Classical Mendelian Genetics Vocabulary

Flashcards on Classical Mendelian Genetics

Genetics

The study of variation and heredity, concerned with the origin, maintenance, and inheritance of variation from generation to generation.

Gregor Mendel

Considered the father of genetics, known for his experiments with pea plants and his laws of inheritance.

Genotype

The genetic constitution (make-up) of an individual, showing the types of alleles present.

Phenotype

The physical appearance or function of an organism resulting from its genotype and environment.

Dominant Allele

An allele that masks (hides) the expression of another allele of the same gene, producing a dominant phenotypic character.

Codominant Alleles

Contrasting alleles that are both expressed in a heterozygote (F1), exhibiting characteristics of both parents.

Incompletely Dominant Alleles

Alleles where a heterozygote exhibits an intermediate phenotype between the two homozygous parental phenotypes.

Recessive Allele

An allele whose effect is masked (hidden) by the presence of a dominant allele of the same gene, only expressed in the homozygous state.

Monohybrid Cross

A cross between homozygous parents that differ only in one pair of alleles of one gene, controlling one character.

F1 Hybrid

The progeny or offspring of a monohybrid cross, also known as the first filial generation.

F2 Generation

The second filial generation, raised by allowing the F1 hybrids to self-pollinate.

Punnet Square

A method devised by R.C. Punnet which clearly shows how the alternative forms of a character combine to produce the F2 progeny.

Testcross

A breeding test in which a dominant phenotype (F1 hybrid) is crossed with the recessive homozygote to verify its genotype.

Backcross

A testcross in which an individual is crossed with one of its own parents.

Law of Independent Assortment

When two or more unlinked pairs of genes are brought together in a cross, their alleles assort (segregate) independently of each other as a result of meiosis.

Dihybrid Cross

A cross involving two pairs of contrasting traits.

Chi-squared test (χ2 Test)

A statistical test used to confirm whether the differences between observed and expected values are significant or not.