Lecture 19: Mendel and the Gene Idea

This set of flashcards covers fundamental vocabulary terms and concepts from Mendelian genetics, providing definitions for key terms and principles related to inheritance and genetic crosses.

True Breeding

Organisms that, when self-pollinated, produce offspring identical to themselves.

Hybridization

The breeding technique that involves crossing two different true-breeding varieties.

Monohybrid Cross

A genetic cross between parents that differ in only one trait.

P Generation

The parental generation in a genetic cross.

F1 Generation

The first filial generation, or the offspring of the P generation.

F2 Generation

The second filial generation, or the offspring of the F1 generation.

Law of Segregation

The principle stating that individuals carry two alleles for each trait, which segregate during gamete formation.

Law of Independent Assortment

The principle stating that alleles for different traits assort independently of one another during gamete formation.

Phenotype

The observable characteristics or traits of an organism.

Genotype

The genetic makeup of an organism, represented by alleles.

Homozygous

An organism that has two identical alleles for a particular trait.

Heterozygous

An organism that has two different alleles for a trait.

Dominant Allele

An allele that expresses its phenotype even in the presence of a recessive allele.

Recessive Allele

An allele that is masked by the presence of a dominant allele.

Test Cross

A breeding experiment used to determine the genotype of an individual with a dominant phenotype.

Allele

Alternative forms of a gene that account for variations in a inherited trait.

Locus

The specific location or position of a gene on a chromosome.

Dihybrid Cross

A genetic cross between parents that differ in two traits.

Blending Inheritance

The hypothesis that offspring are a blend of parental traits, which Mendel's work refuted.

Acquired Characters

Traits that are acquired in an organism's lifetime and supposedly passed on to offspring, discredited by Mendelian genetics.

Punnett Square

A diagram used to predict the outcome of a genetic cross.