Combination of alleles that control each characteristic = Genotype

Observable characteristic of an organism = Phenotype

Dominant = Only need 1 to make phenotype present

Recessive = Need both to make phenotype present

Homozygous = Two alleles of gene are same, AA, aa

Homozygous Recessive = aa

Homozygous Dominant = AA

Heterozygous = Two alleles of gene are different, Aa

The term ‘pure breeding’ indicates that the individual is homozygous for that characteristic

Example -

Things needed =

1. Punit square with ruler
2. label gametes
3. mention parents
4. Draw circles

Pedigree Charts -

Used to trace pattern of inheritance through generations

• The family pedigree above shows:
  • both males and females are affected
  • every generation has affected individuals
  • That there is one family group that has no affected parents or children
  • the other two families have one affected parent and affected children as well

MALES = SQUARE