Question

Questions 17 and 18 please!

17. The pathway for arginine biosynthesis in Neurospora crassa involves several enzymes that produce a series of intermediates as shown. ARG-E ARG-F ARG-G ARG-H N-acetylornithine ornithine citrulline → argininosuccinate arginine You did a cross between ARG-E- ARG-H+ and ARG-E+ARG-H Neurospora strains and identified an Arg- strain from an NPD tetrad. (Assume that Neurospora forms tetrads in the same way yeast do.) Which compound(s) from the above pathway would rescue growth of this Arg- spore: 18. How many Barr Bodies would be found in a somatic cell of an XXY individual?

Answer 1

As you demand the answer for ques 17 and 18.

But I am unable to see any question 17.

But the answer of ques 18 . I am providing below

Barr bodies is the number of inactivated X chromosomes.

Only 1 X chromosome remain activated in each and every cell irrespective of any no. Of X chromosomes .

So here 2 X chromosome is present out of which 1 remain active and 1 inactives and will be seen as barr body in the somatic cell of an individual with a XXY ( klinefelter's syndrome) .

Barr bodies = { No. Of X chromosomes in a cell - 1}