Genetic Diversity And Adaptation Flashcards
Define genetic diversity
The number of different alleles of genes in a population
Genetic diversity is what allows natural selection to occur
How is genetic diversity in a population increased by
Random Mutations forming new alleles
New alleles when individuals from, another population migrate and reproduce- gene flow
Define evolution
The change in allele frequency over many generations in a population
Natural selections results in species being better adapted to environment
What are the 3 types of adaptations
Anatomical physiological and behavioural
Describe how natural selection leads to evolution
Random mutation results in new alleles of a gene.
the new alleles are beneficial increasing chance of survival,leading to increased reproductive success.
The advantageous allele is inherited by members of the next generation.
over many generations, the new allele increases in frequency in the population
What are the 2 types of selections
-directional
-stabilising
What is directional selection
The individuals beneficial alleles code for an extreme characteristic so more likely to survive and reproduce
It is caused by a change in the environment
Give an example of directional selection
Antibiotic resistance in bacteria
What is stabilising selection
Individuals with alleles for characteristics in the middle of the range becomes the selective advantage so is likely to survive and reproduce- occurs when the environment isn’t changing
Give an example of stabilising selection
Human birth weights
What is behavioural adaptations
Way organisms acts that’s increases chance of survival and reproduction
What is physiological adaptations
Processes inside the organism body that increases chance of survival
What is anatomical adaptation .
Structural features of an organisms body that increases chance of survival- looks
