Q.6

What is the ploidy level of a sporophyte in angiosperms?

(A) n

(B) 2n

(C) 3n

(D) 4n

Ploidy Level of Sporophyte in Angiosperms: Correct Answer and Explanation

The sporophyte in angiosperms maintains a diploid (2n) ploidy level, representing the dominant phase of their life cycle. This diploid nature arises from zygote formation via fertilization, distinguishing it from the haploid gametophyte.

Correct Answer

The correct option is (B) 2n. In angiosperms, the sporophyte develops from the diploid zygote formed by the fusion of haploid egg and sperm nuclei. This diploid phase undergoes meiosis in sporangia to produce haploid spores, perpetuating the alternation of generations.

Option Explanations

• (A) n: Incorrect, as this haploid level applies to the gametophyte or gametes, not the sporophyte, which forms post-fertilization.

• (B) 2n: Correct, matching the diploid sporophyte across angiosperms, including the familiar plant body like stems and leaves.

• (C) 3n: Incorrect; triploidy occurs in endosperm due to double fertilization (two maternal + one paternal nucleus), not the main sporophyte.

• (D) 4n: Incorrect, as tetraploidy is rare and not standard for angiosperm sporophytes, which remain diploid unless polyploidy mutations intervene.