BIOL 1107 Unit 5: Evolution

what affects the overall characteristics of a populations

frequency of alleles

this is the term for how common the alleles for a gene are in a population

allele frequencies

frequencies are expressed as a

decimal

Flower color is controlled by a single gene with two alleles in snapdragons. Red is dominant to white, and heterozygous individuals have pink flowers. What is the frequency of the recessive allele in a snapdragon population that consists of 568 red, 48 white, and 384 pink individuals?
A. 0.24 B. 0.43 C. 0.05 D. 0.76 E. 0.22

A

in hardy weinberg what is the frequency of A

p

in hardy weinberg what is the frequency of a

q

in hardy weinberg what is the frequency of AA

p^2

in hardy weinberg what is the frequency of Aa

2pq

in hardy weinberg what is the frequency of aa

q^2

what are the 5 assumptions in hardy weinberg

sexual population, autosomal gene, clear generations, two alleles for a gene, diploid organism

for hardy weinberg, what 5 things should be true so that the allele and genotype frequencies do not change

no mutation, random mating, no trait advantages, large population, no migration

Seed color is determined by one gene with two alleles in peas, and yellow alleles are dominant to green. If the frequency of the yellow allele is 0.72 in a population in H-W equilibrium, what percentage of the plants produce yellow seeds?
A. 72% B. 40% C. 92% D. 8% E. 52%

C

Ear length is controlled by one gene with two alleles in rabbits, and long ears are dominant to short ears. If you observe 990 rabbits with long ears and only 10 rabbits with short ears in a H-W equilibrium population, how many rabbits would you expect to be heterozygous?
A. 180 B. 20 C. 810 D. 432 E. unknown

A

MN blood types are determined by a gene on which chromosome

4

are MN blood types clinically significant

no

Assume hair curliness is controlled by one gene with two alleles. Dominant alleles promote curly hair, recessive alleles promote straight hair, and heterozygotes will have wavy hair. Observations from a large population are 71.8% curly, 19.4% wavy, and 8.8% straight hair. Is the population in Hardy-Weinberg equilibrium (assuming that a 3% deviation from expectations is significant)?
A. yes B. no C. I have no idea what is going on.

B

____ is formally defined as a change in allele frequencies of a population over time

evolution

evolution happens when what happens with hardy weinberg

one of the hardy weinberg principles becomes false

Fill in the blanks for when evolution happens
no mutation-->____
random mating-->____
no trait advantage-->____
large population-->____
no migration-->____

mutation
nonrandom mating
selection
genetic drift
gene flow

what is the OG source of genetic variation and is essential for evolution

mutation

what impact does mutation generally have unless coupled with another evolution mechanism
(big or small)

small

If one of the five thousand people who live on a small island was born with a new mutation for the autosomal TP53 gene (heterozygous), what would be the allele frequency of the mutation?
A. 0.0001 B. 0.02 C. 0.004 D. 0.01 E. 0.0002

A

what is the name for when alleles move from one population to another meaning they migrate

gene flow

gene flow of how many individuals will have a significant effect
(a lot or a little)

a lot

can gene flow introduce new alleles in a population

yes

A population of 400 reindeer has a frequency of 0.5 for the dominant allele of a gene. If 100 migrating reindeer with a frequency of 0.8 for the dominant allele join this population, what is the new frequency for the dominant allele?
A. 0.58 B. 0.54 C. 0.60 D. 0.52 E. 0.56

E

what includes any change in allele frequencies caused by a random even

genetic drift

Which isolated population of animals would likely be impacted the most by genetic drift?
A. 72 sharks B. 536 toads C. 18 whales D. 270 bears E. 94 snakes

C

____ ____ refers to change in allele frequencies when new populations arise (immigrants establish new population)

founder effect

in genetic drift, the new population is likely to have the same or different allele frequency to the source population

different

the ____ ____ refers to changes in allele frequencies due to severe population losses (high mortality strikes individuals at random)

bottleneck effect

in bottleneck effect, the population is likely to have the same or different allele frequency than the original source population

different

Willem Schalk van der Merwe was one of the earliest Dutch settlers in South Africa (1658), and researchers believe he is the main source of a high rate of Huntington's disease among descendants of the Dutch (Afrikaners). If the settlers did not interbreed with others, which evolution mechanism contributed to the high rate of Huntington's disease observed today?
A. gene flow B. founder effect C. bottleneck

B

____ happens when individuals have certain heritable traits produce more fertile offspring than individuals without the traits

selection

is selection random or targeted

targeted

T/F selection is the least famous and least powerful

F, most famous and most powerful

what are the three types of selection

natural, artificial, sexual

____ is the ability of an individual to have fertile offspring relative to other individuals

fitness

Which lizard has the highest biological fitness?

