Take the 2-minute tour ×
Biology Stack Exchange is a question and answer site for biology researchers, academics, and students. It's 100% free, no registration required.

A female genotype, shown as abc / +++ produces 100 meiotic tetrads. Among these, 68 showed no cross over (NCO) events; 20 showed single crossover (SCO1) between a and b; 10 showed single crossover between b and c (SCO2) and 2 showed a double crossover (DCO) between a and b and between b and c. Of the 400 gametes produced, how many will be of the following types? - NCO, SCO1,SCO2 and DCO.

My answers : 272,80,40,8

share|improve this question
I think there is something missing from the question. "how many will be of the following types?" What types? –  kmm Feb 4 at 17:14
This appears to be a question from the Klug-Cummings Essentials of Genetics, only there it asks "how many of each of the 8 different genotypes will be produced?" Are you sure that's not your question? –  Jonathan Van Matre Feb 11 at 19:20

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.