Question 7
FIn fruit flies, the allele for normal wings, NNN, is dominant to the allele for vestigial wings, nnn. Vestigial wings are small and cannot be used for flying.
Two fruit flies with normal wings were crossed.
The Figure shows the number of offspring with each type of wing.
Figure
a.[1]
Use the Figure to give the number of offspring with vestigial wings.
b.[2]
Calculate the percentage of the offspring that had normal wings.
c.[3]
Deduce the genotypes of the two parent fruit flies. Explain your answer.
d.[1]
One offspring with normal wings is chosen at random.
State the probability that this offspring is heterozygous.
3.3 Inheritance Questions
43 exam-style questions on Edexcel GCSE Biology 3.3 Inheritance, covering 3.3.1 Gregor Mendel and the basis of genetics, 3.3.2 Alleles and inherited characteristics, 3.3.3 Monohybrid inheritance, 3.3.4 Determination of sex at fertilisation, 3.3.5 Outcomes from monohybrid crosses, 3.3.6 Inheritance of ABO blood groups, 3.3.7 Inheritance of sex-linked disorders, and 3.3.8 Multiple genes and phenotypic features. Each one has a worked solution and a mark scheme showing where the marks go.