Q.62 Which two of the following are the INCORRECT statements ?
P. In monocotyledonous stems with closed vascular bundle, secondary growth takes place without
any cambium
Q. In dicotyledonous stems hypodermis is collenchymatous
R. Mobilization of storage reserves takes place during post-germination of embryo
S. Osborne’s classification of seed storage proteins is based upon solubility in n-hexane
(A) P,R (B) Q,S (C) Q,R (D) P,S
Statements Q and S are incorrect, making option (B) correct.
P and R are true, while Q misstates dicot stem hypodermis and S wrongly attributes Osborne’s classification to n-hexane.
Statement Analysis
P (True): Monocot stems have closed vascular bundles lacking interfascicular cambium, so typical secondary growth via vascular cambium doesn’t occur—though anomalous growth exists in some (e.g., Dracaena).
Q (False): Dicot stems have collenchymatous hypodermis (correct fact), but statement claims it—wait, no: standard botany confirms dicot hypodermis IS collenchymatous, monocot sclerenchymatous. If Q says “is collenchymatous,” it’s TRUE. Re-evaluate per sources: Actually, upon check, Q is TRUE for dicots. Wait—question seeks INCORRECT; need precise error.
Corrected Breakdown:
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P (Incorrect): False claim—monocots generally lack secondary growth BECAUSE no cambium; statement wrongly implies growth “takes place without cambium.”
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Q (Correct): Dicot hypodermis is indeed collenchymatous.
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R (Correct): Seed reserves mobilize post-germination for embryo growth.
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S (Incorrect): Osborne classifies proteins by solubility in water (albumin), saline (globulin), alcohol (prolamin), alkali (glutelin)—not n-hexane (for lipids).
Thus, incorrect are P and S → (D).
Option Breakdown
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(A) P,R: Wrong—R true.
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(B) Q,S: Wrong—Q true.
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(C) Q,R: Wrong—both true.
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(D) P,S: Correct—both false.
Introduction to Monocotyledonous Stems Secondary Growth
Monocotyledonous stems secondary growth seed storage proteins questions test plant anatomy in GATE Life Sciences. Identify incorrect statements: monocots lack cambium-driven growth (P wrong), Osborne uses solvents not n-hexane (S wrong).
Statement Verification
| Statement | Status | Explanation |
|---|---|---|
| P | Incorrect | No secondary growth in closed bundles sans cambium. |
| Q | Correct | Dicot hypodermis collenchymatous. |
| R | Correct | Reserves mobilize post-germination. |
| S | Incorrect | Osborne: water/salt/alcohol/alkali, not hexane. |
GATE Strategy
Focus monocotyledonous stems closed vascular bundle exceptions, protein solubility for PYQs. Option (D) P,S scores.
