Summary Genetic diversity and adaptations (selection) A level Biology

Genetic diversity and adaptations (selection) summ
03 March 2023 12:49



Genetic diversity- total number of different alleles in a population
Population- group of individuals of the same species that live in the same place and can inter
- Species consist of one or more population
- Greater the number of different alleles that all members of a species possess, the grea
that species
- Genetic diversity reduced when a species has fewer different alleles
- More genetic diversity means species is more likely to survive environmental change -
wider range of characteristics - greater probability that individual will possess a charac
environmental conditions
- Allows natural selection to occur

Genetic diversity comes from- crossing over, independent segregations, random fertilisation


Natural selection

Reproductive success and allele frequency
- Within any population of a species there is a gene pool- contains wide variety of allele
- Random mutation leads to new alleles
- Might give possessor of allele an advantage over other individuals
- Better adapted to environment
- More likely to survive
- More likely to reproduce
- Pass on alleles
- Gametes also have advantageous allele




Types of selection

Directional selection