Mutation selection Flashcards
(12 cards)
1
Q
mutation
A
- any change in nucleotide sequences of an organisms DNA
- most are harmful or neutral
- origin of genetic variation
2
Q
mutation rates
A
how often DNA varies:
- among regions in genome
- among organisms
3
Q
fitness
A
- survival and reproduction
- selection increases frequency of favoured trait in next gen
4
Q
sexual selection
A
- individuals mate preferentially w/ particular individuals
- not at random
- favours traits that enhance chance of reproduction but not survival
5
Q
adaptation process
A
- members of a population become better adapted to environment over the time
6
Q
adaptation characteristics
A
- enhances survival or reproduction in organisms
7
Q
migration
A
- movement of individual/gametes
8
Q
gene flow
A
- migrants survive and reproduce, changes allele frequencies in population relative to rate and direction
9
Q
genetic drift
A
- random changes in allele frequencies from one generation to the next
- random survival
- has larger impacts in smaller population
10
Q
mechanisms in unstable populations
A
- population bottleneck
- founder effect
11
Q
population bottleneck
A
- population is drastically reduced in size
- small no. of survivors may not be representative of original population
- as population grows again, there will be diff. proportions of alleles
12
Q
founder effect
A
- population is started by a small no. of individuals
- unlikely to possess all alleles in gene pool of source population
- rare alleles likely to be lost
