75 terms

WGU INC1 Module 9

Organisms
STUDY
PLAY

Terms in this set (...)

What are the characteristics of living things?
-use energy
-develop & grow
-maintain themselves
-can reproduce
-are part of evolving populations
chemical reaction
A process that produces one or more substances that are different from the original substance (like baking or burning)
What happens during a chemical reaction?
one or more new compounds are formed as a result of the rearrangement of atoms. Chemical equation is written to represent. Reactants = substances about to react. Products = newly formed substances
Why is the law of conservation of energy important in chemical reactions?
Law of conservation of energy states that atoms are neither created nor destroyed in a chemical reaction - they are just rearranged. Every atom present before a reaction must be present after the reaction - even though the groupings of atoms are different; ( the law of mass conservation states that a chemical equation must be balanced; meaning that each atom shown in the equation must appear on both sides the same # of times)
law of conservation of energy
Matter is not created nor destroyed in any chemical or physical change
What are factors that affect the reaction rate of chemical reactions?
concentration of reactants, temperature, the addition of a catalyst
concentration of reactants
reactions involving liquid or gases; as concentration of reactants increase, rate or reaction increases. (Example: 10 volume developer used in hair coloring versus 40 volume; water)
How does temperature affect the reaction rate of chemical reactions?
if they absorb heat or electromagnetic radiation it will make it go quicker; however some cold temperatures can slow down a reaction or stop it all together. (Example: Hair color lightens & develops quicker when heat is applied)
How does the addition of a catalyst affect the reaction rate of chemical reactions?
a substance that increases the rate of a chemical reaction by lowering its activation energy. The catalyst can be a reactant, but then regenerates as a product and is then available to catalyze subsequent reactions. (Example: Ammonia acts as a catalyst when permanent hair color comes together with peroxide; stain fighters; meat tenderizer; catalytic converter; water)
rate law
An equation that shows the dependence of the reaction rate on the concentration of each reactant
collision theory
For a reaction to occur the particles must collide and the colliding particles must have enough activation energy to react
acid
A substance that increases the hydrogen ion concentration of a solution. (donates an ion) (meaning: sour) (Examples: citrus fruits, vinegar, toilet bowl cleaners, carbonated beverages.)
base
A substance that decreases the hydrogen ion concentration in a solution. (accepts an ion) (Example: baking soda, ashes, soap, sodium hydroxide)
salt
A compound resulting from the formation of an ionic bond between an acid & a base.
How can the addition of sunlight affect chemical reactions?
It will change the temperature. (Example: If you go sit in the sunlight with hair bleach on your hair, your hair will develop faster, and may potentially be damaged; or photosynthesis)
How do enzymes speed up chemical reactions in cells?
They are large, complex proteins in cells of living organisms that act as a catalyst. It binds the reactants of a reaction & releases the products of the reaction. They are not altered or destroying in the reactions they catalyze - making them available for the same reaction over & over
photosynthesis
Conversion of light energy from the sun into chemical energy. (Example: energy is stored)
cellular respiration
A complex set of chemical reactions involving an energy transformation where potential chemical energy in the bonds of "food" molecules is released and partially captured in the bonds of adenosine triphosphate (ATP) molecules. (Example: stored energy is released)
prokaryotic cells "before nucleus"
Lacks nucleus. Been around longer - only living things on Earth for awhile. Lineages - bacteria & archaea. Single celled - very small. DNA is found in circular chromosome - not contained within a nucleus. Has outer cell wall to help protect
eukaryotic cells "true nucleus"
Has nucleus as well as other structures. Can be single celled or composed of many cells. DNA is contained in distinct nucleus. DNA is also in linear chromosome. Has numerous organelles (structures that perform specific functions in cell). Much larger than other type of cell.
ATP
adenosine triphosphate (it provides energy for cellular processes.)
B.A.A.D.
acronym used to memorize how acids & bases handle protons. (Stands for: Bases Accept, Acids Donate)
Unit used to measure energy?
joules
How do plant cells differ from animal cells?
plant cells- cell membranes, ridged cell wall, chloroplasts, large central vacuoles.

