Genetics Vocab

A piece of DNA that codes for a trait

• Gene 
• RNA
• Allele 

A version of a gene (ex. blond hair or brown hair)

• allele
• gene 
• Phenotype 

The more powerful allele, represented by a capital letter

• Dominant
• Recessive

The weaker allele, represented by a lower case letter

• Dominant 
• Recessive

B = Brown hair

• Dominant
• Recessive

b=blond hair

• Dominant
• Recessive

Two of the same allele (BB, bb)

• Homozygous
• Heterozygous

Two different alleles (Bb)

• Homozygous
• Heterozygous

Homozygous dominant

• BB
• Bb
• bb

Homozygous recessive

• bb
• BB
• Bb