Concept explainers
A crossover has occurred in the bivalent shown here.
What is the outcome of this single crossover event? If a second crossover occurs somewhere between A and C, explain which two chromatids it would involve and where it would occur (i.e., between which two genes) to produce the chromosomes shown here:
A.
B.
C.
D.
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Genetics: Analysis and Principles
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- Asaparrow_forwardConsider the following two meiocytes in metaphase I, with crossover positions as indicated for cell A. Solid black lines indicate spindle microtubules. Assume blue chromosomes represents paternal chromosomes and green maternal chromosomes. F G N R A B D e g a B d E Cell A Cell B i) How many chromosomes and chromatids were present in cell A during the G1 phase? Please clearly specify chromosomes and chromatids in your answer. ii) For cell A, list all the gametes that will be produced from this cell. Give the alleles of each gamete contained within a set of brackets. You may ignore independent assortment. iii) For cell B, list all the gametes that will be produced from this cell given independent assortment. Give the alleles of each gamete contained within a set of brackets. You may assume that no crossing over would take place.arrow_forwardAn individual is heterozygous for a reciprocal translocation, with the following chromosomes: A • B C D E F A • B C V W X R S T • U D E F R S T • U V W X a. Draw a picture of these chromosomes pairing in prophase I of meiosis. b. Draw the products of alternate, adjacent-1, and adjacent-2 segregations. c. Explain why the fertility of this individual is likely to be less than the fertility of an individual without a translocation.arrow_forward
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