Populations Flashcards
(14 cards)
What is a species?
A group of similar organisms that can reproduce fertile offspring.
What is a community?
All the populations of different species in the same area at the same time
What is a gene pool?
All the alleles in a population
What is allele frequency?
The number of times an allele appears within a population’s gene pool
Why may gene pools change?
Natural selection → Characteristics change → New species
What are the equations for the Hardy-Weinberg principe?
p = homozygous dominant
q = homozygous recessive
2pq =heterozygous
p + q =1
p² + q² + 2pq = 1
What are the assumptions of the Hardy-Weinberg principe?
- Mating is random (no interbreeding)
- The population is large
- There is no migration
- There is no mutation
- Allele frequencies are equal in both sexes
- No selection favouring particular genes
- Organisms are diploid
- Organisms reproduce by sexual reproduction only
biotic?
living factor
abiotic?
non living factor
what is an ecosystem?
The interactions between the biotic and abiotic factors of an environment
What is a habitat?
part of the ecosystem where particular organisms live
what is a niche?
organisms role within their ecosystem. eg. position in the food web
- each species has their own niche, no two species can share a niche
what happens when two species share a niche
they will go into competition with each other
what assumption does hardy wineberg have on the allele frequency?
assumes that there will be no change in the allele frequency between generations within a population
