lecture 17

Question 1

what is the human genome?

Answer 1

it doesn’t exits, ppl differ by thousands of genetic changes in genome sequence

Question 2

what are mutations and how do they happen? 2.0

Answer 2

ultimate source of genetic variations, they are caused by DNA replicated errors and is a natural non directed process resulting from chem + phys of DNA copying process

Question 3

what is recombination and how does it happen?

Answer 3

it repackages/creates new mutation combos in pop and increases genetic variation
it happens in meiosis
it happens when gametes align and crossover happens b/w chromosomes

Question 4

how does random genetic drift happen and how does it impact allele/gene frequency?

Answer 4

it happens purely due to random change of which genetic combo makes it to each gen and has no relation to organism features
it reduces genetic variation as by random change some genetic combos might not make it to the next gen

Question 5

what is deleterious selection?

Answer 5

this is when mutations which reduce fitness are reduced/removed by natural selection

Question 6

what is positive selection and how does it affect gene/allele frequency?

Answer 6

adaptions that increase fitness will spread and become fixed in pop
genetic diversity will be reduced as all pop will gain the same beneficial variation

Question 7

how can heterozygosity impact selection?

Answer 7

when there is a heterozygous advantage, selection will act to maintain diversity over longterm/avoid fixing genes

Question 8

what is gene flow?

Answer 8

when mutations in one pop infiltrate another pop and this influences diversity structure over large spatial scale and decreases genetic diff b/w two pops

Question 9

what causes genetic variation to increase in a pop and what causes it to decrease?

Answer 9

mutation, recombination, migration cause increased genetic variation in a pop, while genetic drift causes it to decrease
natural selection can cause it to either decrease or increase depending on what type of gene/genotype is advantageous

Question 9

what causes genetic variation to increase in a pop and what causes it to decrease?

Answer 9

mutation, recombination, migration cause increased genetic variation in a pop, while genetic drift causes it to decrease
natural selection can cause it to either decrease or increase depending on what type of gene/genotype is advantageous

Question 10

what is electrophoresis and how is it done?

Answer 10

it’s a process that uses gel to discover what genes in pop are polymorphic (variable)
chemistry is done on ground-up tissue of individuals Iand placed in gel where electric currents are applied
the tissue/protein will then move across the gel at diff speeds based on size/polarity

Question 11

what are allozymes?

Answer 11

diff forms of the same protein (used in conjunction w/ electrophoreisis

Question 12

what are polymorphic genes (in electrophoresis context)

Answer 12

genes that have more than one allele at a locus (slow + fast)

Question 13

what are monomorphic genes?

Answer 13

homozygous genes (all fast/slow)

Question 14

what are the advantages to electrophoresis?

Answer 14

provides tool to examine amount of genetic variation
many loci can be examined
can be used w/ any organism
loci codominates, heterozygotes can be identified
variations can be examined close to fna level
provides genetic mark loci for many diff studies
can compare loci of diff species

Question 15

what is variation selectively neutral?

Answer 15

if a variation doesn’t affect fitness, it probs won’t be affected by natural selection

Question 16

what is the neutral theory?

Answer 16

it suggests large fraction of genetic variaton is selectively neutral