplasm that do special jobs
Osmosis
- simple diffusion of water from a region of lower solute concentration to a region of a higher solute concentration
- if membrane is impermeable to a particular solute, water will flow across membrane until solute concentration differences are equal
- types of molecules transported: H₂O
Osmosis
Diffusion of water - Passive movement of water from a region of higher water concentration to a region of lower water concentration.
osmosis
movement of water across a semipermeable membrane from area of low solute concentration of to area of high solute concentration
osmosis
movement of water through a membrane
osmosis
movement of water through a membrane
osmosis
the movement of water from its region of high concentration to its region of low concentration.
osmosis
the movement of water from its region of high concentration to its region of low concentration.
Ovaries
- female gonads
- found in the abdominal cavity
- produce eggs (ova)
- secrete esterogen and progesterone
- consist of thousands of follicles
Ovulation and Menopause
- women ovulate about once every four weeks
- menapause occurs between age 45 and 50
- during menopause, ovaries become less sensitive to the hormones that stimulate follicle development (FSH and LH), and eventually they atrophy
- remaining follicles disappear, estrogen and progesterone levels greatly decline and ovulation stops
Oxidation
- loss of an electron
- NAD⁺, FAD, NADP⁺ are referred to as oxidizing agents because they cause other molecules to lose electrons and undergo oxidation (while they
re reduced NADH, FADH₂, NADPH)
...
Oxidative Phosphorylation
- ATP is produced when high energy potential electrons are transferred from NADH and FADH₂ to oxygen by a series of carrier molecules located in the inner mitochondrial membrane
- as the electrons are transferred from carrier to carrier, free energy is released
- later this energy is used to form ATP
Oxidative Phosphorylation
The production of ATP using energy derived from the redox reactions of an electron transport chain.
oxygen, carbon dioxide, and small lipids
3 main items that move via simple diffusion
Parthenogenesis
- development of an unfertilized egg into an adult organism
- occurs naturally in certain lower organisms (bees and ants, some salamander)
- eggs of some organisms can be induced to develop parthenogenetically (not done naturally)
- since the organism develops from a haploid cell, all of its cells will be haploid
passive transport
thermodynamically favorable movement of solute across a membrane; movement of solute down a concentration gradient w/ no energy required
Pathway of Sperm
SEVEN UP:
Seminiferous tubules
Epididymus
Vas deferens
Ejaculatory duct
(Nothing)
Urethra
Penis
peripheral membrane protein
a protein that is associated with the plasma membrane of a cell, but is not embedded in the lipid bilayer.
peripheral membrane protein
a protein that is associated with the plasma membrane of a cell, but is not embedded in the lipid bilayer.
peripheral proteins
proteins not embedded in the plasma membrane that are stuck to integral proteins by H-bonding and hydrostatic interactions
Peroxisomes
- a type of microbodies
- contain oxidative enzymes that produce hydrogen peroxide by the transfer of hydrogen from a substrate to oxygen
- break fats down into smaller molecules that can be used for fuel
- smaller fat molecules also used in the liver to detoxify compounds harmful to the body (ex: alcohol)
Peroxisomes
Can produce hydrogen peroxide, break down fats, or detoxify compounds in the liver
Peroxisomes
Microbody responsible for the creation of hydrogen peroxide that is used to break down fats. Catalyzes detoxification reactions in liver.
peroxisomes
organelles that metabolize lipids and toxins w/ hydrogen peroxide
peroxisomes
small organelles that contain hydrogen peroxide produced as a byproduct of lipid metabolism. they convert peroxide to water and oxygen through enzyme catalase.
peroxisomes
small organelles that contain hydrogen peroxide produced as a byproduct of lipid metabolism. they convert peroxide to water and oxygen through enzyme catalase.
pH and electrical potential gradients
What kind of gradients are generated by pumping H+ into the intramembranous space?
phagocytosis
cell eating.
phagocytosis
cell eating.
