Definitions Flashcards
Allele
A version of a gene
Allele frequency
The number of times an allele appears within a population’s gene pool
Autosomal linkage
When two or more genes are positioned on the same autosome. They are unlikely to be separated by crossing over during meiosis so are often inherited together.
Autosome
A chromosome that is not an X or Y chromosome
Co-dominant
When both alleles for a gene in a heterozygous organism equally contribute to the phenotype.
Dihybrid inheritance
The inheritance of two different genes, that determine two phenotypes, on two different chromosomes
Diploid
Describes a cell with a nucleus containing two sets of chromosomes
Dominant
Describes an allele that is always expressed. Represented by a capital letter
Epistasis
Describes a relationship between genes where the allele of one gene affects the expression of a different gene
Gene
A length of DNA on a chromosome that codes for the production of one or more polypeptide chains and functional RNA
Gene pool
All of the different versions of genes (alleles) in the individuals that make up a population
Genotype
An organism’s genetic composition. Describes all alleles
Heterozygous
When someone has two different alleles of a gene
Homozygous
When someone has two identical alleles of a gene
Locus
The position of a gene on a chromosome
