Question 45
Chromosomes, DNA and Sex LinkageThe illustration below represents a cross between a colour-blind male and a normal female. Which of the genotypes are carriers of colour blindness?
- A.I and II only
- B.I and III only
- C.II and III only
- D.I, II and III only
Show the answer and explanation
Answer: A (I and II only)
Explanation
I and II are XcX females: they carry one colour-blindness allele but see normally. III and IV are normal XY males.