Phagocytosis
engulfing of large particles
Phagocytosis
process in which phagocytes engulf and digest microorganisms and cellular debris
Phagocytosis
The process by which the cell intakes large particles, forming vesicles
Phase Contrast Microscope
- a type of light microscope
- allows study of living cells
- differences in refractive index are used to produce contrast between cellular structures
-this technique doesn
t kill the specimen
...
Phosphate
Molecules of a chemical that help make up the sides of the DNA molecule;alternates on the sides with deoxyribose.
Phosphate
Molecules of a chemical that help make up the sides of the DNA molecule;alternates on the sides with deoxyribose.
phospholipid
any of various compounds composed of fatty acids and phosphoric acid and a nitrogenous base, A molecule that is a constituent of the inner bilayer of biological membranes, having a polar, hydrophilic head and a nonpolar, hydrophobic tail. Are also built from a glycerol backbone.
Phospholipid
Consists of a hydrophobic and hydrophilic region; makes up the cell membrane
phospholipid
the primary membrane lipid, which consists of a glycerol molecule esterified to two fatty acid chains and a phosphate molecule.
phospholipid
the primary membrane lipid, which consists of a glycerol molecule esterified to two fatty acid chains and a phosphate molecule.
Phospholipid bilayer
a double layer of phospholipids that makes up plasma and organelle membranes
phospholipid bilayer
Has both a hydrophilic (polar) phosphoric acid and a hydrophobic (non-polar) fatty acid region. Hydrophilic regions are found on the outside of the membrane and hydrophobic regions are found on the interiorof the membrane. Structure allows for selective permeability.
phospholipids, proteins, and cholesterol
3 components of the plasma membrane
photosynthesis
plant makes its own food from light energy
photosynthesis
plant makes its own food from light energy
phygocytosis
the non-specific uptake of solid material by a cell accomplished by engulfing the particle with plasma membrane and drawing it into the cell.
phygocytosis
the non-specific uptake of solid material by a cell accomplished by engulfing the particle with plasma membrane and drawing it into the cell.
Pinocytosis
ingestion of fluids or small particles
Pinocytosis
process by which certain cells can engulf and incorporate droplets of fluid
pinocytosis
the non-specific uptake of liquid particles into a cell by invagination of the plasma membrane and subsequent "pinching off" of a small bit of the extracellular fluid.
pinocytosis
the non-specific uptake of liquid particles into a cell by invagination of the plasma membrane and subsequent "pinching off" of a small bit of the extracellular fluid.
Pinocytosis
The process by which small vesicles are formed to intake small molecules and fluid
Plasmids
- in prokayrotes
- smaller rings of DNA, consisting of just a few genes, replicate independently from main chromosome, often contain genes to survive adverse conditions
plasmids
small rings of DNA consisting of a few genes. They replicate independently of the main chromosome and often contain genes that allow the cell to survive adverse conditions
Plasmids
Small rings of DNA found naturally in some bacterial cells in addition to the main bacterial chromosome.
ploidy
number of sets of chromosomes
pore
a pathway through a plasma membrane that restricts passage based only on the size of the molecule.
pore
a pathway through a plasma membrane that restricts passage based only on the size of the molecule.
pores
tube structure in membrane that is nonselective, and only specific according to size
potassium leak channel
an ion channel specific for potassium found in the plasma membrane of all cells in the body.
potassium leak channel
an ion channel specific for potassium found in the plasma membrane of all cells in the body.
primary active transport
active transport that relies directly on the hydrolysis of ATP.
primary active transport
active transport that relies directly on the hydrolysis of ATP.
primary active transport
direct use of ATP hydrolysis to transport a molecule
Primary Oocyte
- immature ova
- diploid cells that form by mitosis in the ovary
- at birth, all of the primary oocyte that a female will produce during her lifetime are already in her ovaries
primary structure
The first level of protein structure; the specific sequence of amino acids making up a polypeptide chain. Once this is formed the single cahin can twist into the alpha helix or lie along itself and form a B-pleated sheet.
