Q10 of 40 Page 1

A moss plant is unable to complete its life-cycle in a dry environment. State two reasons.

Mosses live in damp and marshy areas on land. They cannot survive in dry regions.

A moss plant is unable to complete its life-cycle in a dry environment due to following reasons:


i. Mosses have rudimentary roots so it cannot absorb water from dry soil, thus, for their survival; they need to grow in moist environment.


ii. In mosses, the fertilisation of male and female gametes takes place in water.


iii. In Mosses the male gametes (flagellated sperm) swim reaches the female gamete (egg or ovum) with water as the medium and undergo fertilization.


iv. Mosses requires water for the dehiscence of antheridium the male sex organ and the opening of the archegonium-the female sex organ.


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