| Term | Definition |
|---|---|
| Homozygous recessive | A gene that is expressed only in the homozygous state : ee, qq, ww |
| Homozygous dominant | A gene that is always expressed : AA, KK, TT |
| Heterozygous | Genotypes made up of two different alleles : Dd, Jj, Ss |
| Phenotype | Physical characteristics |
| Genotype | The pairs of genes that make up a trait |
| Complete dominance | The dominant allele completely covers the recessive allele : RR+rr+Rr |
| Incomplete dominance | Neither allele dominates so a new phenotype is shown |
| Codominance | Both alleles are shown : red cow + white cow = red and white spotted cow |
| Diploid | The two sets of chromosomes we inherit from our parents. Twice the haploid number. |
| Haploid | When a cell has half the number of chromosomes after Meiosis. |
| Somatic Cells | The cells that mitosis produces |
| Carrier | A person who has inherited the recessive allele but does not show the trait |
