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Question: 1. The arctic fox has fifty small chromosomes, and the red fox has thirty-eight larger chromosome...
1. The arctic fox has fifty small chromosomes, and the red fox has thirty-eight larger chromosomes.Hybrids of these two species are sterile, but cytological studies during meiosis in these hybrids reveal both paired and unpaired chromosomes.
A. Account for the sterility of the hybrids.
B. How can you explain the paired chromosomes?
2. Can you devise a method of chromosome partitioning during gamete formation that would not involve synapsis that is,can you reengineer meiosis without passing through a synapsis stage?
3. Given the same information as in problem 0.1, diagram one of the possible meioses. How many different gametes can arise, absent crossing over? What variation in gamete genotype is introduced by a crossover between the A locus and its centromere?
Take note: This is the problem 0.1 to get the answer on number 3 please help.
Problem 0.1 (You are working with a species with 2n 6, in which one pair of chromosomes is telocentric, one pair subtelocentric,and one pair metacentric.The A, B, and C loci, each segregating a dominant and recessive allele (A and a, B and b, C and c),are each located on different chromosome pairs. Draw the stages of mitosis.)
Advance thank you
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Saloni Mendirattaanswered this
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A. Sterility is often associated with the different number of chromosomes that the two species have. The sterile interspecific hybrids cannot generate viable gametes because the additional chromosome cannot make a homologous pair at the stage of meiosis, meiosis becomes disrupted, and fertile ***** or eggs are not constructed.
B. Sterility in a non-polyploid combination is often an outcome of chromosome number; if parents have varying chromosome pair numbers, the offspring will have an odd number of chromosomes, which leaves them incapable to generate chromosomally balanced gametes and the offspring will be infertile.
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