Optimum Temperature & Environmental Growth Signals — NEET Biology

Correct answer: C — S1, S2, S3, and S5 only

Let's evaluate each statement based on the NCERT text: S1: "Turgidity of cells helps in extension growth. Thus, plant growth and further development is intimately linked to the water status of the plant. Water also provides the medium for enzymatic activities needed for growth." This statement is correct. S2: "Oxygen helps in releasing metabolic energy essential for growth activities." This statement is correct. S3: "Nutrients (macro and micro essential elements) are required by plants for the synthesis of protoplasm and act as source of energy." This statement is correct. S4: "Environmental signals such as light and gravity also affect certain phases/stages of growth." They influence growth directions and patterns (e.g., tropisms), but are not primarily direct metabolic inhibitors. This statement is incorrect. S5: "every plant organism has an optimum temperature range best suited for its growth. Any deviation from this range could be detrimental to its survival." This statement is correct. S6: "Many of the extrinsic factors such as temperature and light, control plant growth and development via PGR." This indicates PGRs do not operate independently of environmental signals. This statement is incorrect. Therefore, statements S1, S2, S3, and S5 are correct. Final Answer: The final answer is C because S1, S2, S3, and S5 are correct.