Patterns of Inheritance

Comprehensive vocabulary flashcards covering basic genetics, Mendelian laws, inheritance patterns, and human genetic disorders based on the lecture transcript.

Genetics

The study of heredity or how traits are passed from parents to offspring.

Traits

Distinguishing qualities or characteristics.

Mendel

A 19th Century monk who studied traits in pea plants and is known as the Father of Genetics.

True-breeding plant

A plant that, when self-fertilized, only produces offspring with the same traits.

Monohybrid cross

A cross between two true-breeding plants that differ in only one trait.

P generation

The parental generation consisting of the cross pollination between two true-breeding plants that differ in a particular trait.

F1 (First Filial) generation

The offspring of two different true-breeding varieties; also known as hybrids.

F2 (Second Filial) generation

The offspring produced by self-fertilization of $F_1$ plants.

Genes

The modern name for Mendel’s "factors" that determine traits.

Alleles

Alternative forms of genes.

Homozygous

A condition where the two alleles for a trait are the same.

Heterozygous

A condition where the two alleles for a trait are different.

Dominant

The trait that shows in a heterozygous individual.

Recessive

The trait that is hidden in a heterozygous individual.

Principle of Segregation

Mendel's principle stating that the two alleles for a trait segregate during gamete formation.

Punnett Square

A diagram that shows possible outcomes of a genetic cross.

Genotype

The genetic make up or combination of alleles, such as $PP$, $Pp$, or $pp$.

Phenotype

The observable trait of an organism, such as purple or white flowers.

Testcross

A cross that breeds an individual with an unknown genotype but dominant phenotype with a homozygous recessive individual.

Principle of Independent Assortment

Mendel's principle stating that during gamete formation, a particular allele for one trait can be paired with either allele of another trait.

Dihybrid cross

A cross involving organisms that differ in two traits, illustrating the Principle of Independent Assortment.

Intermediate Inheritance

A pattern where heterozygotes have a phenotype that is intermediate to the phenotypes of the two homozygotes (e.g., Red + White = Pink).

Codominance

A situation where heterozygotes fully express both alleles, such as a flower expressing both red and white color patterns.

Multiple Alleles

A case where several alleles for a trait exist in a population, such as human blood types, though an individual only inherits two.

Polygenic traits

Traits determined by more than one gene pair, such as human height and skin color.

Genetic linkage

The tendency for the alleles on one chromosome to be inherited together.

Gene locus

The specific location where the alleles of a gene reside on homologous chromosomes.

Crossing over

The exchange of genetic material between homologous chromosomes that can recombine genes.

Genetic Duplication

A type of chromosome damage where part of a chromosome is repeated.

Genetic Deletion

A type of chromosome damage where part of a chromosome is removed.

Genetic Inversion

A type of chromosome damage where part of a chromosome is reversed.

Genetic Translocation

A type of chromosome damage where part of one chromosome is moved to another chromosome.

Nondisjunction

An event occurring when chromosomes do not separate during Meiosis, resulting in gametes with extra or missing chromosomes.

Barr Body

A highly condensed and inactive X chromosome in female mammals.

Pedigrees

Family trees that trace the occurrence of a trait within a family.