Topic 7A - Genetics Flashcards
What is a gene?
A sequence of bases on a DNA molecule that codes for a protein which results in a characterisitc
What is an allele?
Different versions of the same gene
What is a genotype?
Different alleles an organism has
What is a phenotype?
What characteristics an organism has as as result of its genes and the effect of environment
What is the dominant allele?
The allele that is expressed
What is the recessive allele?
The allele which isn’t expressed unless there is 2 of them
What are codominant allleles?
Both alleles are expressed
What is Monohybrid inheritance?
The inheritance of a characteristics controlled by a single gene
What do Monohybrid crosses show?
Likelihood of the different alleles of the gene being inherited by the offspring
What is Dihybrid inheritance?
Inheritance of 2 characteristics which are controlled by different genes. Each of the 2 genes will have different alleles
What can Dihybrid crosses be used to show?
Dihybrid crosses can be used to show the likelihood of offspring inheriting certain combinations of the two characteristics from particular parents
What is an autosome?
Any chromosome that isn’t a sex chromosome
What is Epistasis?
Where many different genes can control the same characteristic
