There is no substitute for consistent practice whether one wants to understand a concept thoroughly or one wants to score better. All India Live Test Series: Plant Kingdom (NCERT Best 90 Questions) Dec 31, 2020 • 1h 30m . NCERT Solutions for Class 11 Biology Chapter 3 – Plant Kingdom. The secondary protonema bears the sex organs which produce gametes. Economic importance of gymnosperms Soln. They are scaly and foliage also. soln.All of these plants show life cycle with one gametophytic (n) generation and one sporophytic (2n) generation. Cell wall composition — Cellulose and algin (c) Cell wall composition These algae are very useful for this purpose. (a)Chlamydomonas                                       (i)Moss (e) Gemma cell in Marchantia — Haploid Practicing such most important questions certainly help students to get good marks in exams. – The nucellus of ovule contains single megaspore mother cell which undergoes reduction division to form 4 megaspores, out of which 3 degenerate and only one survives. (i) Heterospory is associated with the sexual differentiation of gametophyte /.