Genetics and Heredity Lecture Notes

These flashcards cover important vocabulary terms related to genetics and heredity, including definitions and key concepts introduced in the lecture.

Genetics

The study of heredity and the variation of inherited characteristics.

Pangenesis

An early theory suggesting that each body part contributes information to reproductive organs through gemmules.

Mendel's Law of Segregation

During meiosis, the two alleles for a specific gene segregate so that each gamete receives only one allele for that trait.

Heterozygote

An individual possessing two different alleles at a locus.

Phenotype

The observable physical properties of an organism; it's appearance.

Dihybrid Cross

A genetic cross between two individuals who are heterozygous for two traits.

Epistasis

A type of gene interaction where the effect of one gene is suppressed or masked by another gene.

Complete Dominance

A condition where the phenotype of a heterozygote is indistinguishable from that of the homozygous dominant.

Codominance

A genetic scenario where both alleles in a heterozygote are fully expressed.

Allele

One of two or more alternative forms of a gene that arise by mutation.

Allelic Frequencies

Proportions of different alleles in a population.

Hardy-Weinberg Principle

A principle stating that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of evolutionary influences.

Null Hypothesis

A statistical hypothesis that assumes no significant difference from the expected outcome.

Chi-Square Test

A statistical test used to determine if the observed frequencies of events differ from expected frequencies.

Mutations

Changes in the DNA sequence of an organism's genome.

Homozygote

An individual organism possessing two identical alleles at a locus.

Gene Pool

The combined genetic information of all members of a particular population.

Testcross

A cross between an individual with an unknown genotype and a homozygous recessive individual.

Quantitative Traits

Traits that are measured on a continuous scale; typically polygenic.

Mitosis

The process of cell division resulting in two genetically identical daughter cells.

Meiosis

A type of cell division that reduces the chromosome number by half, producing four haploid cells.