Genetics Flashcards
Chromosomes
Rod-shaped structures that DNA is organized into.
Gene
A portion of DNA that controls the characteristics of an offspring.
Heredity
The passing of traits from parent to offspring.
Trait
A characteristic of an organism.
Dominant Trait
The trait that is always expressed if the gene is present. It can hide a recessive trait. (Uppercase letters)
Recessive Trait
The trait that is not always expressed. It recedes into the background. (hidden by the dominant trait) (lowercase letters)
Allele
Different forms of the same gene, usually two, one from each parent.
Genotype
The inherited combination of alleles, represented by letters (like TT, Tt, tt).
Phenotype
The physical appearance of a trait (like tall or short).
Homozygous
When the two alleles an organism has are the same. (TT, yy)
Heterozygous
When the two alleles an organism has are different. (Tt, Yy)
Mutation
A change in DNA which may result in a change in the organism.