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AP BIO 12 13 14
mreh^5
80
Biology
12th Grade
11/29/2011

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Term
DNA (what it is, how many pairs of nucleotides, chromatin vs. chromosome)
Definition
long thin molecule that stores genetic information / humans have more than 6 billion pairs / chromatin is unravelled DNA in eukaryotic cell's nuclei between cell divisions and during cell division it is coiled into very compact structures called chromosomes
Term
chromosomes (what they are, what's required to form them)
Definition
rod shaped structures made of a single DNA molecule and proteins / many levels of DNA coiling are required to form a chromosome
Term
how chromatin coils into chromosomes using histones and non-histone proteins
Definition
DNa in eukaryotic cells wraps tightly around proteins called histones that help maintain the shape of the chromosome and aid in the tight packing of DNA (non-histone proteins involved in controlling activity of specific regions of the DNA)
Term
histone vs. nucleosome vs. chromatid vs. centromere
Definition
proteins respomsible for the first level of DNa packaging vs. unfolded chromatin that looks like beads on a string in which DNA winds around a core of histone proteins vs. each identical half of chromosome vs. constricted area that holds chromatids together
Term
prokaryotic chromosome structure
Definition
DNA is made up of one circular chromosome consisting of a circular DNA molecule and associated proteins, that is attached to the inside of cell membrane
Term
chromosome numbers
Definition
each species has a characteristic number of chromosomes (fruit flies have 8 chromosomes, potatoes+plums+chimps have 48)
Term
sex chromosomes vs. autosomes
Definition
determine sex (X or Y) x, may carry genes for other characteristics vs. all other 44 chromosomes, where in each cell theres two copies of each, one from mommy and one from daddy (homologues) that are the same size and shape and carry the same genes for the same traints (like eye color)
Term
karyotype (and 3 steps)
Definition
photomicrograph of the chromosomes in a dividing cell (46 chromosomes, 22 homologous pairs and 2 sex chromosomes) that displays chromosomes from biggest to smallest prepared by:
1. isolating somatic cells
2. growing them in a culture till metaphase
3. staining and viewing
Term
reason for karyotype (to see genetic abnomalities) where most occur, what type they are and how they effect baby, most common and well known autosomal abonormality
Definition
most occur on autosomes / they are monosomies or trisomies that cause fetus to die before birth or have multiple physical malformatinos, mental retardation, and relatively short lives / DOWN SYNDROME
Term
diploid vs. haploid
Definition
2n, two sets of chromosomes, both for each homologous pair, 2 sex chromosomes, all normal human cells except reproductive ones vs. n, one set of chromosomes, one for each homologous pair, 1 sex chromosomies, sperm and eggs, half the number of cells present in diploid cells...wtf that means
Term
cell division (what it is, what happens before and after)
Definition
the process by which a cell divides into two new daughter cells (before every cell must copy its genetic information, after each daughter cell gets a complete compy of that information)
Term
steps of binary fission (fast, easy process!)
Definition
1. chromosome attached to inside of cell makes a copy of itself, results in to identical chromosomes
2. cell grows and enlarges to 2x normal size and cell wall begins to form between 2 cgromosomes
3. cell splits into two identical cells
Term
mitosis vs. meisosis
Definition
makes new cells that are genetically identical to original cell and occurs in reproduction of unicellular organisms (asexual) vs. reduces the chromosome number by half where new cells join together later in life to form 2n
Term
Cell cycle / interphase / mitosis
Definition
repeating set of events that makes up the life cycle of a cell (G1, S, G2, M, C) / everything but PMAT/C - 90% of cell cycle consisting of G1 (growth) S(synthesis of DNA) and G2 (preparation for cell division) / mitosis = nuclear division, cytokinesis = cytoplasm division (mitosis PMAT and does NOT incude interphase)
Term
G1 phase (restriction point)
Definition
cells grow to mature size, no proteins and organelles are synthesized, and is the gap following cell division and preceding DNA replication
