Lecture 7 Vocabulary (BIOL211)

Flashcards covering essential vocabulary and concepts from Mendelian genetics for exam preparation.

character

An observable, physical, heritable feature of an organism that varies among individuals.

trait

The specific alternative forms of a character (e.g., hair color: brown, red, black, blonde).

dominant allele

An allele that masks the effect of a recessive allele in a heterozygous organism.

recessive allele

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

law of segregation

During the formation of gametes, the two alleles responsible for a trait separate from each other.

homozygous

A diploid individual with two identical alleles at a locus (e.g., PP or pp).

heterozygous

A diploid individual with two different alleles at a locus (e.g., Pp).

Punnett square

A diagram that predicts the genotype and phenotype combinations of a genetic cross.

test cross

A cross between an individual displaying a dominant trait and a homozygous recessive individual to determine if the dominant is homozygous or heterozygous.

law of independent assortment

Genes for different traits assort independently of one another in the formation of gametes.

true-breeding

Organisms that, when mated with each other, always produce offspring displaying the same trait.

monohybrid cross

A cross between two individuals focusing on one trait.

dihybrid cross

A cross between two individuals that differ in two traits.

allele

One of two or more alternative forms of a gene.

phenotype

The physical appearance or observable traits of an organism.

genotype

The genetic makeup of an organism.

probability

The likelihood of a specific outcome occurring in a given event.

independent events

Outcomes where the occurrence of one does not affect the occurrence of the other.

multiplication rule

To calculate the probability of two independent events occurring together, multiply their individual probabilities.

addition rule

To calculate the probability of one outcome or another occurring, sum their individual probabilities.