Mendelian and Quantitative Genetics

These flashcards cover fundamental concepts in Mendelian and Quantitative Genetics, providing definitions and key terms necessary for understanding genetics inheritance and variation.

Mendelian Genetics

The study of how genes are inherited according to the principles set forth by Gregor Mendel.

Quantitative Genetics

A field of genetics that deals with phenotypes that vary continuously and are influenced by multiple genes and environmental factors.

Homozygous

An organism that has two identical alleles for a gene.

Heterozygous

An organism that has two different alleles for a gene.

Phenotype

The physical appearance of an individual determined by their genotype.

Genotype

The genetic makeup of an individual; the combination of alleles for a particular gene.

Alleles

Different versions of a gene that may produce distinguishable traits.

Punnett Square

A grid used to predict the genetic outcomes of a cross between two organisms.

Dominant allele

An allele that masks the effect of the other allele when present.

Recessive allele

An allele that is masked by the presence of a dominant allele.

Codominance

A situation in which both alleles in a heterozygote contribute to the phenotype.

Incomplete Dominance

A genetic situation where one allele does not completely dominate another, resulting in a new phenotype.

Pleiotropy

The ability of a single gene to influence multiple phenotypic traits.

Epistasis

A phenomenon where a gene at one locus interferes with the expression of a gene at another locus.

Polygenic traits

Traits that are controlled by multiple genes, leading to a continuous range of phenotypes.

Meiosis

A type of cell division that reduces the chromosome number by half, resulting in gametes.

Gametes

Reproductive cells (sperm and eggs) that carry half the genetic information of an organism.

Zygote

A fertilized egg that results from the fusion of two gametes.

Genetic Variation

Differences in DNA sequences among individuals, which can lead to different traits.

Genetic Counseling

A process to evaluate and understand genetic disorders and the likelihood of their occurrence in offspring.

Environmental Influence

The effect of external factors on an organism's phenotype, modifying the expression of genes.

Mendelian Ratio

The expected ratio of phenotypes that arise from a genetic cross, often seen in simple dominant/recessive traits.