Modern Understandings of Inheritance

These flashcards cover key concepts related to inheritance and genetics, including terminology, theories, and types of mutations.

Chromosome

Threadlike nuclear structures consisting of DNA and proteins that serve as repositories for genetic information.

Linked genes

Genes that are located close together on the same chromosome and tend to be inherited together.

Recombination frequency

The frequency with which a single chromosomal crossover will take place between two genes during meiosis.

Non-disjunction

The failure of homologous chromosomes or sister chromatids to separate during meiosis, resulting in an abnormal chromosome number.

Chromosomal Theory of Inheritance

The theory proposing that traits are carried on chromosomes which occur in matched maternal and paternal pairs that segregate in meiosis.

Sex-linked traits

Traits that are associated with genes found on sex chromosomes, such as the X or Y chromosomes.

Punnett Square

A diagram used to predict the outcome of a genetic cross by considering all possible combinations of gametes.

Mutations

Changes in the DNA sequence that can lead to alterations in phenotype.

Deletion mutation

A chromosomal alteration in which a segment of the chromosome is removed.

Translocation mutation

The transfer of a segment of DNA from one chromosome to another, nonhomologous chromosome.

Trisomy 21

A genetic disorder caused by the presence of an extra chromosome 21, commonly known as Down syndrome.

CRI-DU-CHAT syndrome

A genetic disorder caused by a deletion of a portion of chromosome 5, leading to various developmental issues.

Centimorgan (cM)

A unit of genetic length that represents a 1% chance of recombination occurring between two genes.

Chromosomal abnormalities

Changes in chromosome number or structure that can have significant effects on growth, development, and health.

Pericentric inversion

A chromosomal inversion that includes the centromere.

Paracentric inversion

A chromosomal inversion that does not include the centromere.

Wild type allele

The typical form of a gene as it occurs in nature, which is usually dominant over mutant alleles.