Page 58 - Viva ICSE Science 5 : E-book

• The seed needs favourable conditions like right soil, water, sunlight and air to grow
into a plant.

• In favourable conditions, the seed coat becomes soft and spongy.

• At this stage, the seedling breaks the seed coat and comes out of the seed. It obtains
its food firstly from the cotyledons and then from the soil.

• The seedling develops roots and shoot. Roots grow underground and help in
absorbing water and nutrients from the soil.

• The shoot grows above the ground. It develops leaves and branches, and fi nally
grows into a plant.

1 2 3 4

Stages of germination in a seed

TIME TO REVISE

Defi ne the following.
1. Reproduction 2. Embryo 3. Fertilisation 4. Germination

Need of Dispersal for Survival

Not all seeds grow into plants. Some seeds are damaged by animals, insects, wind or
water. Some may not receive appropriate conditions of growth like soil, air, water or
warmth. When too many seeds fall near the parent plant, they compete with each other

for suitable conditions. As a result, only a few of them survive while the rest die. To avoid
growing very close to each other, seeds need to disperse. Agents like wind, water and

animals help to scatter seeds. This process by which the seeds are scattered away from
the parent plants is called dispersal.

Agents of dispersal
The process of dispersal is carried out by agents like wind, water, animals and explosion.

To facilitate dispersal by diff erent agents, many seeds and fruits have developed special

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