Prokaryotes
- unicellular organisms with a simple cell structure
ex: bacteria and cyanobacteria (blue-green algae)
- have an outer cell membrane but do not contain any membrane-bound organelles
- have a cell wall, cell membrane, cytoplasm, ribosomes (30S & 50S) & flagella
- have no true nucleus
Prokaryotes
Cell lacking a nuclear membrane and membrane-bound organelles, such as a bacterium.
prokaryotes
include bacteria and cyanobacteria, are unicellular organisms with simple cell structure. Have an outermembrane but do not contain membrane bound organelles. There is no true nucleus and the genetic material consists of a single circular molecule of DNA concentrated in the nucleoid.
proline
causes bends/kinks in the protein, ring structured R group, linking carboxylic acid to amine group.
Prophase
- chromosomes condense
- centriole pairs separate and move toward opposite poles of cell
- spindle apparatus form
- nuclear membrane dissolves
- kinetochores, attached kinetochore fibers, appear at the chromosome centromere
prophase
first and longest phase of mitosis, during which the chromosomes become visible and the centrioles separate and take up positions on the opposite sides of the nucleus
prophase
first and longest phase of mitosis, during which the chromosomes become visible and the centrioles separate and take up positions on the opposite sides of the nucleus
prophase
first phase of mitosis
prophase
first phase of mitosis in which chromosomes become visible and nuclear membraine disappears
prophase
first phase of mitosis in which chromosomes become visible and nuclear membraine disappears
Prophase
First phase of Mitosis;Chromosomes form, Centrioles go to opposite ends of cell, Spindle Fibers form a bridge across cell, and Nuclear Envelope disappears.
Prophase
First phase of Mitosis;Chromosomes form, Centrioles go to opposite ends of cell, Spindle Fibers form a bridge across cell, and Nuclear Envelope disappears.
prophase
the first phase of mitosis; replicated chromosomes condense, the spindle is formed, and the nuclear envelope breaks apart into vesicles.
prophase
the first phase of mitosis; replicated chromosomes condense, the spindle is formed, and the nuclear envelope breaks apart into vesicles.
Prophase I
- homologous chromosomes come together and intertwine
- at this stage, chromosome consists of two sister chromatids
- where recombination and crossing over happens, responsible for increased genetic diversity
Prophase II
- centrioles migrate to opposite poles
- spindle apparatus forms
Prostaglandins
A group of bioactive, hormone-like chemicals derived from fatty acids that have a wide variety of biological effects including roles in inflammation, platelet aggregation, vascular smooth muscle dilation and constriction, cell growth, protection of from acid in the stomach, and many more.
protein
any of a large group of nitrogenous organic compounds that are essential constituents of living cells. Built from a chain of amino acids linked polypeptide bonds.
protein can rotate on an axis and show lateral rotation, BUT CANNOT flip-flop
Describe the movement of proteins in the plasma membrane?
Proteins
- the body degrades amino acids only when there isn
t enough carbs available
- most amino acids undergo a transamination reaction where they lose an amino group to form an alpha-keto acid
- carbon atoms of most amino acids are converted into acetyl CoA, pyruvate or one of the intermediates of the citric acid cycle
...
Proteins that make up cytoskeleton
Actin filaments, intermediate filaments, microtubules
proteoglycan
Protein consisting of a small core protein with many carbohydrate chains attached, which can further attach to a long pollysaccharide (making a complex) are the major component of the extracellular matrix
Proton Gradient
- as NADH passes its electrons to the ETC, free H⁺ are released and accumulate in mitochondrial matrix
- ETC pumps these ions out of the matrix, across the inner mitochondrial membrane and into intermembrane space at each of the three protein complexes
- the continuous translocation of H⁺ creates a positively charged acidic environment in the intermembrane space
Proton-Motive Force
- from proton gradient
- drives H+ back across inner membrane and into the matrix
- membrane is impermeable to ions, so H⁺ must flow through specialized channels provided by enzyme complexes called ATP synthetases
- as H⁺ pass through ATP synthetases, energy is released to allow for the phosphorylation of ADP to ATP
- oxidative phosphorylation: coupling of oxidation of NADH with phosphorylation of ADP
pyruvate
Three-carbon compound that forms as an end product of glycolysis.
