GVR: Genetic diversity and adaptation Flashcards
Define Genetic Diversity:
The number of different alleles in a population.
Define phenotype:
The expression of a genotype and its interaction with the environment.
How are new alleles produced?
Mutations.
What are the three types of natural selection?
- Stabilising selection
- Directional selection
- Disruptive selection
What is stabilising selection?
- Favours intermediate phenotypes
- Extreme phenotypes are disadvantaged
What is directional selection?
- Favours extreme phenotypes
- Intermediate phenotypes are disadvantaged
Give an example of stabilising selection:
Human birth weight
Give an example of directional selection:
Antibiotic resistance
What is evolution?
A change in the allele type and frequency in a population.
How are new alleles of a gene created?
Mutation of the DNA base sequence.
Define interspecific competition:
When individuals of different species compete for the same resources in an ecosystem.
Define intraspecific competition:
When individuals of the same species compete for resources in an ecosystem.
What is an extremophile?
An organism that can successfully survive and reproduces in extreme environments.
What is an adaptation?
A long-term response by which a species becomes fitted to its environment.
What are the three types of adaptations?
- Anatomical
- Behavioural
- Phisological