Microevolution 8 Flashcards
What is macroevolution?
Evolution on a grand scales
Like differentiating from human,insect, reptiles and ect
Microevolution?
Changes in gene pool of a population of organisms over time( compared to macroevolution is when it occurs within a species/population)
What is population genetics?
Study of microevolution
Where does Sars-cov 2 come from?
Infected human for the first time in 2019
- Already existed in BATS
- Similar to Sars-cov 2 in bats with a 96% sequence identity
- diverged from the most similar bat virus about 40-70 years ago
What does CONSERVATION genetics study?
Studies how much genetic diversity there is within populations and how it is distributed
What is HEMIZIGOUS?
E.g sex linked chromosome
for example XY, if it affects X, males will have it only in one gene
What is THE OVERALL equation to obtain allele FREQUENCY?
Tot n’ of alleles
In a population of RR,Rr,rr
RR n = 5
Rr = 4
rr = 1
What is the frequency of R and r?
Equation for R(p) =
2 x N of individuals with RR + N of individuals Rr
————————————–
Tot n of individual x 2
10 x 2
= 0.7
r frequency (q)=
2 x N of individual rr + N of Rr individuals
—————————————–
tot N of individual x 2
=
2 x (1) + 4
————-
20=
=0.3
What is the equation for hardy Weinberg equilibrium?
p2 + 2pq + q2
WHat are p and q, allele or genotype frequency?
ALLELE
What are the conditions for HARDY-WEINGBERG equilibrium?(5)
- No selection
- random mating
- no mutation
- Large pop size
- No migration from other populations
- Cystic fibrosis (CF) is caused by a recessive mutation in the
CFTR gene i.e. all patients with cystic fibrosis are
homozygous for the disease-causing allele - About 1/2500 (0.0004) individuals is affected by cystic
fibrosis - Assuming the population is at H-W equilibrium at this
genetic locus, what is the expected frequency of
individuals who are heterozygous for the disease-causing
allele (i.e. carriers)?
-square root of 0.0004 = 0.02 = q
- 2pq
- 2 x 0.02 x 0.98 = 0.0392 Rr heterozygous
What factors lead to change in allele and genotype frequencies?
- Genetic drift - low population size
- Non-random mating
- migration
- selection
How is genetic VARIATION preserved?
- heterozygote advantage
- frequency depedent selection
- Different selective pressures across the geographic
range of the population (convergent evolution)
WHat is the neutral theory?
- States that only small part of the of genetic variation due to NATURAL selection is advantageous