restriction point: CDK (cyclin dependent kinase) is activated by binding to cyclin that phosphorylates proteins which sends cell into S phase
Term
S phase
Definition
chromosomes are replicated, DNA is copied (DNA synthesis) and once a cell enters this phase it usually copmletes the rest of the cycle so it's not left with duplicated chromosomes
Term
G2 phase(MPF)
Definition
shortest of 3 interphase phases, cell prepares for cell division by producing many of the organeelles and molecules required for cell division and once G2 is completed, ecll is ready to enter the M phase and begin the process of division
MPF: a CDK compex that affects cyclin fluctuations and also triggers the cells passage past the G2 checkpoint into M phase
Term
G0 phase
Definition
cells excit the cell cycle (usually from G1), they do not copy their DNA or prepare for division (example = fully developed cells in CNS like nerve cells)
Term
prophase (prometaphase) (5 things)
Definition
-1st and longest stage (50-60%)
-DNA coils into rod shaped chromosomes, which consist of two identical chromatids connected by centromere
-nucleus and nuclear membrane start to break down and disappear
-centrosomes appear and release centrioles in a pair of small, cylindrical bodies (only in animals) and they also move towards the oposite poles of the cell
-spindle fibers (microtubles) radiate from centrosomes
different types of fibers:
mitotic spindle: array of fibers to divide the chromatids equally
kinetochore fibers: attach to disc shaped protein called kinetochore found in centromere of each chromosome and extend from these proteins to chromosomes
polar fibers: extend from centrosome to centrosome
Term
metaphase (3 things)
Definition
-easier phase to identify under microscope
-karyotype usually made from photomicrographs of chromosomes in this phase
-kinetochore fibers move chromosomes to the center of dividing cell and once there, hold them in place
Term
anaphase (3 things)
Definition
-chromatids separate and move slowly, centromere first, towards opposite poles by shortening kinetochore microtubules
-once chromatids separate they are considered to be chromosomes
-there is increasing separation of pole fibers to elongate the cell
Term
telophase (4 things)
Definition
-chromosomes reach opposite ends of the cell
-spindle dibers dissasemble
-chromosomes return to chromatin
-nuclear envelope and nucleolus form around each set of chromosomes and in nucleus respectively
Term
animal cytokinesis
Definition
cytoplasm divides during telophase by pinching inward of cell membrane at midline called cleavage furrow that eventually separates the cell into two new cells through the action of ringed microfilaments
Term
4 steps of plant cytokinesis
Definition
1. as mitosis ends, vesicles cluster at the spindle equator that contain materials for a new primary wall
2. vesicle membranes fuse and the wall material is sandwiched between the two new membranes that lengthen along the plane of te newly forming cell plate
3. cellulose is deposited inside teh sandwich that will eventually form two cell walls. Other deposits will form the middle lamella between the walls and cement them together
4. a cell plate grows at its margins until it fuses with the parent cell plasma membrane but is still thin, so new material is deposited on it.

(all of these cellulose vesicles were formed by the Golgi apparatus that fuse)
Term
results of cell division
Definition
each offspring receives identical copy of oroginal cell's chromosomes and approximately one half of the original cell's cytoplasm and organelles
Term
muscle and nerve cells / skin, digestive tract, bone marrow
Definition
do not divide / divide rapidlythroughout life
Term
experiments to show that controls on cell growth and division can be shut on/off
Definition
cells in petri dish with nutrient broth will grow until they come in contact with one another, and if cells are removed from the center, cells bordering the open space will begin to divide until they have filled the empty space
Term
controllling by injury such as cut in skin or break in bone
Definition
cells around the edge of the injury are stimulated to divide rapidly, and when new cells are produced the healing process begins...things return to normal once controls on growth are restored when its all bettew!
