Question

The ploidy of zygote, endosperm, egg cell, nucellus respectively are

• A. 3n, n, 2n, 2n
• B. 2n, 3n, n, 2n
• C. n, 2n, 3n, 2n
• D. 3n, 2n, 2n, n

Hint:

In angiosperms: zygote = 2n, endosperm = 3n, gametes = n, sporophytic tissues = 2n.

Answer 1

The Correct Option is B

Step 1: Understanding ploidy terms.
Ploidy refers to the number of sets of chromosomes present in a cell. In flowering plants, different structures show different ploidy levels.

Step 2: Zygote ploidy.
The zygote is formed after fertilization and is diploid (2n).

Step 3: Endosperm ploidy.
Endosperm is formed by triple fusion and is typically triploid (3n).

Step 4: Egg cell ploidy.
The egg cell is a gamete and therefore haploid (n).

Step 5: Nucellus ploidy.
Nucellus is a part of the ovule and is diploid (2n).

Step 6: Final conclusion.
Thus, the correct sequence is 2n, 3n, n, 2n.
\[ \boxed{(2)} \]