Ch 3.1 Monohybrid and Dihybrid Crosses Flashcards

Gene

A unit of heredity that is transferred from a parent to offspring and determines some characteristic of the offspring.

Allele

Different versions of a gene that determine a specific trait.

Genotype

The genetic constitution of an individual, specifically the alleles it possesses.

Phenotype

The physical expression or characteristics of a genotype.

Homozygous

Having two identical alleles for a particular gene.

Heterozygous

Having two different alleles for a particular gene.

Dominant vs Recessive

Dominant alleles express their traits even in heterozygous conditions, while recessive alleles express their traits only in homozygous conditions.

Law of Segregation

Mendel's first law stating that the two alleles for a gene segregate from each other during gamete formation.

Law of Independent Assortment

Mendel's second law stating that alleles for different genes assort independently of one another in gamete formation.

Monohybrid cross

A cross between individuals that involves one pair of contrasting traits.

Dihybrid cross

A cross between individuals that involves two pairs of contrasting traits.

Probability of offspring phenotype

The likelihood that offspring will exhibit a certain phenotype based on parental genotypes.

Independent Assortment

The principle that genes for different traits are inherited independently of each other.

Gamete

A reproductive cell (sperm or egg) that carries a single set of chromosomes.

Tetrahybrid

An organism that is heterozygous for four different genes.