Genetics Vocabulary
Genetics- the scientific study of heredity.
Heredity- The passing of traits from parents to offspring.
Dominant allele- An allele whose trait always shows up in the organism when the allele
is present.
Recessive allele- An allele that is masked with when a dominant allele is present.
Genes- A segment of DNA on a chromosome that codes for a specific trait.
Genotype-An organism’s genetic makeup, or allele combinations.
Phenotype- An organisms physical appearance, or visible traits.
Homozygous-Having two identical alleles for a trait.
Heterozygous- Having two different alleles for a trait.
Chromosome- A thread like cellular structure that carries the information that controls
inherited characteristics.
DNA-The Genetic material that carries information about the organism and that is passed
from parent to offspring.
Sexual Reproduction- The reproductive process that involves two parents who combine
their genetic material to produce a new organism, which differs from both parents.
Asexual Reproduction- The production of offspring by a single parent, without the
union of a sperm cell and an egg cell.
Reproduction- The process by which living things produce new individuals of the same
type.
Egg- A female sex cell.
Sperm-A male sex cell.
Fertilization- The joining of a sperm cell and an egg cell.
Adaptation- A characteristic that helps an organism survive in its environment and
reproduce.
Species- A group of similar organism whose members can mate with one another and
produce fertile offspring.
Biodiversity- The number of different species in an area.
Extinction- The disappearance of all members of a species from earth.
Nucleus- The central core of an atom containing protons and usually neutrons; also, the
control center of the cell that directs the cells’ activities and determines the cell’s
characteristics.
Hybrid- An organism that has two different alleles for a trait; an organism that is
heterozygous for a particular trait.
Purebred- An organism that always produces offspring with the same form of traits as
itself.
Inherited Trait- An offspring’s phenotype inherited by its parents. (Having red hair)
Acquired Trait- A trait that is learned. (How to make pizza)
Selective Breeding- The process of selecting a few organisms with desired traits to serve
as parents of the next generation.