animal cells- cell membrane, no wall, no chloroplasts, no central vacuoles.
diffusion
Movement of molecules from an area of higher concentration to an area of lower concentration.
osmosis
Movement of WATER molecules from high to low, example of passive transport
facilitated diffusion
Another type of passive transport, used for molecules that cannot readily diffuse through cell membranes.
active transport
Energy-requiring movement of molecules across a membrane from a region of lower concentration to a region of higher concentration.
endocytosis
Active transport process where a cell engulfs materials with a portion of the cell's plasma membrane and releases the contents inside of the cell.
invagination
The folding of a small area of the plasma membrane into the interstitial fluid to form an outside pocket for endocytosis.
exocytosis
An active transport process by which materials are expelled from a cell
mitosis
(body cell division) A type of cell division that results in two daughter cells each the same as the parent nucleus, typical of ordinary tissue growth. (Occurs in all organisms, makes 2 daughter cells, makes everything other than sex cells, process of asexual reproduction)
asexual reproduction
A reproductive process that involves only one parent and produces offspring that are identical to the parent. (examples: include jellyfish, some bees, yeast, aphids, fish and sharks)
meiosis
(sex cell division), Cell division that produces reproductive cells in sexually reproducing organisms. (Occurs in humans, plants, animals and fungi, makes 4 daughter cells, creates either a male sperm or a female egg cell) # of chromosomes are reduced by half through the separation of chromosomes making a diploid cell.
metaphase
2nd phase of mitosis; Chromosomes align themselves along the center of the cells.
anaphase
3rd phase of mitosis; Centromeres divide
telophase
4th phase of mitosis, -Chromosomes become indistinc
prophase
1st phase of mitosis, Chromatin condenses into chromosomes
prophase I
1st phase of meiosis- homologous chromosomes come together and intertwin
metaphase I
2nd phase of meiosis- the paired homologous chromsomes (tetrads) align at the center of the cell (the metaphase plate).
anaphase I
3rd phase of meiosis I. the replicated homologous chromosomes are separated (the tetrad is split) and pulled to opposite sides of the cell.
telophase I
4th phase of meiosis- two cells; 2n of chromosome number.
metaphase II
2nd phase of meiosis II. Metaphase II is identical to mitotic metaphase, except that the number of chromosomes was reduced by half during meiosis I.
anaphase II
3rd phase of meiosis II. the sister chromatids are finally spearated at their centromeres and puled to opposite sides of teh cell. is identical to mitotic anaphase, excep the number of chromosmes was reduced by half during meiosis I.
telophase II
4th and final phase of meiosis II. Telophase II is identical to mitotic telophase, except that the number of chromosomes was reduced by half during meiosis.
Mendel's Laws
Two laws summarizing Gregor Mendel's theory of inheritance. The Law of Segregation states that each hereditary characteristic is controlled by two `factors' (now called alleles), which segregate and pass into separate germ cells. The Law of Independent Assortment states that pairs of `factors' segregate independently of each other when germ cells are formed.
genetic mutations
Changes in the genetic material of cells that passes from one generation to another.
Explain how crossing over in meiosis promotes genetic variation.
Crossing over occurs when the homologous chromosomes are lined up at the equatorial plane and one chromosome exchanges corresponding parts with its homologue. Causes the chromosomes of the dividing cell to no longer be identical to ones in the parent cell. Results in chromosomes being composites of the two homologous parent chromosomes. Results in recombination - production of new combination of genes different from those in parental chromosomes. Occurs at different points in meiotic division - produces lots of genetic variation
The principle of segregation (Mendel's Law)
states that each unit character separates into a different sex cell.
The principle of independent assortment (Mendel's Law)
states that genes for different traits can segregate independently during the formation of gametes
What causes genetic mutations?
occurs when the sequence of nucleotides (A,C,G,T sequence) in an organisms DNA is changed. Can be from errors during DNA replication or exposure to mutagens (mutation causing agents) ex - uv light, x-rays, chemicals. Ultimate source of all genetic variation and provide raw materials for evolution and natural selection; can be inherited, or acquired.
heredity mutations
gene mutations that occur in sex cells will be passed to the offspring
acquired mutations
what most cancers are, occurs when DNA in a cell changes during the person's life. This can be caused by environmental influences such as exposure to radiation or toxins.
Different types of mutations.
-substitution
-insertion
-deletion
-frame shift
substitution
Change to a chromosome as a result of a mutation in which a single nucleotide is substituted with (or exchanged for) a different nucleotide; such as switching A to G
Insertion
A mutation where one or more nucleotides are added to the base sequence
deletion