Pyruvate Decarboxylation
- pyruvate formed during glycolysis is transported from the cytoplasm into the mitochondrial matrix where it is carboxylated (lost a CO₂), and the remaining acetyl group is transfered to coenzyme A to form acetyl CoA.
- in process, NAD⁺ is reduced to NADH
- pyruvate + coenzyme A -- acetyl CoA
quarternary structure
Two or more polypeptide chains due to interactions of side chains involved in hydrophobic interactions, ionic bonds, hydrogen bonds, and disulfide bridges.can include non amino acid unit. Ex- Fe
receptor-mediated endocytosis
a highly specific cellular uptake mechanism, the molecule to be taken up must bind to a cell surface receptor found in a clathrin-coated pit.
receptor-mediated endocytosis
a highly specific cellular uptake mechanism, the molecule to be taken up must bind to a cell surface receptor found in a clathrin-coated pit.
receptors
complex proteins or glycoproteins embedded in the membrane with sites that bind to specific molecules in the cells external environment.
Receptors
Proteins/glycoproteins in the membrane that bind specific molecules outside the cell
Reduction
- gain of electrons
Regeneration
- the regrowth of a lost or injured body part
- replacement of cells occurs by mitosis
- ex: hydra and starfish
- in higher animals, regeneration is usually limited to the healing of tissues
- some internal organs (liver) can regenerate considerably as long as part of the organ remains viable
Regulation of Enzymatic Activity
done by:
- by allosteric effects
- inhibitory interactions
Regulators
- molecules other than substrate that bind to the enzme
- two types: allosteric inhibitors and allosteric activators
- inhibitor prevents an enzyme from binding to its substrate by stabilizing the inactive configuration
- activator stabilizes the active configuration, promoting formation of enzyme-substrate complexes, increases affinity of an enzyme for its substrate
Replication
Process that DNA goes through to make an exact copy of itself in the nucleus;Happens during Interphase
Replication
Process that DNA goes through to make an exact copy of itself in the nucleus;Happens during Interphase
Reproduction
- a process by which an organism perpetuates itself and its species
- divided into: cell division, asexual reproduction and sexual reproduction
resting membrane potential
an electrical potential established across the plasma membrane of all cells by the NA/K-ATPase and the K leak channels.
resting membrane potential
an electrical potential established across the plasma membrane of all cells by the NA/K-ATPase and the K leak channels.
Review of Glucose Catabolism
- Net amount of ATP = ATP by substrate level phosphorylation + ATP by oxidative phosphorylation
- Substrate level = 1 glucose = ATP from glycolysis + (1 ATP x 2 turn of Citric Acid Cycle) ---> 4 ATP
- Oxidative = 32 ATP
- Total = 36 ATP
Ribosome
small particle in the cell on which proteins are assembled; made of RNA and protein
Ribosomes
- sites of protein production
- synthesized by nucleolus
- two subunits: one large and one small
- each subunit is composed of rRNA and proteins
- free ribosomes: found in cytoplasm
- bound ribosomes: line the outer membrane of endoplasmic reticulum
Ribosomes
Sites of protein production
ribosomes
small round structures that make proteins
ribosomes
small round structures that make proteins
ribosomes
structures that function to synthesize proteins; perform translation
Rosalind Franklin
In 1952, first to use X-Rays to photograph the DNA molecule.
Rosalind Franklin
In 1952, first to use X-Rays to photograph the DNA molecule.
