Question | Answer |
What is characteristic of X-linked disorders? | males have dx but females are carriers
--> do not pass to offspring |
heterochromatin | condensed DNA |
euchromatin | loose DNA |
Lyon's hypothesis | One of the 2 X's in a female will be inactivated as a Barr body |
A person with 2 barr bodies has ____ X chromosomes | 3 |
Autosomal Dominant | -single copy
-do not skip generations
-equal numbers of affected females and males
-father to son transmission is observed |
What is fitness defined by? | REPRODUCTIVE SUCCESS |
directional selection | selects for trait on one extreme |
stabilizing selection | selects for moderate trait, against extremes |
disruptive selection | selects for both extremes |
Group selection | natural selection acting on the group, not the individual |
Altruism | sacrifices fitness of individual for benefit of group |
Evolutionary success | frequency of alleles of an individual increased |
Species (3) | -be able to interbreed
-be able to produce fertile, viable offspring
-does this naturally |
Are a horse and donkey same species? | NO --> mule offspring is sterile |
Speciation | formation of a new species |
polymorphism | different forms of alleles / traits |
adaptation | genetic change in a population caused by natural selection |
specialization | adaptation of traits to better fill a niche |
Inbreeding increases frequency of __ and decreases ___. | homozygotes / heterozygotes |
Why is inbreeding so bad? | increases frequency of homozy. recessive detrimental alleles |
Bottleneck effect | severe reduction in population size (i.e. natural disaster) |
genetic drift and when does the effect increase? | random change in allele frequencies
--> genetic drift increases as population size decreases |
T / F: Bottlenecks increase the effect of genetic drift? | TRUE |
divergent evolution | same lineage, evolving apart to be more different |
Divergent evolution produces ___ structures. | homologous |
homologous structures | structures that are embryologically similar but have different functions
(i.e. whale flipper and human arm) |
parallel evolution | same lineage, evolving separately but using similar mechanisms |
convergent evolution | genetically unrelated species acquire same biological trait |
analogous structures | structures that do the same job but have different origins
(i.e. bird wings and bee wings) |
coevolution | two species reciprocally affect each other's evolution (prey and predator) |
parasitism | one benefits, other harmed |
commensalism | one benefits, other unaffected |
mutualism | both species benefit |
ontogeny vs. phylogeny | -development through life of an organism
-development through history of lineages as they change through time |
Ontogeny Recapitulates Phylogeny Theory | This phrase suggests that an organism’s development will take it through each of the adult stages of its evolutionary history, or its phylogeny |
Molecular Clock Theory | -measure of evolutionary change over time at molecular level
-specific DNA seq / px spontaneously mutate at constant rates
-that rate can be used to estimate how long ago 2 organisms diverged from common ancestor |
What are neutral mutation? | random genetic drift mutations that are not acted on by natural selection |
What is Oparin and Haldane's theory on origin of life? | organic molecules created by atmospheric gases zapped by lightening
--> fall into ocean to make primordial soup (C,H,N,O) |
What experiment confirmed origin of life theory? | Urey-Miller |
RNA World Hypothesis | RNA is precursor to current life because RNA can store genetic info and catalyze chemical rxns |
protocells | aggregates of RNA and px inside lipid envelopes |
How did eukaryotes evolve? | -endosymbiosis --> big cx engulfed a smaller cx |
What are 2 types of endosymbiosis? | -heterotrophs engulf mito
-autotrophs engulf chloroplasts |
How did prokaryotes evolve? stages | anaerobic heterotrophs --> anaerobic autotrophs --> aerobics |
What is a chordate? | one of the phylums in the kingdom Animalia |
What are features of a chordate? | notochord, gill slits in embryo (pharyngeal pouches, branchial arches), dorsal nerve cord |
What is a vertebrate vs. chordate? | vertebrates are a subphylum of chordates |
Chordates vs. vertebrates | -all chordates have a notochord, dorsally located nerve
-all vertebrates have a backbone |
Are all vertebrates chordates? Are all chordates vertebrates? | YES / NO |
Notochord | rigid rod present at some stage of development in all chordates |
p + q = | 1 |
Hardy Weinberg equation | p^2 + 2pq + q^2 = 1 |
5 assumptions of Hardy-Weinberg | -large population (no genetic drift)
-no mutation
-no migration
-random mating (no sexual selection)
-all genes are equally successful at reproducing |
What is a back-cross? | mating btwn offspring and parent |
What is a test-cross? | Situation when you have a dominant phenotype (Aa or AA)
--> cross with homozygous recessive aa |
locus | location of a gene on a chromosome |
allele | variant of a gene |
Where do all alleles of the same gene exist? | same locus |
How many alleles does each gene hold? | 2 - one from mom, one from dad |
leakage | gene flow from one species to another
--> concern for antibiotic resistance |
gene pool | all of the alleles in a population |
penetrance | frequency genotype will result in phenotype (whether you have it or not) |
expressivity | to what degree a penetrant gene is expressed |
When does tetrad formation occur? | meiosis I |
