Processes of evolution

Question 1

What is a species?

Answer 1

the generation of a reproductively isolated po

Question 2

What is the biological species concept

Answer 2

States that species is interbreeding group that makes fertile offspring

Question 3

Identify and explain the four main mechanisms leading to evolution?

Answer 3

nat selection – inc allele freq, produces adaptaton,

, genetic drift – random fluctuation in allele freq, Random in selection and population size

, gene flow, - opposite of genetic drift , Reduces genetic diversity between pop. Makes pops more similar to each other

Mutation – introduces new alleles, uusually not successful.

Question 4

Why is artificial selection natural selection? Why might we consider it different

Answer 4

This could be natural selection because we are a species, homo sapiens and it is the pressure we induce on another species that causes it to change. It might be considered something different because we do it intentionally.

Question 5

Why is genetic drift an important issue concerning the conservation of species?

give ex

Answer 5

A bottle neck causes one allele to disappear entirely, in a small population with low diversity this could be bad. Low diversity means possibility of interbreeding and also one sickness could wipe them all out.

Question 6

What are the 3 mechs of speciation

Answer 6

Allopatry - geological
Parapatry - theres a hybrid zone, hybrids become their own species, slow
Sympatry - symbiotic animals change hosts and stay on hosts.

Question 7

Identify two mechanisms for speciation and explain their links to evolution.

Answer 7

Allopatry
parapatry
Sympatry
The animals can no longer interact for whatever reason. causes them to evolve independantly and make a new species

Question 8

what is genotype

Answer 8

complete set of genes in an organism
genetic info inherited from parents

Question 9

What is phenotype

Answer 9

set of observable chars on an org. determined by the genotype and env

Question 10

Why is hardy weinberge princple a null hypothesis

what is it, eq, what does it do

Answer 10

p^2 +2pq +q^2 = 1

how to know if evolution is happening or not

Analyze the allele freq before and after random mating

Randomly combines all gamates

Predicts genotypes and freq of genotype
The hardy weinberg should be proven false always because evolution should be happening

Question 11

What are the fundamental claims of the hardy weinberg principel

Answer 11

If A = p and a = q then the freq of the genotypes Aa, AA and aa will equal p^2, 2pq, q^2 for every gen
Frequencies of alleles do not change over time

Question 12

what 5 conditions are met for hardy weinberg to work

Answer 12

1) no natural selection
(2) no genetic drift
(3) no gene flow
(4) no mutation
(5) random mating

Question 13

Use terms allel, dominant, recessive to differentiate homo and heterozygous genotype

Answer 13

Dominent is A
recessive is a
Homo is AA or aa
Hetero is Aa

Question 14

What is a prezygotic barrier? types
5

Answer 14

Stops zygote from forming
geo - diff places
temperal - diff times
behavioral - diff ways of mating, dancing
morphological - not fitting
genetic - sperm wont work on egg

Question 15

What is a postzygotic barrier, types

Answer 15

Hybrid depression - hybrids not as well liked among either types
ex mallards and black duck hybrid
- hybrids die before maturity
-hybrids sterile
ex mules

Question 16

What are the types of natural seleciotn

Answer 16

Directional - inc allele frq in one direction, reduce diversity
divergent - selects against intermediate, reduces genetic difersity into 2 directions
sexual - when the selective force is for mating, those with better fitness. Sometimes reduces diversity
artificial selection? - reduce diversity, done by humans