| Genotype | - The symbolic representation of a pair of alleles e,g, BB or Bb |
| Phenotype | - The 'observable' characteristics or traits e.g. Blue eyes
- Due to genotype, environment, genotype-environment interaction |
| Dominant Allele | - The Allele always expressed (capital letter) |
| Recessive Allele | - The Allele only expressed in homozygous form (lower case) |
| Co-Dominant Allele | - A pair of alleles that both affect the phenotype (e.g. AB blood group)
- When both alleles are expressed in the phenotype e.g. siclcle cell amamenia |
| Homozygous | - 2 identical alleles e,g, BB or bb |
| Heterozygous | - 2 different alleles e.g. Bb |
| Multiple Alleles | - When a gene has more than 2 alleles (e.g. Blood type) |
| Carrier | - An individual with a one recessive allele that is not expressed in phenotype |
| Diploid | - A cell that has a set of maternal and paternal chromosomes (46 in humans) |
