Genetics Vocabulary Review

Allele The different forms of a gene.

Chromosomes These carry genes that determine the sex of offspring as well as other traits; it is made up of DNA and protein

genes instructions for an inherited trait; an organisms inherited combination of alleles; these are located on chromosomes

mutation Changes in the DNA

DNA The directions or blueprints of life; made up of subunits called nucleotides

heredity the passing of traits from parents to offspring

genetics the study of heredity

recessive Kind of trait that seemed to vanish in the offspring produced in Mendel’s first experiment; the trait that seems to reappear in the second generation; usually indicated by a lower case letter

Punnett Square A tool used to visualize all the possible combinations of alleles from parents

dominant Kind of trait that always appeared in the offspring produced in Mendel’s first experiment; that trait that appears more often.

Genetic Engineering Manipulating the genes within an organism.

heterozygous The combination of two different alleles for an inherited trait

Selective breeding When breeders mate organisms with desirable characteristics

homozygous The combination of two of the same alleles for an inherited trait

phenotype An organism’s inherited physical appearance

probability that mathematical chance that an event will occur Ratio: 3:1 or percent: 75% or fraction 1/4