Genetics and Inheritance Vocabulary Flashcards

Vocabulary flashcards covering foundational genetics concepts, Mendelian inheritance, crosses, mutations, and non-Mendelian patterns based on the lecture notes.

Genotype

The alleles an organism carries for a gene.

Phenotype

The observable trait that results from an organism's genotype and environment.

Alleles

Alternative versions of a gene, found at the same locus on homologous chromosomes.

Homozygous

Having two identical alleles for a specific gene.

Heterozygous

Having two different alleles for a specific gene.

Dominant allele

An allele that is expressed when only one copy is present.

Recessive allele

An allele that is only expressed when two copies are present.

Carrier

A heterozygous individual who carries a recessive allele but shows the dominant phenotype.

Monohybrid cross

A genetic cross that tracks one gene.

Test cross

Crossing an organism showing a dominant phenotype with a homozygous recessive organism to determine whether the dominant parent is homozygous or heterozygous.

Mendel's law of segregation

The law stating that each individual carries two alleles for each gene, which separate during gamete formation (meiosis) so each gamete receives only one allele.

Dihybrid cross

A genetic cross that tracks two genes at once.

Law of independent assortment

The law stating that alleles of different genes are inherited independently of each other, provided the genes are on different chromosomes or far apart on the same chromosome.

Linked genes

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

X-linked genes

Genes located specifically on the X chromosome.

Pedigree

A family tree showing the inheritance pattern of a trait across generations.

Codominance

An inheritance pattern where both alleles are fully expressed in the heterozygote without blending.

Incomplete dominance

An inheritance pattern where the heterozygote displays a blended intermediate phenotype.

Gene (point) mutations

Changes affecting a single gene, including substitutions (silent, missense, nonsense) as well as insertions and deletions that cause frameshifts.

Chromosomal mutations

Changes to whole chromosomes or large segments, including deletion, duplication, inversion, and translocation.

Aneuploidy

A condition characterized by an extra or missing chromosome, resulting from non-disjunction during meiosis.

Mutagens

Environmental agents, such as radiation or specific chemicals, that increase the mutation rate.