Unit 6 Bio Vocab

Gene

•  A segment of DNA that codes for a specific trait (e.g., eye color).

Allele 

•  A different version of a gene (e.g., blue vs. brown eye color).

Homozygous Dominant 

•  Having two dominant alleles (e.g., AA).

Homozygous Recessive 

•  Having two recessive alleles (e.g., aa).

Heterozygous 

• Having one dominant and one recessive allele (e.g., Aa).

One Trait Cross 

• A Punnett square that examines one gene (e.g., Aa × Aa).

Two Trait Cross 

• A Punnett square that examines two genes at the same time (e.g., AaBb × AaBb).

Genotype 

• The genetic makeup of an organism (e.g., Aa, AA, or aa).

Phenotype 

• The physical expression of a trait (e.g., blue eyes or brown eyes).

Somatic Cell:

• any cell of a living organism other than the reproductive cells

Karyotypes

• used to examine inheritance and help identify and predict possible chromosomal genetic disorders.