Evolution

Question 1

Describe the theory behind natural selection

Answer 1

Individuals with phenotypes more suited to their environment are more likely to produce more offspring that individuals with other phenotypes

Question 2

Describe:
Deletion 
Duplication 
Inversion 
Translocation

Answer 2

Deletion - a DNA segment is removed
Duplication - a segment is duplicated
Inversion - a segment is reversed
Translocation - a segment gets moved between chromosomes

Question 3

When are genetic mutations expressed?

Answer 3

Only if they occur within the exon / coding region

Question 4

What are the differences between silent, missence and nonsense mutations?

Answer 4

All are single nucleotide mutations that do not change DNA length
Silent = mutated DNA codes for the same amino acid as the original sequence, no effect
Missense = codes for a different amino acid
Nonsense = mutant DNA sequence is a premature stop codon

Question 5

Are mutations deleterious or advantageous?

Answer 5

Mutations in exons are typically deleterious

Question 6

Ideal conditions for a new allele to replace an old one?

Answer 6

Small population with high mutation rate

Question 7

Genetic drift vs gene flow?

Answer 7

Gene flow = transfer of alleles between populations

Genetic drift = change to allele frequencies within a population

Question 8

Hardy Weinberg equation?

Answer 8

For co-dominant traits =

P^2 + 2pq + q^2 = 1

Question 9

What does HWE reveal about allele frequencies?

Answer 9

If not in HWE, the cause of the allele frequencies requires further investigation as something else must be affecting it

Question 10

How does CRISPR - CAS 9 work?

Answer 10

Involves altering the genome by insertion, deletion or altering DNA sequences

Question 11

What is a polygenic trait?

Answer 11

A trait affected by multiple genes