Term
Tim Hunt and Mark Kirshner
Definition
first to discover the name cyclin for proteins that regulate the timing of cell cycle in eukaryotic cells. since their discovery dozens of other proteins have been discovered that also help regulate the cell cycle
Term
cyclin experiment
Definition
a sample of cytoplasm is removed from a cell in mitosis, the sample is injected intoa second cell in G2, and the second cell enters mitosis (this means when injected into a nondividing cell, cyclins start mitosis)
Term
internal vs. external regulators
Definition
respond to events inside the cell and allows the cel cycle to proceed only when certain processes have occurred vs. respond to events outside the cell and directs cells to speed up or slow down the cell cycle
Term
cancer cells
Definition
-don't respond to the signals that regualate the growth of most cells
-can damage surrounding tissues
-may break lookse from tumors and spread
-interfere with regular activities
Term
3 steps of malignancy
Definition
1. cancer cells slip out of their home tissue
2. the metastasizing cells become attached to the wall of a blood or lymph vessel and secrete digestive enzymes onto it so they can cross the wall
3. they creep or tumble along inside blood vessels, then leave the bloodstream the same way they got in and start new tumers in new tissues
Term
what causes loss of growth control
Definition
-control over the cell has broken down b various causes
-astonishing number of cancer cells have a defect in a gene called P53 that usually halts the cell cycle until all chromosomes have been properly repilcated
Term
gametes (whose x and whose x or y) vs. zygotes
Definition
haploid reproductive cells (egg only x, sperm x OR y so it determines sex) vs. fusion of sperm and egg that contains 2n chromosomes (46 in humans)
Term
prophase 1 (3 things)
Definition
-DNA coils tightly into chromosomes
-spindle fibers appear
-nucleus and nucleolus disappear
Term
special occurences in prophase 1(!!) (synapsis, crossing over, genetic recombination, recombinant chromosome)
Definition
synapsis: "coming together" chromosomes line up independently next to their homologues (pair of homologues = tetrad)
crossing over: occurs during synapsis when chromatids within each pair wrap around each other and portions of the chromatids berak off and attach to adjacent chromatids (multiplies the 8 million from independent assortment to create even more genetic variability)
genetic recombination: how the above process allows the exchange of genetic material between maternal and paternal chromosomes
recombinant chromosome: chromosome after crossing over has occured
Term
independent assortment (2 things)
Definition
-homologues can line up randomly during meosis 1 so that 2^n (unique chromosomes) are produced, in humans this means 2^23 or 8 million possible gametes.
-genes don't influence each other's inheritance.
Term
metaphase 1 (2 things)
Definition
-tetrads line up randomly along the midline of the dividing cell
-spindle fibers attach from each pole to the centromere of one of the homologous chromosomes
Term
anaphase 1 (1 thing)
Definition
-each homologous chromosome consisting of two chromatids attached by a centromere moves to an opposite pole (independent assortment!)
Term
telophase and cytokinesis 1 (2 things)
Definition
-chromosomes reach opposite poles
-cytokinesis begins to create new cells containing haploid number of chromosomes (one from each homologous pair, but it has two copies of it because the original cell copied its DNA before meisos!)
Term
overview of meiosis 1 / p2 / m2 / a2
Definition
not proceeded by copying of DNA and in some species nuclear membrane forms proior to meiosis 2 where others it happns directly after meiosis 1 / spindle fibers form and begin to move the chromosomes toward midline / chromosomes move to midline and form single file / chromatids separate and move towards opposite poles
Term
telophase / cytokinesis 2
Definition
nuclear membrane forms around chromosomes in each of four new cells, and in cytokinesis four new haploid cells each containins half of the original cell's number of chromosomes are formed
Term
where meiosis occurs
Definition
-in animals, meiosis produces haploid reproductive cells only within their reproducitve organs (in humans meiosis occurs in the testes and ovaries)
Term
spermatogenesis (2 things)
Definition
-sperm cells = spermatozoa
-diploid reproductive cell (primary spermatocyte) divides meiotcally to form four haploid cells called spermatids that develop into a mature sperm cell
Term
oogenesis
Definition
-results in production of mature egg cells
-diploid reproductive cell (primary oocyte) divides meiotically to form one mature egg called ovum
-during cytokinesis 1 and 2 the cytoplasm of original cell does not divide equally and one cell receives most of cytoplasm that results in 1 egg cell and 3 polar bodies that degenerate
Term
animal life cycle
Definition
zygote (2n) -->multicelled body, mitosis and development (2n) --> meiosis in ovary and testes (form n) --> gametes (n) --> fertilization (form 2n)--> zygote!
Term
asexual vs. sexual reproduction (2 comparisons, 2 asexual, 1 sexual)
Definition
-production of offspring from one parent without meiosis or fertilization vs. through meiosis and fertilization
-genetically identical to parent vs. genetic variation except for twins
-asexual bacteria form unicellular organisms through binary fission or mitosis
-asexual plants form multicellular organisms through budding
-sexual has an evolutionary advantage because it enables species to adapt rapidly to new conditions ( ex. if a disease strikes a crop, a few plants may be genetic variations that make them resistant to the disease so they can survive and reproduce)
Term
genetics vs. classical genetics vs. molecular genetics
Definition
scientific study of heredity (how individuals inherit characteristics from their parents) vs. study of heredity based on fundamental principles Mendel theorized in his experiments with pea plants vs. study of the structure and function of chromosomes and genes
Term
who was gregor mendel (father of genetics!) childhood / pea plants
Definition
Austrian monk born in 1822 and studied statistics at the U of Vienna / observed and experimented with pea plants (7 specific traits each with contrasting characteristics) to see their offspring in 1853 in monastery garden

REMEMBER: HE could control who mated with who!
