Activity Section 3 Biol 352 Spring 2018 e. Fill in this branching diagram with t

Question

Activity Section 3 Biol 352 Spring 2018 e. Fill in this branching diagram with the probabilities of recombination during gamete formation. The starting genotype in the first box: write down the three genes on cach chromosome, in order, and with the appropriate dominance. Then fill in all the ovals with the recombination probabilities. Work left to right in the remainder of the boxes to determine the chromosome composition after recombination. x50% Total tee combined x50% x50% . 1. 2. New chromosome x50% = 4. same chromsome set) Two haploid wite the 3 genes in order) same chromsome x50% 7. same chromsome What are the combined probabilities of generating each of the 8 haploid gametes that you have written in the last column? Those can be calculated by multiplying the two probabilities (in ovals) that to that gamete. Write those in the right margin of the diagram. f. Compare your calculations with others at your table. 34

Explanation / Answer

Ans. to complete the figure above lets take an example of pea plant.The dominant characters in pea plant can be round shape of seed, smooth texture of seed and yellow colour of pod.So we can write as

Dominant characters:Round,smooth and yellow(RRSSYY) should be written on one chromosome eg black one

Reccesive characters:Wrinkled, rough and green(rrssyy) should be written on other chromosome eg white one.

The genes will assort independently as the law of independent assortment says.let A be round gene R.so one chromosome will have R gene while other chromosome on the same loci will have winkled gene i.e. a.Like wise for other two genes.So B is Smooth b is rough.C is yellow and c is green.

Suppose recombination probability between A and B is 25% because they are close to each other.SO probability of no recombination is 75%.

If recombination occurs between A and B gene then new set of chromosome can have A b or a B gene on single strand.recombiantion between B and C can be again 25%since B and C are close.Then new set can be A B c or a BC etc.The probablity of no recombination between B and C is 75% then gene allignemntcan be A bC or aBC.

looking at the probability of no recombination between A nd B the new chromosome will be A and B on single sister chromatid.Probalityof recombination between B and C is 25% and new sister chromatid will have ABc gene.The probability of no recombination will be 75% and new chromosome will be ABC on single strand.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.