UNIT 5

Meiosis

The process all organisms undergo to produce gametes, involving one round of DNA replication and two rounds of cellular division, resulting in genetically unique haploid cells.

Homologous Pairs

Chromosomes containing and coding for the same information that find their counterparts during meiosis, contributing to genetic variation.

Crossing Over

The process during meiosis where homologous chromosomes exchange genetic material, enhancing genetic diversity by creating new combinations of genes.

Independent Assortment

The random alignment of chromosomes during meiosis contributes to genetic variation by creating unique combinations of chromosomes in daughter cells.

Random Fertilization

The random chance that each egg and sperm will join one another, leading to genetic diversity as each fertilization results in a unique genetic combination.

Sex-linked Genes

Genes linked to the X and Y chromosomes, affecting traits like color blindness and hemophilia.

Carrier

A female with one X chromosome carrying a recessive sex-linked gene, passing it on without expressing the trait.

Non-Mendelian Genetics

Inheritance patterns not following Mendel's laws, including multiple alleles, sex-linked traits, incomplete dominance, and codominance.

Multiple Alleles

Traits with more than two versions of a gene, like blood type in humans or fur color in rabbits.

Incomplete Dominance

Traits where neither allele is dominant, seen in flower colors resulting in a blend of colors in heterozygous individuals.

Co-dominance

Traits where both alleles are equally dominant, like spots on certain cow breeds, leading to a mix of parental phenotypes in offspring.

Phenotypic Plasticity

Ability of organisms to exhibit different phenotypes in response to environmental changes, aiding in adaptation to variable conditions.

Punnett Squares

Tools used to determine the probability of offspring inheriting specific traits from parents, based on Mendelian genetics and simple inheritance patterns.