Chapter 12: Mendel & Heredity

This set of flashcards covers fundamental concepts and terminology related to Mendelian genetics and heredity, as discussed in the lecture notes.

Alleles

Different forms of a gene that can exist at a specific locus.

Genotype

The specific genetic makeup of an organism, comprising the alleles inherited from its parents.

Phenotype

The observable physical or biochemical characteristics of an organism, determined by its genotype.

Test Cross

A cross between an organism with an unknown genotype and a homozygous recessive organism to determine the genotype of the former.

Dihybrid Cross

A genetic cross involving two traits, where each trait is governed by different genes.

Law of Segregation

The principle that during gamete formation, the two alleles for a trait separate into different gametes.

Law of Independent Assortment

The principle stating that alleles for different traits segregate independently from one another during the formation of gametes.

Codominance

A relationship between two alleles of a gene, where both alleles are fully expressed in a heterozygote.

Incomplete Dominance

A genetic situation where one allele does not completely dominate another, resulting in a phenotype that is a blending of both alleles.

Pleiotropy

A phenomenon where one gene influences multiple phenotypic traits.

Polygenic Inheritance

A form of inheritance in which multiple genes independently affect a single trait.

Epistasis

A interaction where one gene can mask or alter the phenotypic expression of another gene.

Sex-linked Traits

Traits that are determined by genes located on the sex chromosomes.

Lethal Alleles

Alleles that may cause the death of an organism when present in a certain genotype.

Pedigree Analysis

A diagram that depicts the lineage or descent of an individual and is used to analyze genetic disorders.

Mendel's Model

Mendel’s theories on inheritance, which include the concepts of alleles, dominance, segregation, and independent assortment.