B5.1.4 - Dominant And Recessive Alleles Flashcards
What is an allele?
Different form of a gene
What is a dominant allele?
An allele where only one is needed to define a characteristic of a person
Give an example of a dominant allele
Brown eyes
Give an example of a recessive allele
Blue eyes
If both parents had blue eyes, what colour would the child’s eyes be?
Blue
If both parents had brown eyes, what colour would the child’s eyes be?
Brown
If one parent has brown eyes and another has blue eyes, what colour would the child’s eyes be?
Brown, because it is the dominant allele
How would you represent a dominant allele in letter form?
Capital letter
How would you represent a recessive allele in letter form?
Lower case letter
How many genotypes are there for eye colour?
3
What does it mean if a person has a heterozygous characteristic?
They have 2 different forms of genes
What does it mean if a person has a homozygous characteristic?
The person has the same form of gene
Which allele would you write first in letter form?
Dominant
What is homozygous dominant?
When both alleles of a characteristic are dominant
What is homozygous recessive?
When both forms of a gene are recessive
