Answer: phyllotaxy.
- A phyllotaxy
- B aestivation
- C venation
- D placentation
Correct answer: A. phyllotaxy
Explanation: Phyllotaxy is the pattern of arrangement of leaves on the stem.
In a dicot stem, vascular bundles are arranged in a single ring (with cambium between xylem and phloem, enabling secondary growth); in a monocot stem, bundles are scattered throughout with no cambium, so monocots can't undergo secondary growth (no wood formation).
Concept context
External structure of roots, stems, and leaves plus internal tissue organization. High marks in Class 11 and NEET.