Germination of seeds for kids - What is germination?

Germination of seeds for kids - What is germination?

Have you ever tried to grow your own plants?
If you have, you may have started with seeds.
Plants have male and female parts.
In seed-bearing plants, the male reproductive cells, called sperm, are carried in tiny grains called pollen.
These cells are released into the ovary, the female part of the plant.
There, one of the sperm joins with a female reproductive cell, called an egg, to start a new plant.
This tiny new plant, called an embryo, is at first kept in a seed with its own store of food.
Seeds can be many different shapes and sizes but they all do the same job. They are scattered away from the parent plant.
The outer cover of each seed protects the embryo until the seed lands in a suitable place. When conditions are right, the seed takes up water and the new plant grows out of it.

This is called germination.

What do seeds need to germinate?

How do seeds germinate?

The name for the moment in which seeds start to grow is germination. Seeds come in many different shapes and sizes—big ones, small ones, round ones, flat ones, and thin ones.
No matter what they look like, each seed has a tough outer coat and enough stored food to start growing.
Some seeds can wait a long time before they germinate.
If you buy a packet of seeds and keep it dry, you can plant the seeds several years later and they will still grow into healthy plants. Some seeds of poppies and docks have stayed underground for many years before germinating into new plants!
When a seed germinates, one part grows upwards and one part grows downwards.
The part that grows upwards is called a shoot, and the part that grows downwards is called a root.
Seeds will not germinate until they receive three things— water, warmth and oxygen—all at the same time and in the correct amounts.

Roots And Shoots

Did you know that shoots grow upwards? Shoots grow toward the light, which they need in order to make their own food. Sunlight provides the energy that plants use to make the sugars and starches that are their food.
 
Did you know that roots grow downwards?
Roots fix plants firmly in the ground. Large trees, for example, have many big spreading roots to anchor them. Roots also absorb water and other nutrients to help plants grow.

Plants without Seeds, Spores


Some plants can reproduce themselves without using seeds or spores. Many of these plants have male and female parts, but they may not use them to make seeds or spores. Instead, new plants develop from special buds on the parent plant.
Tiny organisms called algae may be so small that each is made up of just one plant cell. This cell can split into two to make two separate algae. This splitting process is called binary fission.
Beach grass grows new plants from a network of long stems that spread sideways underground. This is very useful in sand dunes near the sea, because the stems anchor the plant in the ground and at the same time stop the wind from blowing all the sand away.
The part of the potato plant that we eat is called the tuber. Tubers are part of the stem that grows underground. If they are not dug up and eaten, the tubers will grow into new potato plants. Look closely at a potato and you'll see the small buds, called eyes, that grow into new plants.
Bryophyllum is called the good luck plant. Tiny new plants grow on the edges of its leaves. The new plants drop down to the ground, root themselves and start growing as separate plants.
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