Week 4- Population genetics

Question 1

what is population genetics

Answer 1

application of genetic principles to entire populations of organisms

Question 2

why is there genetic composition and changes in population genetics

Answer 2

natural selection etc

Question 3

what is a population

Answer 3

group of organisms of the same species living in the same geographical area

Question 4

what is a subpopulation

Answer 4

any of the breeding groups within a population among which migration is restricted

Question 5

what does a gene pool consist of

Answer 5

all the alleles for all loci in a population

Question 6

when is a locus fixed

Answer 6

if all individuals in a population are homozygous for the same allele

Question 7

what is hardy Weinberg equilibrium

Answer 7

a type of model used by biologists to study populations

Question 8

what does Hardy-Weinberg equilibrium state

Answer 8

the genotype frequencies in a population remain constant between generations in the absence of disturbances by outside factors

Question 9

what is Hardy-Weinberg equilibrium used to estimate

Answer 9

the number of homozygous and heterozygous variant carriers of a gene based on its allele frequency in populations that are not evolving

Question 10

what is Hardy-Weinberg equilibrium used for

Answer 10

to describe a non-evolving population

Question 11

what are the 5 conditions for genotype frequencies to stay the same

Answer 11

1. large population size
2. no migration
3. no net mutations
4. random mating
5. no natural selection

Question 12

how many genotypes are at a locus for a diploid organism

Answer 12

3: Aa, AA, aa

Question 13

what is the frequency of all genotypes in a whole population

Answer 13

1

Question 14

what is the Hardy-Weinberg equilibrium equation

Answer 14

p2 + 2pq + q2 = 1
1 = p + q

Question 15

what does P= ?

Answer 15

Frequency of the dominant allele

Question 16

what does q= ?

Answer 16

frequency at the recessive allele

Question 17

what is p2

Answer 17

frequency of homozygous dominant genotype

Question 18

what is q2

Answer 18

frequency of homozygous recessive genotype

Question 19

what is 2pq

Answer 19

frequency of heterozygous genotype

Question 20

how is allele frequency calculated

Answer 20

number of copies of a specific allele in a population / total number of all alleles of that gene in a population

Question 21

how is genotype frequency calculated

Answer 21

number of individuals with a particular genotype in a population / total number of individuals in a population

Question 22

what test can be used to check whether deviation is larger than expected by chance

Answer 22

chi-square test

Question 23

what are Y chromosomes

Answer 23

patrilineal

Question 24

what are the two types of genetic markers of Y chromosomes

Answer 24

• Y-STRs
• Y-SNPs

Question 25

what is mtDNA

Answer 25

matrilineal

Question 26

what is typically sequenced

Answer 26

control region of the mtDNA

Question 27

what is the haplogroup assigned by

Answer 27

the presence of specific DNA mutations

Question 28

what is SNP

Answer 28

single nucleotide polymorphism

Question 29

what is a haplotype

Answer 29

can refer to a combination of alleles or set of SNPs

Question 30

what is haplogroup

Answer 30

group of people who share a common ancestor on the patriline or matriline

Question 31

what has driven evolutionary change

Answer 31

- viruses - positive natural selection

Question 32

what is 8% of the human genome compromised of

Answer 32

retroviruses at various stages of fossilisation

Question 33

what is retroviruses at various stages of fossilisation

Answer 33

- non-coding DNA - Human endogenous retrovirus

Question 34

what is human endogenous retroviruses

Answer 34

Endogenous viral elements in the genome that closely resemble and can be derived from retroviruses

Question 35

why are hERVs incapable of replication and contain major deletion or nonsense mutations

Answer 35

because they are merely traces of original viruses, having first integrated millions of years ago

Question 36

what is syncytin

Answer 36

domestication of a retroviral envelope gene env

Question 37

what does syncytin do

Answer 37

mediate nutrient transfer from the to the developing embryo in placental mammals

Question 38

why do all infants have a high lactase enzyme activity

Answer 38

to digest the sugar lactose in milk

Question 39

when does lactase enzyme activity decline in most humans

Answer 39

after weaning

Question 40

which genes can become resistant to malaria

Answer 40

- haemoglobin - enzymopathies - RBC antigens - immune genes

Question 41

how does haemoglobin become resistant to malaria

Answer 41

inherited disorders of HB structure and function

Question 42

what variants are present at substantial frequencies in any population, in the HbB gene

Answer 42

S, C, E

Question 43

what does S variant lead to

Answer 43

sickle cell anaemia

Question 44

what does C variant lead to

Answer 44

?

Question 45

what does E variant lead to

Answer 45

lover levels of HbB and mRNA