NATURAL SELECTION

Question 1

What is genetic diversity?

Answer 1

The total number of different alleles in a population

Question 2

What are the principles of natural selection?

Answer 2

Random genetic mutations result in new alleles of a gene
In this case, the new allele benefits the possessor in their environment, increasing reproductive success
The possessors survive longer than non-possessors, and the advantageous allele is inherited by the next generation
Over many generation, the allele increases in frequency in the population

Question 3

What is directional selection, + an example?

Answer 3

When environmental conditions change, organisms with phenotypes best suited to the new conditions survive longer; the population mean shifts towards these characteristics

Longer necks in giraffes

Question 4

What is stabilising selection + an example?

Answer 4

When environmental conditions stay the same, individuals closest to the mean are favoured, individuals far away are selected against

Birth mass in newborns