Anatomy & Physiology II: Heredity II

A set of vocabulary flashcards covering the concepts of inheritance, genetic expression, and hereditary tools based on the lecture notes.

Simple Dominance Inheritance

Reflects the interaction of dominant and recessive alleles where one allele can mask the expression of another.

Punnett square

A tool used to represent genetic crosses that helps predict possible gene combinations resulting from the mating.

Dominant allele

Represented by a capital letter, these alleles usually encode functional proteins and are expressed if at least one is present.

Recessive allele

Represented by a lowercase letter, these alleles often encode defective proteins or no protein at all and are only expressed when the genotype is homozygous.

Homozygous

A condition where an individual has two identical alleles for a specific gene (e.g., $TT$ or $tt$).

Heterozygous

A condition where an individual has two different alleles for a specific gene (e.g., $Tt$).

Huntington’s disease

A condition caused by a delayed-action dominant gene.

Multiple-Allele Inheritance

Inheritance involving genes that exhibit more than two allele forms, such as the three alleles ($I^A$, $I^B$, $i$) that determine ABO blood types.

Codominant

A type of inheritance where both alleles are expressed if present, such as alleles $I^A$ and $I^B$ in the ABO blood grouping.

Sex-Linked Inheritance

Inherited traits determined by genes on the sex chromosomes, where the X chromosome carries over 2500 genes and the Y carries approximately 80 genes.

Polygenic Inheritance

A pattern of inheritance where several different genes act in concert to produce a trait, resulting in fine-scale phenotypic variation such as skin color, eye color, and height.

Phenocopies

Environmentally produced phenotypes that mimic conditions caused by genetic mutations.

Small RNAs

Includes microRNAs (miRNAs) and short interfering RNAs (siRNAs) that bind to mRNAs and cause them to be destroyed or not translated into proteins.

Extranuclear (Mitochondrial) Inheritance

The transmission of 37 genes found in human mitochondrial DNA ($mtDNA$) which are transmitted by the mother in the cytoplasm of the egg.

Pedigrees

Charts used to trace a particular genetic trait through several generations to help predict its future occurrence.

Carrier Recognition

The process of identifying individuals who carry a recessive gene for a disorder using pedigrees and DNA testing.