Unit 5: Heredity

AP Biology Unit 5

Meiosis

The process that ensures the formation of haploid gamete cells in sexually reproducing diploid organisms.

Diploid

A cell containing two full sets of chromosomes, represented by 2n.

Haploid

A cell containing one set of chromosomes, represented by n.

Crossing Over

The exchange of genetic information between non-sister chromatids during prophase 1 of meiosis, increasing genetic diversity.

Law of Segregation

States that the two alleles for each trait segregate during the formation of gametes.

Independent Assortment

Different genes independently separate from one another when reproductive cells develop.

Phenotypic Plasticity

The ability of one genotype to produce more than one phenotype based on environmental factors.

Nondisjunction

The failure of chromosome pairs to separate properly during cell division, potentially leading to genetic disorders.

Random Fertilization

The concept that any genetically unique sperm can join with any genetically unique egg to form a zygote.

Genetic Variation

Differences in genetic traits among individuals in a population, caused by processes such as meiosis, fertilization, and mutations.