Bio 108 Evolution and Heritability

evolution

change in genetic frequencies in a population over generations

population

group of organisms of the same species that interact and interbreed

Evolution happens at a ______ level

Population

gene

genetic sequence that codes for a protein

Alleles

how a gene is expressed

incomplete dominance

possibility of expressing both alleles (blending)

co-dominance

expressing both alleles separately

epistasis

more than one gene impacts a trait

plieotrophy

one allele impacts multiple traits

True or False: there is only two allele options

false

What do gonads (reproductive organs) produce

gametes

haploid

one set of DNA so when fertilization occurs it can become diploid

recombination and random assortment

how genetic variation occurs in gametes during meiosis

Homologous Chromosomes

Chromosomes containing the same type of genetic organization

recombination

DNA exchange in homologous chromosomes (first step of genetic variation in gametes)

independent assortment

homologous chromosomes randomly line up when separating

central dogma of biology

the conversion of DNA to mRNA

Transcription of DNA —>

mRNA

mRNA —>

ribosome

Ribosome —>

translation into protein

How are new traits created

mutation

ontogeny

development throughout an organism’s life

phenotypic plasticity

change in phenotype in response to environment

common garden experiment

testing whether a trait is naturally selected or phenotypic plasticity by placing two organisms from different populations in the same environment

ability to survive and reproduce

two variables showing how high an organisms fitness

false

true or false: aquired traits are heritable

differ

individuals ____ from one another (requirement for NS)

inherited

variation is ___ (requirement for NS)

success, reproducing, surviving

individuals differ in ___ at ______ and _______

directional selection

mean of a trait shifts to one extreme

stabilizing selection

mean of graph stays the same but the range shrinks

disruptive selection

increase in traits on the two extremes but decreases in middle

fixation

frequency of trait is 100%

point/substitution mutation

one nucleotide replaced w a different nucleotide during replication

deletion

one nucleotide removed from DNA sequence

insertion

addition of a nucleotide

duplication

sequence is duplicated

inversion

DNA flipped around and inserted backwards

chromosomal fusion

two chromosomes fuse

aneuploidy

entire chromosome duplicated or lost

genome duplication

all DNA in a cell is duplicated

true

true or false: adaptive traits are not necessarily good because they may not be suitable for other environments

gene flow

movement of alleles b/w two populations

true

True or False: Populations with high gene flow are more similar because the mixing of traits eventually evens out the distribution of alleles

False

True or False: gene flow, natural selection, and genetic drift produce new alleles

genetic drift

evolution by random chance

false

True or False: genetic drift is more prominent in larger populations

sexual selection

differences in reproductive success caused by competition over mates and related to expression of a trait

anisogamy

different gametes —> harder to make eggs

bateman’s principle

male reproductive success increases with increases w number of mates while female reproductive success does not

intrasexual selection

same sex competition

intersexual selection

opposite sex competition

choosiness

amount of effort an organism puts in to finding a mate

species

evolutionary independent population or group of populations

biological species concept

species consist of populations that are reproductively isolated

morphological species concept

populations consistently morphologically distinct from one another

phylogenetic species concept

populations that are the smallest monophyletic group on a phylogenetic tree

Hardy Weinberg Equilibrium

helps measure change by describing a population where there is no evolution happening (acts as a control to compare change), allows you to predict future generations —> null hypothesis

conditions for null hypothesis

no natural selection, no genetic drift, no gene flow, no mutation, no random mating