Patterns of Inheritance: Monohybrid Cross

Flashcards covering the vocabulary and concepts of Mendelian genetics, inheritance theories, and monohybrid crosses based on lecture notes.

Pangenesis

The first theory proposed by Aristotle suggesting every part of the body sends tiny particles into sperm or eggs which get together to form a baby.

Pangenes

Tiny particles described in Aristotle's theory of pangenesis that are sent from body parts like the arms or eyes into sperm or eggs.

Epigenesis

The idea by Leeuwenhoek that a tiny, fully formed human lived inside a sperm head and the mother just provided a place for it to grow.

Blending theory

Darwin's idea that sperm and egg mixed together, resulting in offspring receiving a blend of parent characteristics.

Gametes

Sex cells associated with reproduction in the context of early inheritance theories.

Gregor Mendel

Known as the ‘Father of Modern Genetics,’ he was a botanist in the mid 1800’s who analyzed more than $28,000$ pea plants.

Trait

A specific characteristic or feature of an organism, such as the flower colour of a plant.

True Breeding

Organisms that exhibit the same traits, generation after generation.

Parent generation (P generation)

The organisms initially crossed in breeding, which are typically true breeding.

Cross

The fertilization of a female gamete of specific genetic origin with a male gamete of specific genetic origin.

F1 generation

The offspring produced from a cross of the P generation.

F2 generation

The second generation of offspring, produced by crossing the F1 generation.

Monohybrid cross

A cross of two individuals that differ by only one trait.

Law of Segregation

States that alleles segregate into each of the gametes of the parents during meiosis so that each gamete contains one allele; upon fertilization, offspring contain one allele from each parent.

Alleles

Different forms of a gene; diploid organisms possess two of these for each gene.

Dominant

The form of a trait that always appears when an individual has an allele for it; often designated with a capital letter (e.g., $Y$).

Recessive

The form of a trait that only appears when an individual has two alleles for it; designated with a lowercase letter (e.g., $y$).

Genotype

The combination of alleles for any given trait, or the organism’s entire genetic makeup.

Phenotype

The physical and physiological traits of an organism.

Homozygous

An organism that has two identical alleles of a gene, also referred to as "pure."

Heterozygous

An organism that has two different alleles of a gene, also referred to as "hybrid."

Punnett Square

A tool used to show the various combinations of alleles that result when two parents mate.

Complete Dominance

A condition where one allele is always dominant over the other, completely masking the recessive allele.