Genetic diversity and adaptation Flashcards
(10 cards)
What is a population ?
A group of organisms of one species living in a particular habitat at a particular time
What is a species ?
A group of organisms that can breed with each other to produce fertile offspring
What is inbreeding ?
Reduces genetic diversity
What is migration ?
Increases genetic diversity
What is a mutation ?
Increases genetic diversity
What is a genetic bottleneck ?
Reduces genetic diversity
A random event which causes a big reduction in a population and so reduces the number of different alleles in the gene pool
What is the founder effect ?
A few organisms from a larger original population start a new population
Natural selection
Mutation
Natural selection starts when a gene mutates and this creates a different version of gene called an allele
Advantage and survival
There is different reproductive success between the organisms with different alleles they can have a allele that makes them able to face challenges posed by the environment so they are more likely to survive and reproduce
Reproduction
Organisms with greater reproductive success leave more offspring
Organisms which have the advantageous allele and are more likely to reproduce
Change in allele frequency
Offspring with advantageous allele are better adapted to the environment so they are more likely to reproduce and pass on the allele
What are the two types of selection
Directional selection as shown by antibiotic resistance (occurs when the environment changes)
Individuals with alleles for an extreme type are more likely to survive and reproduce, some bacteria have alleles that give them resistance to an antibiotic
Stabilising selection
Occurs in an unchanged environment
Three types of adaptations
Anatomical adaptations are structural features
Physiological adaptations are processes within the organism
Behavioural adaptations is the way an organism acts
