Monosporic Female Gametophyte Development — NEET Biology

Correct answer: C — S1 and S4 are correct

Let's evaluate each statement: S1: The tapetum is indeed the innermost wall layer, and its cells possess dense cytoplasm and generally have more than one nucleus to nourish the developing pollen grains. This statement is correct. S2: The exine is the hard outer layer made up of sporopollenin, while the intine is the inner, thin, and continuous layer made up of cellulose and pectin. This statement incorrectly describes the exine's composition and location. This statement is incorrect. S3: Microsporogenesis is the process of formation of microspores from a pollen mother cell (PMC) through meiotic divisions, not mitotic divisions. This statement is incorrect. S4: In a majority of flowering plants, one functional megaspore develops into the female gametophyte (monosporic development). The nucleus of this functional megaspore undergoes three successive free nuclear mitotic divisions to form the 8-nucleate stage. This statement is correct. S5: The egg apparatus, consisting of two synergids and one egg cell, is grouped together at the micropylar end of the embryo sac, not the chalazal end. This statement is incorrect. S6: The filiform apparatus is present at the micropylar tip of the synergids, not in the antipodal cells, and it guides the pollen tubes into the synergid. This statement is incorrect. Therefore, only statements S1 and S4 are correct. The core concept tested here involves the structural and developmental details of microsporogenesis, pollen grains, megasporogenesis, and embryo sac formation, highlighting key cellular characteristics and processes.