Lizard A. Body length 20, offspring 122, offspring surviving to adulthood 19, age at death 4, lizard A is very strong healthy and clever
Lizard B Body length 12, offspring 98, offspring surviving to adulthood 22, age at death 4, lizard B has mated with many lizards
Lizard C Body length 10, offspring 62, offspring surviving to adulthood 28, age at death 4, lizard C is dark colored and very quick
Lizard D Body length 15, offspring 229, offspring surviving to adulthood 26, age at death 6, lizard D has the largest territory of all lizards

C

selection by humans, breeding, creating bananas we know today is what selection

artificial

Artificial selection and genetic engineering (GMO) have essentially the same goal, but are these two processes actually the same?
A. yes B. no C. I'm busy thinking about Christmas

B

This Swedish botanist used observable traits to identify various species

Carolus Linnaeus

T/F Linnaeus' approach was not complex and always worked

F, seemed to work in general, but sometimes incorrectly identifies species

what is a group of organisms that interbreed and produce fertile offspring under natural conditions

species

2 populations that can't or won't interbreed are reproductively isolated from each other and they are considered separate species due to the ____ ____ ____

biological species concept

____ ____ is caused by a variety of things that prevent two groups of organisms interbreeding so the two groups stop exchanging alleles with each other

reproductive isolation

things that result in reproductive isolation are called ____ ____

reproductive barriers

what are the two types of reproductive barriers

prezygotic and postzygotic

this type of barrier is one that prevents mating or fertilization from occurring

prezygotic

this type of barrier is one that acts after fertilization

postzygotic

what are the 6 prezygotic barriers

geographic, temporal, ecological, behavioral, mechanical, gametic

what are the 2 postzygotic barriers

hybrid inviability, hybrid sterility

this barrier is when organisms from different populations are separated from each other by distance or a physical barrier

geographic isolation

this barrier is when different populations are unable to interbreed because they reproduce at different times

temporal isolation

this barrier is when organisms are isolated due to the environments in which they prefer to live

ecological isolation

this barrier is when the presence or absence of a specific behavior prevents reproductions

behavioral isolation

this barrier is when different populations are physically unable to interbreed with each other

mechanical isolation

this barrier is when gametes from different populations are incompatible

gametic isolation

this barrier is when different populations can mate with successful fertilization, but the resulting embryos are unable to develop or are unhealthy and do not survive

hybrid inviability

this barrier is when interbreeding different populations produces healthy embryos, but the resulting offspring are unable to reproduce

hybrid sterility

what barrier is this: finches from the Galapagos Islands are separated by too much water to fly over

geographic isolation

what barrier is this: some species of cicada emerge to mate very 17 years while others emerge every 13 years...so their reproductive season will overlap every 221 years

temporal isolation

what barrier is this: lions prefer to live in open grasslands while tigers prefer wooded areas

ecological isolation

what barrier is this: male fireflies use light patterns to attract females and different firefly species have different patterns

behavioral isolation

what barrier is this: incompatible reproductive organs are common cause for animals while in plants...some populations use a different pollinator to transfer pollen

mechanical isolation

what barrier is this: many marine organisms release their gametes into the water for fertilization, and the eggs and sperm recognize each other through surface proteins, so gamete proteins from a species will not recognize those from another species

gametic isolation

what barrier is this: hybrid embryos of sheep and goats die in the early developmental stages before birth

hybrid inviability

what barrier is this: horses have 64 chromosomes while donkeys have 62, and the offspring have 63 which cannot divide evenly during meiosis resulting in sterility

hybrid sterility

what are the disadvantages of the biological species concepts

cannot be applied to asexual reproductive organisms (prokaryotes) or extinct organisms

critics of the biological species concepts have suggested other criteria to determine species such as ____ and ____

ecological, phylogenetic

this criteria of critics of the biological species concepts is grouping of organisms adapted to certain environmental resources

ecological

this criteria of critics of the biological species concepts is grouping of organisms that share a history due to descent from a common ancestor

phylogenetic

what is the term for 2 or more distinct species forming from a single ancestral species during an extended period of reproductive isolation/divergence

speciation

this is a diagram of hypothesized relationships between species

phylogenetic tree

this is the term for an organism's long hypothesized evolutionary history

phylogeny

this is a branching diagram that describes the inferred evolutionary relationships between select groups of organisms or taxa

phylogenetic tree

how were phylogenetic trees originally constructed based on

observable traits

how are phylogenetic trees now constructed based on

genetic information

the branching points on the phylogenetic tree are called

nodes

____ represent the most common ancestor of descendent lineages on phylogenetic trees

nodes

the lines on the phylogenetic tree are ____ representing evolving lineages

branches

this is the term used for shared derived characteristics or traits that are present in lineages that descend from a node or branch

synapomorphies

synapomorphies are the defining traits of ____ groups

monophyletic

____ groups consist of a common ancestor and all of the lineages that descend from that ancestor

monophyletic

phylogenetic trees were traditionally based on a simple explanation otherwise known as ____

parsimony

this is the concept that the simplest explanation is most likely to be true

parsimony

____ ____ is where different organisms independently evolve similar traits that have the same function rather than inherit traits from a recent common ancestor

convergent evolution

in convergent evolution, the traits are

analogous

who wrote the origin of species and did all of his work on evolution

Charles Darwin

trait variation exists in populations, is this trait variation heritable

yes, some of it

what leads to competition

limited resources

individuals with traits that are beneficial in a specific environment are more likely to survive, what is this called

survival of the fittest

this selection is a pattern where one extreme trait provides greater fitness

directional selection

this selection is a pattern where an intermediate trait provides greater fitness

stabilizing selection

this selection is a pattern in which the extreme traits provide greater fitness

disruptive selection

Birds lay from one to a dozen eggs at a time, but robins almost always lay four eggs. This is an example of which category of selection?
A. artificial B. stabilizing C. directional D. disruptive

B

this selection is a form of selection favoring individuals with traits that increase the ability to obtain mates

sexual selection

what is this an example of: elk antlers used as weapons for males to fight each other for mates and a social sign

sexual selection

this is the idea that females invest more energy in offspring than males in many species

asymmetry of sex

females producing limited offspring looking for attractive males while males produce unlimited offspring mating with any available female leads to ____ between males

competition