Genetics

Definitions:

Allele - Alternative forms of a gene occupying a position on a chromosome.
Heterozygous - has two different alleles (example Rr).
Homozygous - has two alleles the same (example RR or rr).
Genotype - The genetic constitution of an organism.
Phenotype - the appearance determined by the genotype (example red)
Dominant - out of the pair of alleles this is the one which takes effect or appearence and is usually represented by a capital letter (example R)
Recessive - An allele that affects the phenotype of the organism only if a dominant allele is not present.

Mendels 1st Law - Law of Segregation

Characteristics of an organism are controlled by pairs of alleles that separate in equal numbers into different gametes as a result of meiosis.

Mendels 2nd Law - Law of Independent Assortment

Two or more pairs of alleles segregate independently of each other as a result of meiosis, provided the genes concerned are not linked by being on the same chromosome.