Seed & Embryo Structures — NEET Biology

Correct answer: C — S1, S2, S4 and S5 only

Let's evaluate each statement regarding monocotyledonous embryos: S1: The single cotyledon in the grass family is called the epicotyl. This statement is NOT correct. The single cotyledon in the grass family is called the scutellum. The epicotyl is the portion of the embryonal axis above the level of attachment of scutellum. S2: The radicle and root cap are enclosed within a differentiated sheath known as the coleoptile. This statement is NOT correct. The radicle and root cap are enclosed in an *undifferentiated* sheath called the *coleorhiza*, not the coleoptile. The coleoptile encloses the shoot apex. S3: The plumule, representing the shoot apex, is covered by a hollow foliar structure called the coleoptile. This statement is correct. NCERT states, "Epicotyl has a shoot apex and a few leaf primordia enclosed in a hollow foliar structure, the coleoptile." The plumule is the shoot apex. S4: The embryonal axis portion below the level of attachment of the scutellum is the hypocotyl. This statement is NOT correct. For monocots, NCERT describes the lower end of the embryonal axis as having the radicle and root cap enclosed in the coleorhiza. The term hypocotyl is primarily used for dicots to describe the region between cotyledons and the radicle; it is not explicitly used or defined for this region in monocot embryos in the provided text. S5: Monocotyledons typically have two prominent cotyledons for nutrient storage. This statement is NOT correct. Monocotyledons possess only one cotyledon (scutellum), and in albuminous monocot seeds, the endosperm is the primary storage tissue, not the cotyledons themselves storing a prominent amount of food. Therefore, statements S1, S2, S4, and S5 are NOT correct. Option A is incorrect because S5 is also not correct. Option B is incorrect because S3 is correct. Option C is correct as S1, S2, S4, and S5 are not correct. Option D is incorrect because S3 is correct. This question tests precise knowledge of monocot embryo anatomy and the functions of its protective sheaths and cotyledon.