Rough Endoplasmic Reticulum
a region that is recognized by the grainy appearance of the ribosomes on their outer surface, where the cell
s proteins are made
...
rough ER
a large system of folded membranes within a eukaryotic cell that has ribosomes bound to it.
rough ER
a large system of folded membranes within a eukaryotic cell that has ribosomes bound to it.
Rough ER
ER with ribosomes on the outside, involved in protein synthesis
rough ER
organelle that synthesize and modify secretory, membrane bound, and organelle proteins
S phase
stage of interphase in which DNA is replicated
S phase
stage of interphase in which DNA is replicated
S phase
synthesis; when the cell actively replicates its genome.
S phase
synthesis; when the cell actively replicates its genome.
S Stage (synthesis)
- each chromosome is replicated so that during division, a complete copy can be distributed to each daughter cell
- two identical sister chromatids held together at a region called the "centromere"
- telomeres: ends of the chromosomes
- 2 x 2N number of chromosomes
s-phase
synthesis phase of cell cycle where cell actively replicates its genome
saturated fatty acids
A fatty acid in which all carbons in the hydrocarbon tail are connected by single bonds, thus maximizing the number of hydrogen atoms that can attach to the carbon skeleton.
Saturation Point
where all available active sites on an enzyme complex are occupied by substrate molecules
second messenger system
process that occurs due to binding of ligand to receptor protein that activates an enzyme cascade. The response is quick due to amplification, and usually does not last long
secondary active transport
active transport that relies on an established concentration gradient, typically set up by a primary active transporter. Relies on ATP indirectly.
secondary active transport
active transport that relies on an established concentration gradient, typically set up by a primary active transporter. Relies on ATP indirectly.
secondary active transport
the indirect use of ATP hydrolysis, that creates a gradient for another molecule
secondary structure
Alpha helix and beta pleated sheet formed through formation of hydrogen bonds., The second level of protein structure; the regular local patterns of coils or folds of a polypeptide chain.
secreted protein, transmembrane protein, lysosomal protein
3 proteins that will finish translation in the rough ER
Secretory vesicles
Produced by Golgi, release contents to cell
s exterior
...
Semiautonomous
An organelle containing its own DNA and ribosomes within a eukaryotic cell
Seminal Fluid
- mixed with sperm, aids in sperm transport by lubricating passageways
- semen: sperm + seminal fluid
- produced by:
a) seminal vesicles: fructose-rich fluid, serves as energy source
b) prostate gland: alkaline milky fluid to protect from acidic environment in female
s reproductive tract
c) bulbourethral glands: small amount of viscous fluid, function unknown
...
Sexual Reproduction
- fusion of two gametes (specialized sex cells produced by each parent)
- meiosis is the process where the sex cells are produced
- mitosis preserves the diploid chromosome number while meiosis halves it
- somatic cells undergo mitosis, gametocytes undergo meiosis
- during fertilization, two haploid gametes fuse, restoring the diploid number
sexual reproduction
process by which cells from two different parents unite to produce the first cell of a new organism
sexual reproduction
process by which cells from two different parents unite to produce the first cell of a new organism
side chain
Another term for R-group; variable grp of an amino acid that differs w/ each and determines the unique characteristics of a particular amino acid. also attached to the alpha carbon.
signal recognition particle
a cytoplasmic protein that recognizes the signal sequences of proteins destined to be translated at the rough ER.
signal recognition particle
a cytoplasmic protein that recognizes the signal sequences of proteins destined to be translated at the rough ER.
signal sequence
a short sequence of amino acids, usually found a the N-terminus of a protein being translated, that directs the ribosome and mRNA to the membranes of the rough ER where translation will be completed.
signal sequence
a short sequence of amino acids, usually found a the N-terminus of a protein being translated, that directs the ribosome and mRNA to the membranes of the rough ER where translation will be completed.
signal sequence
N-terminus sequence on protein that determines whether protein will finish translation in the rough ER; it is recognized by a signal recognition particle on the ribosome
signal transduction
the intracellular process triggered by the binding of a ligand to its receptor on the cell surface.
signal transduction
the intracellular process triggered by the binding of a ligand to its receptor on the cell surface.
