Saturday, March 5, 2016



Children in these lesson we are going to learn about seed germination and dispersal of seeds.

Gopal was waiting for his mausi’s family to visit them. They will be coming the next day for their holidays. He was thinking about all the fun and nice food that he would have with his cousins.

Just then his mother called out, “Gopal, before you sleep, remember to soak two small bowls (katoris) of chana (gram).” She was going to his Bua’s house and would return only in the morning.

As he was soaking the chana, Gopal thought, “How will two small bowls of this be enough for eight persons?” So he soaked another two bowls of chana.

When his mother returned the next morning, she saw that the chana were overflowing from the vessel. “How much did you soak?” asked his mother. “How did that happen!” wondered Gopal.

“You soaked too much! Anyway it is good, now I will cook half of them, and leave the other half to sprout. I can send these to your aunt. The doctor has told her to eat sprouts”, mother said. She tied half of the soaked chana in a wet cloth, and hung them up to sprout.

Let us see about seed germination:
Growing plants from seeds:
Children if u eat an apple or an orange you will fine deeds inside. New plants can grow from these seeds.

Not all seeds grow into new plants . some seeds are eaten up by birds and insects. Some seeds get destroyed by the rain or wind. If seeds get sufficient amount of air, water, warmth it grows in to new plant .

 A seed producing a new bady plant  or seedling . this process we called as seed germination.

During the early stages of germination , the sedling gets the foods which ift requires for its growth from the cotyledous. The food which stored in cotyledous has been used up the seedling gets its food from the soil.

The seddlings absorbs water and nutrients from the soil with the help of its roots. The it develops new leaves and grows in to a new abay plant.

Now it requires air for seed germination. The air reaches the seed through pores in the soil. That is why soil is so important for plants growth.

Afte they germinate, they will struggle for air, water, light, nutrients and the space to grow. As a result, many of them would die.

Structure of seed:
Children have you seen a bean or a gram seed. It is hard and cannot be broken easily. The hard outer covering layer is alled the seed coat. The seed coat protects the sed.

 The seed has two cotyledons. These are special seed leaves which protect baby plant or embryo. They also store food for the embryo.
Seeds like grmas, beans and peas have two cotyledons while seeds like wheat and corn have only one cotyledon.

Let us see about seed dispersal:
Seed Dispersal: The process by which seeds are scattered away from the mother  plant is called dispersal.

Seed Dispersal By Water: some plants of seeds like lotus and coconut are spongy in nature or they have a fibrous covering, on they outer surface. This help them to float on water easily. Water carries these seeds easily from one place to another. this type if dispersal is called as Seed Dispersal by water.
Example: lotus, coconut and water lilly.

Seed Dispersal By Wind: some seeds of certain plants are very light in weight and have wing-like structures or hair on them. These type of seeds can easily carried away by the wind from one place to another place. This type if dispersal is called as Seed Dispersal by wind.
Examples: Plants like cotton, dandelion and madar.

Seed Dispersal By Explosion: the fruits of some plants just like poppy, pea and bean. These fruits can burst and open when they ripe, scattering the seeds in all directions . this type if dispersal is called as Seed Dispersal by explosion.
Examples: fruits like pea and balsam.

Seed Dispersal By Animals: some plants cocklebur seeds have spine or hooks on their body. These seeds stick to the bodies of animals and birds. So they carried away from the mother plant. this type if dispersal is called as Seed Dispersal by animals.
Examples: plants like xanthium,tigernailsma and spear grass.

These are the various types of dispersal of seeds which grows in to a new baby plant.

This happened in 1948. One day George Mestral came back from a walk with his dog. He was amazed to find seeds sticking all over his clothes and on his dog’s fur. He wondered what made them stick. So he observed these seeds under a microscope. He saw that the seeds had many tiny hooks which got stuck to clothes or fur. This gave Mestral the idea of making Velcro. He made a material with similar tiny hooks that
would stick. Velcro is used to stick together many things – clothes, shoes, bags, belts and many more. What a way to take inspiration from nature!

Who came from where:
Have you included human beings also in your list? Yes, we also carry seeds from one place to another, knowingly or unknowingly. We bring the seeds of plants that we find beautiful or useful, to grow them in our garden.

Later the seeds of these plants spread to other places. Many years later people may not even remember that these plants did not grow here earlier. They were brought from somewhere else. Here some of the seeds they dispersal from one place to another

Do you know from where chillies came to our country? These were brought to India by traders coming from South America. Today we cannot think of food without chillies!

From South America long ago, came a tomato, a potato, and a green chilli. Do you know this?

A cabbage came from Europe, and also a pea. From Africa came a coffee bean, and a green bhindi.

A mango sang, ‘Come in! Come in!’ An orange smiled inside its skin. ‘Welcome to India,’ a banana said. the methi and spinach, brinjal and radish, nodded its head.

Pants from sopres:
Some plants like fren, fungi and moss do not have flowers. So, they do not not produce seeds. They produce tiny spores. This spores develops into new baby plant.

Plants grow different body parts;
Some plants grow from the body parts of the parent plant. The method of obtaining new plants from the leaves, stem and roots of the parent plant is called vegetative propagation.

Plants like potato and ginger have eyes on them. Under suitable conditions they grow in to a bud from new baby plant growa.

Onion and ginge plants also grow from their underground bulb –shaped stems.

Plants like bryophyllum, gorws from the edges of leaves buds.
Some plants grows from buds on the stem examples rose hibiscus, sugarcane etc.



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