A mutation where one or more nucleotides are lost in the base sequence
frameshift
A mutation occurring when the number of nucleotides inserted or deleted is not a multiple of three, resulting in the improper grouping of the following nucleotides into codons.
How does ionizing radiation from radioactive materials damage the DNA?
when it strike electrons in the body with enough energy, electrons are freed from the atoms they were orbiting. Free electrons then strike & damage DNA directly. More frequently - damage occurs indirectly when freed electron hits water molecule in a cell producing free radicals (group of atoms that has an unpaired electron and is consequently unstable & highly reactive). Free radicals react with wide variety of molecules in body - including DNA. Interactions with DNA damage it, causing 1 or more genetic mutations. Frequently dividing cells are more vulnerable to radiation damage
point mutation
A change in a gene at a single nucleotide pair.
Why are bone marrow cells and cells in the gastrointestinal tract more vulnerable to radiation damage?
because of the water that makes up most of the cells volume is affected and carried throughout the whole body.
Why do ultraviolet radiation and radon cause cancer?
radon- because it's a radioactive gas that is released in rocks & soil. Radioactive particles from radon can damage cells that line the lungs & lead to lung cancer. Radon is the 2nd leading cause of lung cancer in the USA.
ultraviolet- from the sun/sun exposure. The melanin absorbs the dangerous UV rays that cause cancer; leads to breaks in the strand of DNA.
cells
Basic unit of life
DNA
A double-stranded, helical nucleic acid molecule capable of replicating and determining the inherited structure of a cell's proteins.
RNA
A type of nucleic acid consisting of nucleotide monomers with a ribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and uracil (U); usually single-stranded; functions in protein synthesis and as the genome of some viruses; resembles DNA but it's single stranded and uses a different sugar molecule and nitrogenous base- uracil instead of thymine.
Describe how cells, tissues, organs and organ systems work together to perform human body functions.
All part of living things & all living things use energy. Our hearts continue to pump; our blood carries oxygen and nutrients to tissues and kidneys filter waste. Cells make up tissue (group of similar cells that performs a certain function). Multiple tissues combine to make an organ (structure in body that has certain function). Multiple organs make up an organ system responsible for performing particular bodily functions
How does our body maintain homeostatis?
through all of it's functioning. (Example: breathing, eating, and excreting)
Explain how the neurons, spinal cord, and brain work together to respond to stimuli.
neurons receive impulses and carry them from the sense organs to the spinal cord, or brain.
Explain the functions of the cells, heart, arteries, and veins of the circulatory system in transporting oxygen and carbon dioxide throughout the body. (circulatory system)
red blood cells transport oxygen from the lungs to the cells of the body through the blood stream. The arteries of the heart pump the oxygen rich blood away from heart to tissues/organs like the brain. The arteries get smaller the further away from the heart that they are and are then called veins, veins are what bring the "used" blood back to your heart.
Describe how the cells, tissues, and organs associated with the digestive system break down food.
glands release gastric juices (a high acid mix- digestive enzymes and a protective mucous that prevents the stomach from digesting its own tissues.) Digestive enzymes and muscles combine to reduce our food to a liquid called chyme. Chyme exits stomach into small intestine where digestion continues then the body absorbs the nutrients from the food, after that it moves to the large intestine where water & sodium are absorbed. From there feces are eliminated.
Explain how the cells, tissues and organs in the respiratory and circulatory system function interdependently to provide cells with oxygen.
respiratory system gets oxygen into the circulatory system that takes the oxygen through the blood stream to other parts of the body.
Urinary System
Composed of kidneys, ureters, urinary bladder, and urethra. Eliminates nitrogenous wastes from the body. Regulates water, electrolyte, and pH balance of the blood.
Explain the role of cells, tissue and organs in the acquired immune response.
causes tissues to swell and turn red if you cut your finger or scrape your knee. When tissue is damaged it releases a chemical called histamine, those increase blood flow to the site and cause local capillaries to leak fluid. That fluid causes swelling, which helps to isolate the injury from other body tissues. Histamines also attract cells to the wound to help it heal. Sometimes that battle produces pus. Pus is dead bacteria, tissue and dead/living innate immune system cells.
List of DNA base pairs
Adenine & Thymine (pairing)
Guanine & Cytosine (pairing)

T & A go together (pairing)
G & C go together (pairing)

Sample
A->T
C->G
C->G
G->C
T->A
List of RNA base pairs
Adenine & Uracil (pairing)
Guanine & Cytosine (pairing)

A & U go together
G & C go together

Sample
U -> A
G -> C
A -> U
A -> U
C -> G