Inheritance Flashcards
Gene
A sequence of bases on a DNA molecule that codes for a protein (polypeptide) which results in a characteristic.
Allele
One or more alternative versions of the same gene.
Genotype
The genetic constitution of an organism. The alleles it has.
Phenotype
The expression of the genetic constitution and its interaction with the environment. Characteristics.
Dominant
An allele whose characteristic appears in the phenotype even when there is only one copy.
Recessive
An allele whose characteristic only appears in the phenotype if two copies are present.
Codominant
Alleles that are both expressed in the phenotype. Neither one is recessive.
Locus
The fixed position of a gene on a chromosome. Alleles are found at the same locus on each chromosome in a pair.
Homozygous
An organism that carries two copies of the same allele. BB or bb.
Heterozygous
An organism that carries two different alleles. Bb.
Monohybrid inheritance
Inheritance of a single characteristic controlled by different alleles.
Genetic pedigree diagrams show:
How traits run in families.
Carrier
A person carrying an allele which is not expressed in the phenotype but that can be passed onto offspring.
Sex linked gene
When the allele that codes for a characteristic is located on the sex chromosome.
