Getting to know plants (Part-6)

       Getting to know plants 

Q.17. What are the functions of root?

Ans. The functions of root are:

•   The roots help in holding the plant firmly in the soil. They are said to anchor the plant to the soil.

•    Absorption of water and minerals from the soil.

•    Help to bind soil particles together.

•   Sometimes roots are modified to perform additional functions like reproduction, nutrition etc.

 Q.18. What are tap roots? Draw a sketch of tap roots.

Ans. Characteristics of tap roots:

•     In the tap root system, a single straight tapering root (called the primary root) grows vertically down into the soil and give out branches on all sides. Tap roots are also called true roots.

•      Later smaller roots called lateral roots branch out from this primary root.

•      Mango, neem, pine, sheesham, pea, carrot, radish, turnip, and beetroot plants have taproot.

      

Q.19. What are fibrous roots? Draw a sketch of fibrous roots.

Ans. Characteristics of fibrous roots:

·      The fibrous roots consist of many thin, fibre-like roots of a similar size.

·    These roots are thin and almost equal in size. They spread out in the soil and give a firm support to the plant.

·      Grass, maize, wheat, onion, sugarcane and rice have fibrous roots.

Q.20. If a plant has fibrous root, what type of venation are its leaves likely to have?

Ans. Parallel venation

Q.21. If a plant has leaves with reticulate venation, what kind of roots will it have?

Ans. Tap root

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