Topic 7A - Genetics

Question 1

Allele

Answer 1

A different version of a gene.
There can be many different alleles of a single of a single gene, but most animals and plants carry two alleles of each gene, one from each parent.
They code for versions of the same characteristics
E.g. Brown eyes (B), Blue eyes (b)

Question 2

Genotype

Answer 2

The genetic constitution of an organism.

The alleles of an organism, BB,Bb,bb for eye colour.

Question 3

Phenotype

Answer 3

The expression of the genetic constitution and it’s interaction with the environment.
An organisms characteristics, e.g. Brown eyes.

Question 4

Dominant

Answer 4

An allele whose characteristic, appears in the phenotype even when there’s only one copy.
Dominant alleles are shown by a capital letter.

Question 5

Gene

Answer 5

A sequence of bases on a DNA molecule that codes for a protein, which results in a characteristic.
E.g. Gene for eye colour.