Term
parts of a plant
Definition
anther: plant's sperm that forms pollen
stigma: plant's female eggs that form egg cells
embryo in seeds: joining of pollen and egg cells (fertilization)
Term
self pollinating vs. cross pollination vs. true-breeding (pure strain)
Definition
pollen fertilizes egg cells in the same flower (true-breeding with no genetic variability) vs. combining reproductive cells from 2 different parent plants vs. offspring genetically identical to parents due to self-pollination
Term
phenotype vs. genotype
Definition
what it looks like (don't forget molecular level like if it creates enzymes) vs. the actual alleles that are present
Term
Mendel's main experiment and his 3 conclusions
Definition
P (parental generation: purple x white) --> F1 (all purple hybrid fowers... self-pollinated to form F2) --> F2 (705 purple and 224 white... recessive traits reappeared!)
Conclusions:
1. inheritance is determined by factors that are passed down
2. genes are the factors that determine traits
3. contrasting characteristics are different forms of a gene called alleles (must have been hybrid in F1!)
Term
dominant vs. recessive alleles
Definition
form of trait that will always be exhibited (usually expressed in capitals, ex. tall plant) vs. form of trait is only exhibited when dominant allele is NOT present (ex. short plant)
Term
Gene "locus" / epistasis
Definition
where gene is located on chromosome / gene a needs to be expressed in order to express gene b (first gene for fur color, second to deposit color)
Term
Law of segregation
Definition
separation of alleles during formation of gametes in anaphase 2 of meiosis ( in mendel's experiment recessive allele reappeared so at some point the recessive allele had to be separated from the dominant one...)

specific example (tall/short)
1. F1 plants inherit 1 tall allele from dad and 1 short allele from mom
2. when gametes are formed, the two alleles segregate from eachother so each gamete has one copy of each gene
3. 2 different types of gametes are formed (one with tall allele and one with short allele) so the dominant and recessive alleles are separated from eachother!
Term
genes / alleles
Definition
segments of DNA on a chromosome that control a particular hereditary trait (occur in pairs) / alternative forms of a gene represented by letters (mom and dad have same genes that are homologues, but different alleles)
Term
probability and independent events
Definition
PROB: # of times an event is expected to happen / # of opportunities for an event to happen

IE:find probability by ultiplying separate probabilities (for really long aabbccddeeff things)
Term
Punnett Square (deffinition / monohybrid vs. dihybrid)
Definition
a diagram showing the possible genetic combinations from a particular cross that can be used to predict and compare the genetic variations that will results from a cross / a cross between individuals that involves one pair of contrasting traits vs. a cross that involves two pairs of contrasting traits
Term
homozygous vs. heterozygous aka hybrid
Definition
two identical alleles (TT or tt) vs. two different alleles for same trait (Tt)
Term
making a punnet square
Definition
1. let statement
2. writing out possible combos of letteres for each parent
3. writing those combos in a punnet square
4. doing punnet square and presenting ratios
Term
dihybrid cross between two hybrids (phenotype ONLY)
Definition
9:3:3:1 ratio of homo dominant, d/r one trait, d/r other trait, recessive
Term
test cross
Definition
cross between individual that determines genotypes by phenotypes (examining offspring allows you to determine the genotype of the dominant individual... ex. black guinea pigs are dominant and if a guinea pig has any brown babies it must be Bb not BB)
Term
incopmlete dominance vs. codominance
Definition
one allele is not completely dominant and recessive allels is not totally masked so heterozygous phenotype is between the two (red RR x white rr snapdragon = pink hybrid flowers)
vs.
both alleles contribute to the phenotype so heterozygous genotype expresses both phenotypes like speckled chicken when white vs. black and blood type too
Term
blood types (4 things)
Definition
-3 different alleles: Ia Ib and i.
