Extensions to Mendelian Inheritance

A comprehensive collection of vocabulary flashcards covering key concepts in the study of extensions to Mendelian inheritance.

Complete Dominance

Phenotype of heterozygote is the same as that of the homozygous dominant.

Incomplete Dominance

Phenotype of the heterozygote is a mix between the homozygous phenotypes.

Codominance

Phenotype of the heterozygote exhibits aspects of both homozygous phenotypes.

Multiple Alleles

More than two different forms of a gene, although an individual can possess only two.

Epistasis

Interaction where one gene masks or modifies the expression of another gene.

Pleiotropy

A single gene affects multiple traits.

Polygenic Traits

Traits that are controlled by multiple genes.

Phenotype

The observable characteristics of an organism.

Genotype

The genetic makeup of an organism.

Dominant Allele

An allele that expresses its phenotype in the presence of another allele.

Recessive Allele

An allele that expresses its phenotype only when paired with another recessive allele.

Heterozygous

Having two different alleles for a specific gene.

Homozygous

Having two identical alleles for a specific gene.

Sickle Cell Anemia

A disease in which there is a mutation in the hemoglobin gene, leading to a peculiar shape of red blood cells.

ABO Blood Groups

Blood groups determined by codominance and multiple alleles at the I gene.

Antigen

A substance that induces an immune response, such as on the surface of red blood cells.

Antibody

A protein produced by the immune system that binds specifically to an antigen.

Hydrangea Color Variation

Example of environmental influence on phenotype, where soil pH affects flower color.

Penetrance

The proportion of individuals with a specific genotype that actually express the associated phenotype.

Expressivity

The degree to which a genotype is expressed in the phenotype.

Continuous Variation

Variation in a trait that shows a range of phenotypes, usually controlled by multiple genes.

Discontinuous Variation

Variation in a trait with distinct categories, usually controlled by a single gene.

Quantitative Traits

Traits that show continuous variation and are influenced by multiple genes.

Environmental Influence

The effect of environmental factors on the expression of genetic traits.

Pleiotropic Effects

Multiple effects resulting from a single gene affecting multiple traits.

Incomplete Penetrance

When a dominant allele does not always result in the expected phenotype.

Dominant-Recessive Relationship

The interaction where one allele's phenotype completely masks another's.

Polygenic Inheritance

Inheritance pattern where multiple genes influence a trait.

Overdominance

A phenomenon where heterozygotes have a greater fitness than either homozygote.

Genetic Testing

Analyzing DNA to identify genetic disorders or mutations.

Blood Type Compatibility

Rules that govern which blood types can be safely transfused.

Rh Factor

An antigen present or absent on red blood cells that determines blood type (positive or negative).

Mendelian Genetics

The set of primary principles of genetic inheritance derived from Gregor Mendel.

Gametes

Reproductive cells that carry half the genetic information of an individual.

Punnett Square

A diagram used to predict the genetic outcomes of a cross between two individuals.

Cross Pollination

The transfer of pollen from the flower of one plant to the flower of another.

Inheritance

The genetic transmission of characteristics from parents to offspring.

Phenotypic Ratio

The ratio of different phenotypes observed in the offspring.

Genotypic Ratio

The ratio of different genotypes observed in the offspring.

Homozygous Dominant

An organism with two dominant alleles for a trait.

Homozygous Recessive

An organism with two recessive alleles for a trait.

F1 Generation

The first filial generation in a breeding experiment.

F2 Generation

The second generation, resulting from the self-fertilization or cross-fertilization of the F1 generation.

Wild Type

The most common phenotype or genotype found in nature.

Transgenic Organism

An organism that contains a gene or genes which have been artificially inserted instead of the acquired through reproduction.

Quantitative Trait Loci (QTL)

Sections of DNA which are associated with particular phenotypic traits.

Biotechnology

The application of biological systems and organisms to develop or create different products.

Gene Therapy

A field of medicine that aims to treat or prevent disease by modifying genes.

Genomic Imprinting

A genetic phenomenon by which certain genes are expressed in a parent-of-origin-specific manner.

Heritability

The proportion of variation among individuals in a population that is due to genetic variation.