CBSE Class 7 Answered

Method of Seed Dispersal:

 Dispersal by Wind

Seeds dispersed by wind are usually light and small.

When mature and dry, the fruit opens and releases seeds which are dispersed by wind. Examples: Moringa (drum stick).

Dispersal by Animals

Certain birds eat fruits along with their seeds. On the ground, these seeds germinate to give rise to a new plant. Examples: Tomato, guava and chilli Some fruits cling to the bodies of passing animals or to the clothing of humans and get transported over great distances. Examples: Urena and Xanthium.

Dispersal by Water

Plants which grow along the coastal regions produce fruits which can float in water, and thereby, get transported by waves. Example: Coconut.

Dispersal by Gravitational Force

Fruits of certain plants fall on the ground due to gravitational force and the seeds are flown with the fruit. Example: Mango, Berries.

Dispersal by Internal Force

Pods of some plants burst due to evaporation of water; the seeds are blown away and dispersal takes place. Example- Black gram, Peas