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Following are a few organisms Which amo...

Following are a few organisms Which among the above can grow on stones, and also help in formation of soild? Write the mode of their action from making soil.

A

lichen

B

mosses

C

mago tree

D

cactus

Text Solution

Verified by Experts

The correct Answer is:
A

Out of the above given organisms lichens can grown on rocks. During growth, they release certain substances that cause the rock surface to powder down and form a thin layer of soil. Lichens grow on the rock surface, extract minerals from them. This creates small crevices at places where a thin layer of soil builds up. Mosses grow over these crevices and cause deepening of the crevices and result in wider and deeper when the roots of short lived herbs pass into them. With the passage of time, the roots of bigger plants, (e.g., peepal banyan tree) pass into the cracks. Cracks gradually widen and cause slow fragmentation and eventually pulverisation of rocks.
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NCERT EXEMPLAR ENGLISH-NATURAL RESOURCES -Short Answer Type Questions
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  2. How can we prevent the loss of top soil?

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  3. How is the life of organisms living in water affected when water gets ...

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  4. During summer, if you go near the lake, you feel relief from the heat,...

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  5. In coastal area, wind current moves from the sea towards the land duri...

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  6. Following are a few organisms Which among the above can grow on stone...

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  7. Soil formation is done by both abiotic factors. List the names of thes...

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  8. All the living organisms are basically made up of C,N,S,P,H and O, . H...

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  9. Why does the percentage of gases like oxygen, nitrogen and carbon diox...

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  10. Why does moon have very cold and very hot temperature variations e.g.,...

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  11. Why do people love to fly kites near the seashore ?

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  12. Why does Mathura refinery pose problems to the Taj Mahal?

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  13. Why do not lichens occur in Delhi whereas they commonly grown in Manal...

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  14. Why does water need conservation even though large oceans surround the...

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  15. There is mass mortality of fishes in a pond. What may be the reasons?

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  16. Lichens are called pioneer colonisers of bare rock. How can they help ...

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  17. Soil is formed by water'. If you agree to this statements then give re...

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  18. Fertile soil has lots of humus. Why?

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  19. Why step farming is common in hills?

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