Revise: Variation and inheritanceSummary of inheritance terms

The phenotype for a characteristic like eye colour is the result of the combination of alleles. If the alleles in the parental genotype are dominant or recessive, probable outcomes can be predicted.

Part ofBiologyRevision guides: Multicellular organisms

Summary of inheritance terms

Genetics

TermDefinition
AllelesDifferent forms of a gene that produce different phenotypes
DominantAn allele that always produces a certain phenotype in an organism. It is represented by a capital letter.
GeneA sequence of DNA on a chromosome that contains coded instructions for making a specific protein
GenotypeAn individual's alleles for a particular characteristic
HeterozygousDescribes an individual who has inherited two different alleles of the same gene from their parents
HomozygousDescribes an individual who has inherited the same allele for a gene from their parents
PhenotypeThe outward appearance resulting from an individual's genotype for a particular characteristic
RecessiveAn allele whose effect on the phenotype can be masked by a dominant allele of the same gene. It is represented by a lower case letter.
TermAlleles
DefinitionDifferent forms of a gene that produce different phenotypes
TermDominant
DefinitionAn allele that always produces a certain phenotype in an organism. It is represented by a capital letter.
TermGene
DefinitionA sequence of DNA on a chromosome that contains coded instructions for making a specific protein
TermGenotype
DefinitionAn individual's alleles for a particular characteristic
TermHeterozygous
DefinitionDescribes an individual who has inherited two different alleles of the same gene from their parents
TermHomozygous
DefinitionDescribes an individual who has inherited the same allele for a gene from their parents
TermPhenotype
DefinitionThe outward appearance resulting from an individual's genotype for a particular characteristic
TermRecessive
DefinitionAn allele whose effect on the phenotype can be masked by a dominant allele of the same gene. It is represented by a lower case letter.
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