Question

Pteridophytic cycas characters

Answer 1

There are few pteridophytic characteristics found in Cycas.

These are as follows.

(1) Circinate vernation of young leaves.

(2) Presence of ramenta (chaff like covering over roots and shoots in some ferns).

(3) Multiciliated male gametes.

(4) Presence of Archegonia.

Hope this helps...   : )

Answer 2

Answer:

Main Characteristics of Pteridophytic Cycas:-

• Plant body is sporophytic, i.e. the plant body is divided into root, stem and leaves.
• Cycas consist of coralloid roots.
• Leaves are pinnately compound and arranged in a spiral manner at the top of the stem.
• Young Leaves consists of Circinate vernation.
• Microsporophyll form strobilus and grouped into cones. On the contrary, megasporophylls do not form strobilus and never grouped into cones.
• Ovules are very large and are formed row-wise in two sides of megasporophylls.
• Embryo consists of two cotyledons.

Explanation:

General Characteristics of Pteridophytic Cycas:-

Cycas is a slow-growing and short lived evergreen plant. Its root, stem and leaf  features are discussed below:

1) ROOT

• The primary root of Cycas is a short-lived tap root so, after primary root adventitious roots replace it.
• Most of the lateral branches of primary root which are known as normal roots penetrate the soil.

CORALLOID ROOT

Some of the roots develop near the surface and get infected with certain algae, bacteria and fungi, which are present in the soil surrounding the root system. So, become swollen at their tips.

However, they are aerotropic or negatively geotropic structures that come out in the air above the soil surface. They are branched dichotomously to form greenish-brown coral like structure, so they are called coralloid roots.

2) STEM

The stem of Cycas is erect, cylindrical and usually unbranched.

• When the stem is young, it is of tuberous, short and subterranean in nature.
• A huge number of large and small rhomboidal leaf bases cover up most of the older stem.

3) LEAF

• There are two types of leaves in Cycas such as: green, large foliage leaves, and brown, small, scale leaves.
• Foliage leaves are pinnately compound, showy, large, very thick and leathery. They are attached to the stem by rhomboidal leaves with a petiole and a long stout rachis.