Simple Diffusion
- net movement of dissolved particles down their concentration gradients
- from high concentration to low
- passive process
- types of molecules transported: small/non polar (O₂, CO2, etc)
simple diffusion
diffusion of solute through the membrane w/o a protein
Simple Diffusion
Passive movement of particles from a region of high concentration to a region of low concentration without the use of energy.
sister chromatids
identical copies of a chromosome attached to each other at a centromere
sister chromatids line up along the metaphase plate
What occurs in metaphase?
Smooth Endoplasmic Reticulum
An endomembrane system where lipids are synthesized, calcium levels are regulated, and toxic substances are broken down.
smooth ER
a network of membranes inside eukaryotic cells involved in lipid synthesis, detoxification, and/or calcium storage.
smooth ER
a network of membranes inside eukaryotic cells involved in lipid synthesis, detoxification, and/or calcium storage.
Smooth ER
ER without ribosomes on it, involved in lipid synthesis and detoxification
smooth ER
organelle that perform detoxification, glycogen breakdown, and steroid synthesis in a cell
SOD and catalase
What two enzymes do peroxisomes possess to breakdown hydrogen peroxide and superoxidative species?
solvation
the process by which the positive and negative ions of an ionic solid become surrounded by solvent molecules
Somatic Cells
- or called autosomal cells
- everything but the gamete
- contain diploid number of chromosomes characteristic of its species (2N)
- N is the number of chromosomes found in haploid cell (gamete)
- in human, 2N = 46 and N = 23
Spermatogenesis
- "sperm production"
- occurs in seminiferous tubules
- after a male reaches sexual maturity, about 3 million primary spermatocytes begin spermatogenesis per day
- maturation takes about 65-75 days
Spermatogenesis Process
- spermatogonia (diploid) differentiate into primary spermatocytes (diploid)
- primary spermatocytes undergo the first meiotic division and yield two secondary spermatocytes (haploid)
- secondary spermatocytes undergo second meiotic division and yield four spermatids (haploid)
- spermatogonia (2N) --> 1° spermatocytes (2N) --> meiosis I --> 2° spermatocytes (N) --> spermatids (N) --> spermatozoa (N)
Spermatozoa
- spermatids after a series of changes, becomes a mature sperm
- mature sperm is an elongated cell with a head, neck, body and tail
- head consists almost entirely of the nucleus
- tail (flagellum) propels the sperm
- mitochondria in the neck and body provide energy for locomotion
spindle
microtubule structure that separates chromosomes during mitosis
spindle
microtubule structure that separates chromosomes during mitosis
Spindle Fibers
Small thin tubes, made during Interphase, that attach to chromosomes and move them around during mitosis.
Spindle Fibers
Small thin tubes, made during Interphase, that attach to chromosomes and move them around during mitosis.
spindles shorten and centromeres of each sister chromatid are pulled apart. Also, a cleavage furrow begins to form
What occurs during anaphase?
Stages of Mitosis
PMAT:
a) Prophase
b) Metaphase
c) Anaphase
d) Telophase
steroids
A type of lipid characterized by a carbon skeleton consisting of four rings with various functional groups attached.
structural protein
very important in binding structures together and providing strength in certain body tissues, Keratins, collagens, and cytoskeleton, Proteins that are important for holding cells and organisms together, such as the proteins that make up the cell membrane, muscles, tendons, and blood
Substrate
- the molecule upon which an enzyme acts
Substrate Level Phosphorylation
- ATP synthesis is directly coupled with the degradation of glucose without the participation of an intermediate molecule like NAD⁺
Synapsis
homologous chromosomes come together and intertwine
telomerase
enzyme that helps maintain the end of chromosomes after replication; has RNA that acts as a reverse transcriptase
telomere
a specialized region at the ends of eukaryotic chromosomes that contains several repeats of a particular DNA sequence.
