18. The diagram below shows spermatogenesis (on the left) a…
18. The diagram below shows spermatogenesis (on the left) and oogenesis (on the right) followed by a fertilization event. The numbered circles are cells. The long purple bars in the cells are X chromosomes while the short blue bars in the cells are Y chromosomes. Cell #8 is the zygote resulting from fertilization. a. Where has the non-disjunction occurred? Use the number to the upper left of the cell to help you explain the location of the non-disjunction. b. What non-disjunction syndrome does this illustration demonstrate? How do you know?
Read Details13. The roseatte spoonbill is a bird that lives in mangrove…
13. The roseatte spoonbill is a bird that lives in mangrove marshes and captures insects with a long spoon-shaped bill. Bill color is due to a gene that has two incompletely dominant alleles. Individuals that are homozygous for one allele have a black bill. Individuals that are homozygous for the other allele have a bill that is almost white. What color bill will heterozygous individuals most likely express? Explain the reasoning/rationale behind your answer.
Read Details16. The illustration below shows a chromosome on which the…
16. The illustration below shows a chromosome on which the loci (locations) of 4 linked alleles (a, B, C, and d) have been mapped. Which two alleles are least likely to be “unlinked” during crossing over? Why did you pick these two alleles?
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