1. Gymnosperms (gymnos – naked, sperma = seed) are naked – seeded plants. Here the ovules are not enclosed and thus the seeds remain naked.

2. Most of the gymnosperms are evergreen, woody perennials with shruby or tree like habit. They show xerophytic characters.

3. The main plant body is a well differentiated sporophyte consisting of root, stem and leaves. Gametophyte is reduced and is dependent on sporophyte.

4. Plants possess well developed root system.

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5. Leaves are of two types i.e. foliage leaves and scale leaves.

6. Vascular bundles are conjoint, collateral, open and endarch.

7. Xylem consists of only tracheids.

8. Vessels are absent except in Gnetum.

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9. Companion cells are absent.

10. Secondary growth takes place both in roots and stems.

11. Reproductive parts are generally in the form of compact and hard cones or strobili. The cones are generally unisexual.

12. In male cones, many microsporphylls are arranged on a central axis. Microsporophyll’s bear micro sporangia containing microspores or pollen grains.

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13. Archegonia lack neck canal cells.

14. Pollination is of anemophilous type.

15. The ovules are covered by single integument and are orthotropous type. The ovule is a modified mega sporangium borne directly on the surface of megasporophyll.

16. Endosperm is formed before fertilization.

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17. Polyembryony is exhibited by many members of gymnosperms.

18. Embryo is formed inside the ovule. The ovule gets transformed into seed.

19. Epigeal mode of germination is seen.

20. Plants show distinct alternation of generation.

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Cycas (Sago palm)

Systematic position

Kingdom – plantae

Division – Gymnospcrmac

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Sub – class – Cycadophyta

Order – Cycadales

Family – Cyeadaeeae

Genus – Cycas

(About 20 species)

Cycas is a small evergreen plant with an average height of 1.5-3.0 meters. It resembles a “palm-fern” or “tree-fern”. Hence it is also called “palm-fern” or “Tree- fern”. Its species are distributed in Australia, Madagascar, East Africa, South China, Japan and India.

In India, it occurs naturally in Orissa, Bengal, Assam and Southern States. Cycas is represented by five species in India e.g. Cycas revoluta, C. circinalis, C. rumphii, C. pectinata, C. beddomei. C. revoluta is grown in Indian gardens. C.circinalis is planted in pots. Sago is obtained from the stem of C.revoluta. Thus it is called as Sago-palm.