-each produce antigens (tags) on surface of RBC
-A and B are codominant so they produce AB blood
-only ii can form type O blood, ia is A and iB is B and ab is AB
Term
give/receive: A, B, AB, O
Definition
A: A and AB / A and O
B: B and AB / B and O
AB: AB / ALL
O: ALL / O
Term
pedigree (diagram of family relationships that shows how a trait is inherited over several generations)
Definition
-circle = female, square = male
-horizontal line = marriage, vertical line and bracket = children (in order from left to right)
-half shaded = carrier, shaded = expresses trait, not shaded = not a carrier and doesn't express trait
Term
single allele trait vs. multiple allele trait
Definition
traits controlled by a single allele of a gene vs. conrolled by three or more alleles of a gene that code for a single trait like ABO blood
Term
autosomal dominant disorders(appear in every generation!) vs. autosomal recessive disorders (acts recessive)
Definition
huntingtons disease (late age o onset, loss of musicle control, mental illness..already have kids!), polydactyly(extra toes and fingers), achondroplasia (specific dominant type of dwarfism)
vs.
sickle cell anemia (serious disorder with a higher incidince in african americans because it prevents malaria, where RBCs are bent, twisted, rigid, and get stuck in capilarries when it should be able to flow single file so the blood stops moving and person doesn't get enough oxygen. in low oxygen, incomplete dominance so even the recessive trait will turn cells sickle-shaped. symptoms include physical weakness, damage to brain, heart and spleen, and may be fatal), cystic fibrosis (gene mutation produces defective proteins so there is faulty transport of Na and Cl across membranes, and difference in water potential because of solutes cause thick mucus to accumulate in lungs)
Term
polygenic traits / environmental influence
Definition
controlled by 2 or more genes (height, skin color, eye color where every combo is a different color for eyes, and just cuz dads 6 foot and moms 5 food doesn't mean you'll be 5'5) / expression of many traits also influence by encironmental factors (ex. height is infuenced by nutrition and disease)
Term
detecting human disorders: gene screening, PKU test, genetic counseling, amniocentesis, chorionic villi sampling, fetoscopy
Definition
GENETIC SCREENING: examination of a person's genetic makeup (ex. karyotyping, blood tests, PKU test)
PKU PHENYLKETONURIA BLOOD TEST: disorder where body can't breakdown phenylalanine: build-up can cuase brain damage; if detected, special diet is followed
GENETIC COUNSELING: medical guidance that informs couples about potential problems in offspring
AMNIOCENTESIS: (14-16 wk) sample of amniotic fluid is removed from the amnion (sac surrounding fegus)
CHRONIC VILLI CAMPING "CVS": (8-10 wk) sample of chorionic villi (tissue between uterus adn placenta)
FETOSCOPY: blood sample withdrawn from baby's umbilical cord

(remember, all are optional and have risks)
Term
heredity
Definition
transmittion of traits from one generation to the next
Term
gamete vs. somatic cell
Definition
sex cell w/ half chromosomes vs. everything but the gametes (all normal diploid cells)
Term
reductional division
Definition
another name for meiosis because it halves the number of chromosome sets per cell (reduction from diploid --> haploid)
Term
3 roles of cell division
Definition
-asexual organisms can divide to form offspring(progeny)
-enables sexually reproducing organisms to develop from a single cell
-helps renew and repair cells (that die or need replacement)
Term
how microtubules shorten during anaphase
Definition
proteins holding chromatids together at centromere deactivate, and kinetochore ends depolymerize to shorten microtubules
Term
M phase checkpoint / growth factors / density-dependent inhibition / anchorage dependence (which internal and which external)
Definition
internal: kinetochores not yet attached at metaphase send signals that cause sister chromatids to remain together / internal: protein released by certain cells that stimulate other cells to divide (pass G1 checkpoint?) / external: crowded cells stop dividing (but because of internal growth factors and nutrients needed) / external: many animal cellsmust be attched to a substratum like container or extracellular matrix
Term
HeLa cells /3 ways to treat cancer
Definition
cell that has been reproducing in culture since 1951 from Henrietta Lacks
/
RADIATION: damages DNA in cancer cells more than normal cells (cancer cells lose their ability to repair this damage)
CHEMOTHERAPY: used to treat known or suspected metatastic tumers, where drugs toxic to actively dividing cells are administered through circulatory system and interfere with specific steps in cell cycle (side effects are nausia from effects on ntestinal cells, hair loss from effects on hair follicle cells, and negative effecton immune system cells)
TAXOL: chemotheraputic drug that feezes mitotic spindle by preventing microtubule depolymerization (can't go past metaphase)
Term
benign vs. malignant tumor
Definition
cancer called by transofmation (converting normal cell--> cancer cell):

abnormal cells remain at original site vs. cancer where tumor becomes invasive enough to impair functions of possibly many organs (cells can metastisize)
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