Vocabulary Chapter 11

My scientific studies have afforded me great gratification; and I am convinced that it will not be long before the whole world acknowledges the results of my work. -Gregor Mendel

Allele

is one of two or more forms of the DNA sequence of a particular gene.

codominance

 refers to a relationship between two alleles of a gene

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 Continous Variation

Of a population, a more or less continuous range of small differences in a given trait among its individuals.

Dihybrid Cross

is a cross between F1 offspring (first generation offspring) of two individuals that differ in two traits of particular interest.

epistasis

Interaction between the products of two or more gene pairs.

F₁

The offspring of the initial genetic cross.

F₂

The offspring of parents that are the first filial generation from a genetic cross

Gene

is a unit of heredity in a living organism.

Genotype 

is the genetic makeup of a cell, an organism, or an individual.

Heterozygous

When cells of diploid organism contain two different alleles of a gene.

Homozygous Dominant  

That it has two dominant alleles.

Homozygous Recessive

A same trait that is not the stronger trait which is dominant.

 Hybrid Offspring

Offspring of crosses between parents with different traits.

Incomplete Dominance

Is a form of intermediate inheritance in which one allele for a specific trait is not completely dominant over the other.

Independent Assortment

States that allele pairs separate independently during the formation of gametes.

Monohybrid Cross

Is a cross between two parents that breed true for different versions of a single trait. 

Multiple Alelle System

A "variation" of a gene.Genes which have more than two alleles

Phenotype

Is any observable characteristic or trait of an organism.

Pleiotropy

Is the condition in which a gene influences the phenotype of more than one part of the body.

Probability 

The chance that each outcome of a given event will occur is proportional to the number of ways the outcome can be reached.

Punnet-square Method

A way to predict probable outcomes of a genetic cross.

Segregation 

States that allele pairs separate during gamete formation, and randomly unite at fertilization.

Testcross

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

True-breeding lineage

Occurs when offspring inherited identical alleles, generation after generation.