traits, genes, and alleles 6.3 6.4 terminology for the success of genetics
TRANSCRIPT
Traits, Genes, and Alleles 6.3 6.4
TERMINOLOGY FOR THE SUCCESS OF GENETICS
FATHER OF GENETICS
Term: TRAIT
• Biological factor being studied.
• Example: A blood disease like hemophilia or bleeder’s disease!
Term: DOMINANCE:
• THE PREDOMINANT FORM OF A GIVEN TRAIT.
• Example: Brown eyes are dominant to blue eyes.
Term: RECESSIVE
• A form of a trait not expressed frequently.
• Example: Being left handed!
Term: Gene
• A DNA unit of heredity located on a chromosome that controls traits!
• Example: Look at the “Human Genome” chart on the side board that shows genes for given characteristics!
Term: ALLELE
• A gene for a given trait:
• Examples:
• A
• B or
• O for blood types
Term: HYBRID
• A condition resulting from the cross of two, pure, contrasting traits of a given characteristic such as eye color.
Example:
BB x bb
Bb = Hybrid!
Term: PHENOTYPE
• Physical appearance of a given characteristic.
Example: Type A blood
Eye color - Brown or blue
Right or left handed
Term: GENOTYPE
• The allele expression of a given characteristic.
• Example: BB, Bb, or bb.
• BB - HOMOZYGOUS DOMINANT
• bb - HOMOZYGOUS RECESSIVE
• Bb - HETEROZYGOUS
Quiz
• XX• tt• Yy• zz• Oo• TT• AA• jj
• Tt• Bb• Ii• Kk• Nn• NN• Nn• rr