General
UNIT 11: Plants
Plants are living things. They grow from seeds.
Most plants bear seeds. Seeds germinate and grow into new plants.
1. Take some gram seeds.
2. Sow them in your school garden.
3. Sprinkle water to keep the soil moist.
4. Observe them daily for 3–4 days.
When seeds get enough air, water and light, they grow into new plants or seedlings.
The growing of seeds into seedlings is called
Every seed needs certain favourable conditions to germinate.
Four containers, cotton wool, some viable and non-viable cowpea seeds and a cupboard.
1. Take four containers marked A, B, C and D as follows:
A with dry cotton wool. B, C and D with moist cotton wool.
2. Place 3–4 viable (healthy) cowpea seeds at the top of the cotton wool in containers
A, B and D and non-viable (unhealthy) seeds in container C.
3. Place containers A, B and C in sufficient light and air.
4. Place container D in the cupboard.
5. Observe them daily for 3–4 days.
6. Discuss your findings in the class.
After 3–4 days, you may observe that seeds in containers A, C and D remain unchanged.
The seeds in container B have germinated. Find out why.
Like other organisms, plants also have different parts.
Each part has a specific function to perform. Let us know about them.
1. Visit your school surroundings.
2. Uproot a small flowering plant and observe its various parts.
3. Name these parts
4. Also discuss their functions in the class.
It is the underground part of the plant. It has the following functions:
1. Roots fix the plant into the soil.
2. They absorb water and minerals from the soil. Water and minerals are important for plants to grow healthy.
3. In some plants, roots store extra food. For example, carrot, radish and beetroot .
It is the aerial part of a plant. It has the following functions:
1. The stem supports branches which bear leaves, buds, flowers and fruits.
2. It transports water and minerals from the roots to the leaves and fruits.
3. In some plants, stems store extra food. We eat these stems.
For example, Irish potato, ginger and sugarcane.
It is the most important part of a plant. Most plants have green leaves.
Some functions of a green leaf are:
1. A green leaf makes food for the plant.
2. Air and water vapour go in and out of the leaf.
Thus it helps the plant to breathe.
3. In some plants, leaves store extra food.
We eat these leaves.
For example, spinach, cabbage and coriander.
Flowers are colourful and pretty. They are the reproductive parts of a plant.
Some functions of the flower are:
1. Flowers turn into fruits.
2. They give off a sweet smell.
So they are used to decorate houses and gardens.
3. Flowers like pyrethrum are natural insecticides.
4. We eat some flowers, for example, cauliflower and broccoli.
When seeds get enough air, water and light, they grow into new plants or seedlings.
The growing of seeds into seedlings is called germination.
During germination, cotyledons of some seeds come out of the ground.
Such type of germination is called epigeal germination.
During germination, cotyledons of some seeds remain under the surface of the soil.
Such type of germination is called hypogeal germination.
There are different types of plant such as trees, herbs and shrubs.
Branch, fruit, flower, leaf, stem and root are the main parts of a plant.
The stem is the main part of the shoot.
Branches, leaves, buds, flowers and fruits grow on it.
A green leaf makes food for the plant.
Flowers are the reproductive parts of a plant.
Do these review exercises in your exercise book.
1. When a seed gets enough air, water and sunlight, it grows into a seedling.
This process is known as ..................... .
(a) germination (b) pollination
(c) dispersion (d) none of these
2. The tall plants are called ……………… .
(a) shrubs (b) herbs
(c) trees (d) none of these
3. ………….. live for one season or for a few months.
(a) Shrubs (b) Trees
(c) Herbs (d) All of these
4. Fruits are produced from ……………… .
(a) roots (b) stems (c) leaves (d) flowers
5. …………. transports water and minerals from the roots to the leaves and
fruits.
(a) Root (b) Leaf
(c) Stem (d) Flower
1. Seeds germinate and grow into new plants.
2. Epigeal germination occur in maize seeds.
3. Hypogeal germination occurs in bean seeds.
4. Roots absorb water and minerals from the soil.
5. Flowers are the reproductive parts of a plant.
1. Define germination.
2. List two types of germination.
3. Define trunk of a tree.
4. Write the names of two shrubs.
5. Write any two functions of roots.
6. We eat some flowers.
Can you name any two flowers that we eat?
7. Write any two functions of flower and fruit.
Across
2. The part of the shoot which bears branches, leaves, flowers and fruits.
3. A tall plant with a trunk and branches made of wood.
4. A flowering plant whose stem is not woody
Down
1. A small to medium-sized woody plant.
2. A small hard part of a plant from which a new plan grows.