The commerical cork is obtained from the cork tissue of Quercus suber, which yields bottle cork. Cork is formed by cork cambium or phellogen cell. Cork cambium cells divide periclinally, cutting cells towards the inside and outside. The cells cut off twowards the outside become suberised and dead. These are compactly packed in radial rows without intercellullar spaces and form cork of phellem. Cork is impervious to water due to suberin and provides protection to the underlying tissues.

(a) Coir It is a natural fibre obtained from husk of coconut. It is the fibrous mesoderm of the coconut fruit Cocos nucifera.

(b) Hemp The fibre is obtained from the stems of Cannabis sativa. It is the bast fibre (soft or stem fibre) obtained from secondary phloem.

(c) Cotton The fibre is the epidermal growth of cotton (Gossypium hirsutum) seed. It is elongated structure made up of cellulose.

(d) Jute It is a natural bast fibre obtained from Corchorus capsularis and made up of cellulose and lignin.

Difference between gymnosperm and angiosperm is as follows

Gymnosperm	Angiosperm
Gymnosperms lacks vessels in their xylem. Phloem lacks companion cells.	Vessels present in the xylem. Phloem possesses companion cells.

Modification of Epidermal Cells

The epidermal tissue has the following modifications

(i) Root hair

Structure	Function
Unicellular hairs are the extensions of epidermal cell of roots in the root hair zone.	It increases the surface area for absorption of water and minerals.

(ii) Epidermal Appendages

Structure	Function
These are called trichomes and are epidermal cell modifications. There may be unicellular or multicellular.	Some performs for stinging produces and some glandular secretions.

The meristematic tissue is responsible for the rapid growth of such mowed lawn grass. When the apex of grass is cut frequently, it leads to the growth of the lateral branches, that makes it more bushy.