Chapter 14 - Mendel and the Gene Idea

Flashcards covering key concepts and terms related to Mendel's principles of genetics.

Gregor Mendel

Austrian monk who discovered the basic principles of heredity through experiments with pea plants.

Gene

A hereditary determinant for a trait.

Allele

Different versions of a gene responsible for variation in traits.

Genotype

The combination of alleles found in an individual.

Phenotype

The observable features of an individual.

Homozygous

An individual with two copies of the same allele.

Heterozygous

An individual with two different alleles.

Dominant allele

An allele that exerts its effect whenever present.

Recessive allele

An allele that is masked if a dominant allele is also present.

Principle of Segregation

The principle stating that two members of each gene pair separate into different gamete cells during the formation of sperm and eggs.

Independent Assortment

The principle stating that alleles of different genes are transmitted independently of each other.

Pedigree Analysis

A diagram that shows the occurrence of a genetic trait in several generations of a family.

Multiple Alleles

More than two forms of a gene exist in a population, like ABO blood types in humans.

Codominance

A genetic scenario in which both alleles in a heterozygote are fully expressed.

Incomplete Dominance

A condition where heterozygous individuals display a blend of both traits.

Pleiotropy

The phenomenon where one gene influences multiple traits.

Polygenic Traits

Traits that are influenced by multiple genes.

Gene-Environment Interaction

The combined effect of genes and environment on phenotype.

Epistasis

Interaction between genes whereby one gene affects the expression of another gene.

Autosomal Trait

A trait determined by genes located on non-sex chromosomes.

X-Linked Trait

A trait associated with a gene located on the X chromosome.

Autosomal Recessive

A trait that requires two recessive alleles for expression.

Autosomal Dominant

A trait expressed with only one copy of a dominant allele.

X-Linked Recessive

A trait carried on the X chromosome that affects males primarily.

X-Linked Dominant

A trait carried on the X chromosome that affects both males and females.