NCERT Class VII Science Solutions: Chapter 12-Reproduction in Plants Part 4

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Question 8:

Describe the various ways by which seeds are dispersed.

Answer:

Following are the various methods of seed dispersal:

This image shows how seeds travel

How Seeds Travel

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Dispersal by Wind:

  • Seeds of some plants are light-weight and some hair-like or wing-like structures are present on them. Such seeds float on air and are thus dispersed by wind. Example: Dandelion, maple, drumstick, etc.

As showing in images is a Dispersal by Wind

Dispersal by Wind

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Dispersal by Water:

  • Dispersal by water takes place in some aquatic plants and in some which grow near a water body. Seeds of water lily float and thus dispersed by water. The coconut seed has a tough fibrous covering which has plenty of air inside. This helps the coconut seeds in floating on water.

As showing in images is a result for Dispersal by Water

Result for Dispersal by Water

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Dispersal by Animals:

  • Some seeds have spine like structures on them. They get stuck to the fur of animals and thus get spread to different places. Examples; Beggar tick, Xanthium, etc. Some seeds are swallowed by birds and animals along with fruits. These seeds get dispersed with bird or animal droppings.

As showing in images is a result for Dispersal by Animals

Result for Dispersal by Animals

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Dispersal by Bursting:

  • Some fruits burst open when they mature. The force of bursting is enough to spread the seeds. Examples; Ladyfinger, castor, balsam, etc.

As showing in images is a result for Dispersal by Bursting

Result for Dispersal by Bursting

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Dispersal by Humans:

  • Human beings also help in dispersal of seeds, especially during farming.

As showing in images is a Dispersal by Humans

Dispersal by Humans

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