Question

If the egg of an organism has $40$ pg of DNA in its nucleus, how much DNA would a diploid cell of same organism have in pachytene(X), diakinesis(Y) and anaphase-I(Z)?

• A. X$=160$ pg, Y$=160$ pg, Z$=160$pg
• B. X$=80$ pg, Y$=80$ pg, Z$=160$pg
• C. X$=160$pg, Y$=80$ pg, Z$=160$pg
• D. X$=80$pg, Y$=160$pg, Z$=80$ pg

Answer 1

Answer: (B)

X$=80$ pg, Y$=80$ pg, Z$=160$pg

$\Rightarrow$ In diploid cell $2n=2\times 40pg=80pg$.

In meiosis $1$ replication in its s phase but the same doesn't apply for meiosis $2$ because replication doesn't occur in its interphase.

And now $G_2$ comes after s phase so in $G_2$ after replciation DNA content become double and its becomes $160$pg.

So,

$x=80pg$,

$y=80pg$,

$z=160pg$.