Genetics Vocabulary
Genetics is the scientific study of heredity.
Heredity is the passing of traits from parents to offspring.
Traits are physical characteristics that organisms pass on to offspring through traits.
Purebred means an organism has 2 same alleles for a trait, or homozygous.
Hybrid means an organism has 2 different alleles for a trait, or heterozygous.
P Generation means the parental generation, or the original organisms used in a genetics experiment.
F1 Generation means the generation produced by crossing P generation organisms. “F” stands for
filial which means “son” in Latin.
F2 Generation means the generation produced by crossing F1 generation organisms.
Genes are segments of DNA on a chromosome that codes for a specific trait or protein. Genes are lined
up in the same order from one end of the chromosome to the other.
Alleles are the different forms of a gene. Organisms get two, one from each parent.
Dominant Allele is the form of a gene that always shows in the organism when the allele is present.
Recessive Allele is the form of a gene that is masked whenever the dominant allele is present.
Probability is the likelihood that a particular event will occur.
Punnett Square is a chart that shows how alleles are divided up into sex cells and the possible
combinations of alleles that can result in offspring.
Genotype is the combination of alleles for a trait.
Phenotype is an organism’s physical appearance, which could be affected by environment.
Homozygous means the same 2 alleles for a trait.
Heterozygous means 2 different alleles for a trait.
Codominance is when neither allele is dominant so the phenotype is intermediate.
Chromosome Theory of Inheritance says genes are carried from parent to offspring on chromosomes.
Meiosis is a process where chromosome pairs separate into sex cells with half as many chromosomes as
body cells.
Humans have 23 pairs or 46 chromosomes.