Q.Mention two characters shared by gymnosperms and angiosperms.

Gymnosperms have naked ovules/seeds and single fertilization with no true fruit, while angiosperms have enclosed ovules that mature into fruits, true flowers, and double fertilization producing a nutritive triploid endosperm.

Major differences between Gymnosperms and Angiosperms:

1. Ovules/seeds: in gymnosperms the ovules (and later the seeds) are NAKED, borne exposed on the surface of open megasporophylls (cone scales), not enclosed in any ovary; in angiosperms, the ovules are enclosed within a closed ovary.

2. Flowers and fruits: gymnosperms lack true flowers (their reproductive structures are cones/strobili) and never form a true fruit; angiosperms produce true flowers, and after fertilization the ovary develops into a true fruit that encloses the seed(s).

3. Fertilization: gymnosperms show SINGLE fertilization (only the egg is fertilized by a male gamete); angiosperms show DOUBLE fertilization (syngamy of egg + male gamete, plus triple fusion of polar nuclei + the second male gamete).

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