Biology

Gymnosperm

Gymnosperms produce flowers and seeds but do not bear any fruit. Once they were well spread around the world but at present their, the number is becoming very limited. The total number of species of gymnosperms in the whole world is only 27. In Bangladesh, only 3 gymnosperms are found to grow naturally in the forests.

As a representative of gymnosperm the characteristics of Cycas is described here:

Characteristics of Cycas:

  1. The Cycas plant is sporophyte. Their body is divided into root, stein and leaves.
  2. They have vascular tissues.
  3. Leaves are compound, look like the leaves of coconut tree, and are arranged spirally as a crOWR on the top of the stem.
  4. Vemation of the young leaves is circinate.
  5. There are two types of root – (i) Primary root or taproot and (ii) Coralloid root, which resemble the sea corals.
  6. Female and male plants are different

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Fig: Cycas

  1. Female Sporophylls (Megasporophylls) are borne on the top of the female plant and the male Sporophylls (Microsporophylls) are on the top of the male plants. The male Sporophylls together fonn a cone like body, known as Male Cone.
  2. Seeds are developed after pollination and fertilization. New plants develop from the seed.

Importance: Cycas is planted in the garden only for beautification Cycas is found to grow wild in the forests of Chittagong.