| A | B |
|---|
| continuous variation | have a wide range of values |
| discontinuouis variation | controlled by a single gene |
| allele | dfferent forms of the same gene |
| dominant allele | always expressed if it is presesnt |
| recessive allele | only expressed if both alleles are recessive. |
| genotype | combination of alleles |
| phenotype | physical characteristics |
| homozygous genotype | both alleles are the same |
| heterozygous genotype | two alleles are different |
| genetic code | found in the nucleus of each cell |
