T2L12 Genetic inheritance and meiosis Flashcards
What is a locus
The location of a gene on a chromosome
Define recessive
An allele that only shows its effect on the phenotype when the dominant allele is not present (a recessive allele has been inherited from both parents)
Define dominant heterozygous
When only one of this allele is required to show was the phenotype. E.g Aa will show as phenotype because the dominant A is rpesent
Define gene
A length of DNA that codes for a polypeptide
Define genotype
The type of alleles or genes that an organism has
Define phenotype
The characteristics caused by the genotype or the observable effects of the genotype
Define Heterozygous
When an organism has two different copies of an allele
Define Allele
Version of a gene
Define homozygous
When an organism has two identical copies of a gene
Name two types of genetic ‘tracking’
Punnet square and Pedigree diagram