telomere
a specialized region at the ends of eukaryotic chromosomes that contains several repeats of a particular DNA sequence.
telomere
structure at the end of a chromosome with a large number of repeats
Telophase
- spindle apparatus disappears
- new nuclear membrane forms around each set of chromosomes
- nucleoli reappears
- chromosomes uncoil
- cytokinesis occurs
Telophase
Fourth phase of Mitosis; Chromosomes change back into Chromatin, new Nuclear Envelope forms around each set of Chromosomes; and cell membrane pinches inward.
Telophase
Fourth phase of Mitosis; Chromosomes change back into Chromatin, new Nuclear Envelope forms around each set of Chromosomes; and cell membrane pinches inward.
telophase
last phase of mitosis, chromosome are in two new cells and nuclear membranes start to reform
telophase
last phase of mitosis, chromosome are in two new cells and nuclear membranes start to reform
telophase
the final stage of mitosis during which a nuclear membrane forms around each set of new chromosomes
telophase
the final stage of mitosis during which a nuclear membrane forms around each set of new chromosomes
telophase
the fourth and final phase of mitosis;the nuclear envelope reforms, chromosomes decondense, and the mitotic spindle is disassembled.
telophase
the fourth and final phase of mitosis;the nuclear envelope reforms, chromosomes decondense, and the mitotic spindle is disassembled.
Telophase I
- a nuclear membrane forms around each new nucleus
- each chromosomes still consists of sister chromatids joined at the centromere
- cells divide into two daughter cells
- between cell divisions, there might be "interkinesis", a short rest period where chromosomes partically uncoil
Telophase II
- nuclear membrane forms around each new haploid nucleus
- two daughter cells are formed after cytokinesis
- by completion of meiosis II, four haploid daughter cells are produced per gametocyte
terpene
Organic compound whose carbon skeleton is composed of 2 or more 5-carbon isoprene structural units. It is formed by joining the tail of one isporene structural unit to the head of another. Includes Vitamin A.
tertiary structure
The third level of protein structure; the overall, three-dimensional shape of a polypeptide due to interactions of the R groups of the amino acids making up the chain.
Tetrad
chromosome consisting of two sister chromatids
The Cell Cycle
- four stages: G₁, S, G₂ and M
- interphase: first three stages
- mitosis includes the actual cell division
The Citric Acid Cyle (TCA Cycle)
- known as the Krebs cycle or the tricarboxylic acid cycle (TCA cycle)
- begins when the two carbon acetyl group from acetyl CoA combines with oxaloacetate, a four carbon molecule, to form the six carbon citrate
- 2CO₂ are released, oxaloacetate is regenerated to use for another turn of the cycle
- 1 cycle = 1 ATP produced by substrate level phosporylation via GTP intermediate
- electrons are transferred to NAD⁺ and FAD, generating NADH and FADH₂, which transport electrons to electron transport chain
The Citric Acid Cyle continued
- electrons are transferred to NAD⁺ and FAD, generating NADH and FADH₂, which transport electrons to electron transport chain, where ATP is produced via oxidative phosporylation
- each molecule of glucose = 2 pyruvates
2x3 NADH --> 6 NADH
2x1 FADH₂ --> 2 FADH₂
2x1 GTP (ATP) --> 2 ATP
The Induced Fit Hypothesis
- a model describing the formulation of an enzyme-substrate complex
- describes that the active site of an enzyme has some flexibility of shape
- when the appropriate substrate comes in contact with the active site, the active site will conform to fit the substrate
theory
idea that explains something and is supported by data
theory
idea that explains something and is supported by data
Thymine
A nitrogen base that makes up the "rungs" of the DNA ladder;Pairs with Adenine
Thymine
A nitrogen base that makes up the "rungs" of the DNA ladder;Pairs with Adenine
tight junctions
junctions that tightly bind cells to each other and prevent the free movement of items
tissue
group of cells that look alike and work together
tissue
group of cells that look alike and work together
Tissues
- groups of morphologically and functionally related cells
- types of tissues: epithelial, connective, nervous and muscle
transmembrane domain
the portion of an integral membrane protein that passes through the lipid bilayer.
