Genetics Vocabulary

Front 1

Alleles

Back 1

any of the alternate forms of a gene that occurs at a specific place on a chromosome, different varieties of genes.

Front 2

Homozygous

Back 2

organisms that contain two of the same alleles for a gene (or trait) at the same location on homologous chromosomes.

Front 3

Heterozygous

Back 3

organisms that have two different alleles for a gene (or trait) at the same location on homologous chromosomes

Front 4

Dominant

Back 4

an allele that is expressed when two different alleles are present in an organism’s genotype. They are represented by capital letters.

Front 5

Recessive

Back 5

an allele that is not expressed unless two copies are present in an organism’s genotype. It is carried and may be passed to offspring. They are represented by lowercase letters.

Front 6

Genotype

Back 6

The actual genetic combination of alleles of an organism.

Front 7

Phenotype

Back 7

The form of a trait that an organism physically displays.

Front 8

Punnett Square

Back 8

A model and tool for predicting all possible genotypes resulting from a cross.

Front 9

Law of Segregation

Back 9

Mendel’s law that states that organisms receive two copies of each gene, one from each parent, and organisms donate only one copy of each gene randomly in their gametes.

Front 10

Monohybrid cross

Back 10

a cross in which only one trait is studied.

Front 11

Dihybrid cross

Back 11

a cross that can be used to study two traits.

Front 12

Law of Independent Assortment

Back 12

Mendel’s law stating that allele pairs separate from one another independently during gamete formation.

Front 13

Law of Dominance

Back 13

Mendel’s law that states that the dominant allele will prevent the expression of a recessive allele.