variation

Question 1

Variation can be ..
how?

Answer 1

Genetic = caused by differences in genotype, genotype = entire genetic makeup of an organism .
An organisms genotype can affect its phenotype = the observable characteristics of an organism

An organisms gene are inherited from its parent

Question 2

What else affects an organisms phenotype?

Answer 2

interactions with its environment can influence phenotype= environmental variations
Most variation in phenotype is mix of environmental and Genetic variations

Question 3

Occasionally what may happen to a gene?

Answer 3

gene may mutate

Question 4

Define mutation and what may it result in

Answer 4

rare random changes in an organisms DNA that can be inherited

Question 5

What does genes code for and how do mutations effect it??

Answer 5

genes code for particular sequence of amino acids which make up a specific protein, gene mutations sometimes leads to changes in proteins that it codes for

Most genetic variants have little or no effect on the protein the gene codes for, some change to small extent that function is unaffected = most mutations have no effect on organisms phenotype

Question 6

What can some variants do?

Answer 6

small influence on organisms phenotype
example = eye colour

Question 7

very occasionally, what can some variants do?

Answer 7

dramatic effect that determines phenotype
example = the gene codes for protein that controls movement of water and salt into and out of cells = protein produced by mutated gene doesn’t work properly

therefore build up of excess mucus in lungs and digestive system = hard to breath and digest food

Question 8

if the environment changes, what occurs to the new phenotype ?

Answer 8

makes an individual more suited to the new environment , it can become common throughout species relatively quickly by natural selection