transmembrane domain
the portion of an integral membrane protein that passes through the lipid bilayer.
transmembrane domains
hydrophobic amino acid residues that remain on protein after translation in rough ER of a protein that is destined to be an integral protein
transmembrane domains
the portion of an integral protein that passes through the lipid bilayer.
transmembrane domains
the portion of an integral protein that passes through the lipid bilayer.
Transport Proteins
A transmembrane protein that helps a certain substance or class of closely related substances to cross the membrane.
Transport proteins
Span the cell membrane and allow passing of certain ions and polar molecules
triacylglycerols
Storage lipids. Function is to store energy and can be fat in bodies of animals. Consists of glycerol molecule to 3 fatty acids attached to a three carbon backbone. May also function to provide thermal insulation and padding to an organism.
Tubulins
The primary component of microtubules
tumor
a mass of abnormal cells that develop when cancerous cells divide and grow uncontrollably
tumor
a mass of abnormal cells that develop when cancerous cells divide and grow uncontrollably
two daughter cells that are identical to each other and identical to the parent cell
What is the end product of mitosis?
Two types of cofactors
a) metal cations: Zn²⁺, Fe²⁺
b) "coenzymes"/small organic groups: biotin
- coenzymes can
t be syntheized by the body and are obtained from diet as vitamin derivatives
- lack of these vitamins can impair the enzyme
...
s activity and lead to disease
...
unsaturated fatty acids
A fatty acid possessing one or more double bonds between the carbons in the hydrocarbon tail. Such bonding reduces the number of hydrogen atoms attached to the carbon skeleton.
Uterus
- site of fetal development
vacuoles
liquid-filled spaces in the cytoplasm
vacuoles
liquid-filled spaces in the cytoplasm
Vaginal Canal
- site of sperm deposition during intercourse
- passageway through which a baby is expelled during childbirth
Vesicles
Pockets of cell wall/membrane material that fuse together down the center of a plant cell to form the cell plate
Vesicles
Pockets of cell wall/membrane material that fuse together down the center of a plant cell to form the cell plate
Vesicles and Vacuoles
- membrane-bound sacs involved in the transport and storage of materials that are ingested, secreted, processed or digested by the cell
- vacuoles are larger than vesicles and are more likely to be found in plant cells
Vesicles and Vacuoles
Membrane-bound sacs involve in the transport of materials into/out of cells
Virion
a fully developed viral particle
Viruses
- acellular structures composed of nucleic acid enclosed by a protein coat
- range in size from 20-300 nm (prokaryotes are 1-10 nm & eukaryotes are 10-100 nm)
- nucleic acid can be either linear or circular and has four varieties: single-stranded & double-stranded DNA, single-stranded and double-stranded RNA
Vulva
- external female genitalia
water, glucose, amino acids, and ions
4 main items that can be transported via facilitated diffusion
Watson and Crick
Scientists who figured out the structure of DNA.
Watson and Crick
Scientists who figured out the structure of DNA.
Works well for small hydrophobic molecules that move according to a gradient
...
Zona Pellucida
- inner layer of the oocyte cell membrane
Zymogen
- enzyme that is secreted in an inactive form
- cleaved under certain physiological condition to the active form of the enzyme
- examples: pepsinogen, typsinogen, chymotrypsinogen. cleaved in the digestive tract to yield the active enzymes pepsin, trypsin and chymotrypsin
amphipathic /molecule that has both a hydrophilic region and a hydrophobic region such as a phosopholipid