Biology-Variation and The human genome project

Question 1

What are the two cause of variation within a species

Answer 1

Genetics
Environment

Question 2

What is genetic variation

Answer 2

variations in the genotypes of organisms of the same species due to the presence of different alleles

Question 3

What creates genetic variation in a species

Answer 3

Spontaneous mutations
Sexual reproduction

Question 4

What is a mutation

Answer 4

A random change to the base sequence in DNA which results in genetic variants

Question 5

State the three types of gene mutation

Answer 5

Insertion
Deletion
Substitution

Question 6

The three ways a gene mutation can affect an organisms phenotype

Answer 6

Neutral mutation- doesn’t change the sequence of amino acids, protein structure and function stay the same, no effect on phenotype

mutation may cause a minor change in an organisms phenotype eg. change in eye colour

mutation may completely change the sequence of amino acids. This may result in a non functional protein. Severe changes to phenotype.

Question 7

What is environmental variation

Answer 7

variations in phenotype that are acquired during the lifespan of an organism due to environmental factors