Biology - Variation and Evolution

what is a species?

group of similar organisms that can naturally interbreed and produce fertile offspring

what is variation?

differences between members of the same species.

what are the types of variation?

inherited variation, acquired variation

what is acquired variation?

not inherited but learned through life

what is inherited variation?

passed down from one generation to the next and is controlled by genes

what are the causes of inherited variation?

mutations and sexual reproduction

what are the causes of mutations?

mutagens

types of mutagens

uv radiation, tobacco smoke

types of mutations

gene mutation, chromosome mutation

what is gene mutation?

change in a single gene

examples of gene mutation

cystic fibrosis, sickle cell anemia

what is chromosome mutation?

a change in the number of chromosomes

explain sexual reproduction as a cause of inherited variation

the different variations of chromosomes that may enter a gamete is very high

what is evolution?

the way which living things change genetically to produce new forms of life over long periods of time

give an account on the theory of natural selection

darwin and wallace, population remains constant due to competition, variation because of sexual reproduction/ mutations, help them adapt to their environment - survival of the better adapted or fittest and better adapted pass on their positive traits, over long periods change in genetics results in a new species forming