Nondisjunction and Mendelian Genetics

These flashcards cover key concepts related to nondisjunction, Mendelian genetics, inheritance patterns, and genetic terminology.

Nondisjunction

Mistake in meiosis that produces gametes with incorrect numbers of chromosomes.

Trisomy 21

A genetic condition caused by an extra chromosome 21, also known as Down syndrome.

Karyotype

An organized picture of an individual's chromosomes used to assess their structure and number.

Genotype

The specific alleles an individual carries for a particular gene.

Phenotype

The observable characteristics or traits of an individual, determined by genotype.

Dominant allele

An allele that is expressed if present, even if paired with a different allele.

Recessive allele

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

Heterozygous

Having two different alleles for a particular gene.

Homozygous

Having two identical alleles for a particular gene.

Mendel's Law of Segregation

The law stating that pairs of alleles separate equally into gametes during meiosis.

Independent Assortment

The process through which alleles of different genes are distributed independently to gametes.

Incomplete dominance

A genetic situation where neither allele is completely dominant, resulting in a blend of traits.

Polygenic inheritance

A type of inheritance where multiple genes control a single trait, such as height or skin color.

X-linkage

The inheritance pattern for genes located on the X chromosome; often related to sex-linked traits in humans.

Pedigree

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

Inbreeding

Mating between close relatives that can increase the chance of offspring inheriting genetic disorders.