A couple is accidentally exposed to a high dose of x-rays by a malfunctioning plasma TV preventing random assortment and crossing over from occurring when they form gametes.

A) How would this affect their sex cells?

B) What would be the result when the couple had children?

Question

A couple is accidentally exposed to a high dose of x-rays by a malfunctioning plasma TV preventing random assortment and crossing over from occurring when they form gametes. 

A) How would this affect their sex cells? 

B) What would be the result when the couple had children?

sweetburger · Answer

Well if random assortment couldn't occur i guess you either assume that the chromosomes dont line up at the metaphase plate or that they will always allign the same way at the metaphase plate. This will reduce genetic variation in the offspring. If crossing over cannot occur segments of sister chromatids from non-homologous chromosomes will not break off and will not rejoin with other chromosomes. This is also going to reduce genetic variation.

nnumesi · Answer

Meiosis results in  two events of crossing over and two divisions.  Thus out of two sets of genes (Mom and Dad)  the end result is 4 daughters with maximum variation of  genetic attributes (combinations from mom and dad).

If Crossing over doesn't occur, you would in effect have a chance of some daughter cells with too much DNA genetic information and some daughter cells with too little to survive as progeny.