NEET Previous Year Question
Select one of the following pairs of important features distinguishing Gnetum from Cycas and Pinus and showing affinities with angiosperms :-
Topic: NEET PYQ
Answer: D. Full step-by-step solution below.
- APerianth and two integuments
- BEmbryo development and apical meristem
- CAbsence of resin duct and leaf venation
- DPresence of vessel elements and absence of archegonia
Correct answer: D
Solution
(d) Presence of vessel elements: Most gymnosperms, including Cycas and Pinus, lack vessel elements in their xylem, relying solely on tracheids for water conduction. Gnetum is unique among gymnosperms for possessing vessel elements, a characteristic typical of angiosperms.Absence of archegonia: In most gymnosperms (like Cycas and Pinus), female gametes are produced within specialized structures called archegonia. In Gnetum, archegonia are absent, and some free nuclei within the female gametophyte function directly as eggs, similar to the simplified gametophyte structure of angiosperms.More The Living World PYQs
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