In meiosis, are the daughter cells identical to parent cell? | NO |
What does meiosis produce? | haploid (n) daughter cells |
the law of _______( segregation or independent assortment) is dependent on the random arrangement of homologous chromosomes at the metaphase plate during Meiosis I. | independent assortment
--> sometimes mom's chromo is on left, sometimes it's on rightW |
The law of_____ ( segregation or independent assortment) is dependent on the separation of members of homologous pairs. | segregation |
What is the site of crossing-over called? When does chiasma occur? | chiasma / tetrad formation |
What lines up during meiosis I? Mitosis? | homologous chromosomes / sister chromatids |
How many recombinants does a single crossover create? | 2 / 4 |
Where are all of the sex-linked alleles located? | x chromosome |
cytoplasmic inheritance | inheritance of things other than genomic DNA
--> all cellular organelles such as mito are inherited from mother |
mitochondria inheritance is from? | mother |
inversion mutation | stretch of DNA breaks off and reattaches in opposite orientation |
addition / insertion mutation | extra base is added to DNA sequence |
What to addition / deletion mutations create? | frameshift mutation |
translocation mutation | stretch of DNA breaks off and reattaches somewhere else |
inborn errors of metabolism | genetic dx resulting in faulty metabolism
--> PKA where ppl can't metabolize Phe |
Are all mutagens carcinogens? Are all carcinogens mutagens? | NO / MOSTLY YES |
some cancer can be mitogens, what is a mitogen? | increase mitosis |
carcinogen vs. mutagen | -mutagen = causes mutation
-carcinogen = causes mutation that causes cancer |
vestigial structures | remnants of organs that have lost ancestral fxns |
Do species, individuals, or populations evolve? | populations |
Does chordate mean having a backbone? | NO --> bilateral symmetry |
All vertebrates belong to what phylum? | chordata |
r-selection | produce large number of offspring that mature rapidly with littler or no parental care |
k-selection | small brood size with slow maturing offspring and strong parental care |
adaptive radiation | single ancestral species gives rise to a number of different species |
What carries out long-term evolutionary changes? | natural selection |
coacervates | colloidal droplets made of polypeptides, nucleic acids, polysaccharides
--> first cx thought to evolved from this cx type |
prezygotic isolating mechanisms vs. postzygotic | -prevent zygote formation completely
-offspring are inviable |
inclusive fitness | number of alleles organism passes on to next generation |
What ultimately creates evolution? | changing gene frequency |
How to calculate the number of possible gametes for AaBbCc? | 2^n (n =3) |
Why does inbreeding reduce fitness? | increase incidence of expression of deleterious recessive traits |
What organisms fall under eukaryotes? | animls, plants, fungi, protozoans |
Which organisms fall under prokaryotes? | bacteria (kingdom monera) |
What are simplest eukaryotes? | protists |
Some characteristics of x-linked recessive dx? | -more common in males
-skip generations
-NO father-son transmission |
What does the Hardy-weinberg equilibrium oppose? | intro of new alleles into a population |
Gram positive appear ___ after staining.
Gram negative appear ____. | blue / pink |
Where do sperm undergo maturation? What is that analogous to in a female? | epididymis / ovary |
Characteristics of yeast cells | membrane-bound organelles, chitin wall |
What is the smallest and achiral a.a.? | glycine |
What is the imino acid? | proline --> helix breaker |
What a.a. can form disulfide bonds? | cysteine |
Background extinction vs. mass extinction | -background = steady loss
-mass = abrupt loss |
Founder effect | entire population gene pool is based on genes of individuals that founded population |
What is estrogen synthesized from? | testosterone |
Generation time | avg. amount of time btwn appearances of 2 successive generations (i.e. parent and offspring) |
What does LH bind to in males? | leydig cells --> stimulate testosterone release --> FSH |
all bacteria require ____ for growth and reproduction | carbon |
autotrophic bacteria | bacteria that get carbon from CO2 |
heterotrophic bacteria | bacteria that derive carbon from organic nutrients like sugar |
cyanobacteria | use sunlight to produce sugars from CO2 |
What eukaryotic organelles are derived from endosymbiotic bacteria? | mito and chloroplasts |
Rank severity of damage: nonsense, silent, missense | nonsense > missense > silent |
Where is rRNA produced? | nucleolus |
What is the largest organelle in the cell? | nucleus |
How many sets of tumor suppressor genes does each person have? | 1 |
Human diet consist mostly of what type of sugar? | sucrose = glucose + fructose |
Do erythrocytes have organelles? | NO |
Where do erythrocytes get ATP? | cytoplasm and cx membrane supplies erythrocytes |
population | group of interbreeding individuals of same species isolated from similar groups of same species |
fundamental niche | potential conditions under which an organism can survive |
realized niche | conditions individuals actually use to survive |
Are analogous structure evolutionary related? | NO |
Type A blood makes antibodies against? | Type B blood |
When a population undergoes bottleneck, what is genotype of population? | homozygous |
High degree of phenotypic plasticity? | environmental factors influence phenotype |