Question

Can anyone explain qsn 50 and 55

50) How many meiotic divisions will be necessary to produce two hundred pollen grain-
a)100
b) 99
c) 50
d) 200
55) What will be the gametic chromosome number of
a cell, if somatic cell have 40 chromosome-
a) 10
b) 20
c)30
d) 40 ​

Answer 1

Dear student,
(A) In the pollen sacs, 4 pollen grains are produced after 1 meiotic division. Therefore, in order to produce 200 pollen-grains 50 meiotic divisions will be required.
(B) Meiosis results in the production of four daughter cells each containing half the needed chromosome i.e meiosis create 4 haploid cells. In other words, gametic chromosomes contain half the number of chromosome than the somatic cells. Therefore, if a somatic cell has 40 chromosomes then the number of chromosomes in the genetic cell will be 20.

Regards.