CBSE Class 5 Science – 1. Growing Plants (Notes)

Germination: -The process by which plants reproduce their own kinds is called germination.

The three things are required for germination –Air , Water, Warmth (heat)

 

Reproduction: -The process by which animals reproduce their own kinds is called reproduction

Most plants reproduce through seeds. 

Some plants reproduce through spores.

Some plants reproduce through their body part.

 

Reproduce through seeds:-Seed plants have special structures on them where male and female cells join together through a process called fertilisation.

When seeds come in favourable condition (air, water & warmth) it fertilises.

After fertilisation, a tiny plant called an embryo is formed inside a seed.

The seed protects the embryo and stores food for it.

If the seed lands where the conditions are right, the embryo germinates and grows into a new plant.

When the plant will develop a root system it will absorb water and nutrients from the soil.

The shoot system of the plant will develop and now the leaves will start preparing food for the plant then the cotyledons will shrink and disappear.

 

Seed plants divided into two main groups: –

Plants that have flowers are called angiosperms (Flowering Plants).

Plants that hold their seeds in cones are called gymnosperms (Non-Flowering Plants).

 

Part of seed

Epicotyl (will become the shoot-stems and leaves) Radicle (embryonic root) Hypocotyl (connection between cotyledon and radicle) Cotyledon (seed leaf) Note: The seed has one cotyledon is called monocot. Ex- Corn (wheat, rice, maize, malate etc.)      The seed has two cotyledons is called dicot.     Ex- Bean, gram, Arhar, pea etc.

Seed dispersal:-The process by which seed are scattered away from the mother plant is called Dispersal.

 

1. By wind – The seeds that are light in weight have wing like structure or hair like structure can be easily carried away by the wind from one place to another. For e.g. – cotton seed.
2. By water – Seeds that have a fibrous covering that can bloat on water can be dispersed by this method. For e.g. coconut and lotus.
3. By animals – seeds that have hooks or spines can stick on the body of the animals and so can be carried away from one place to another by the animals. For e.g. – cocklebur.
4. By explosion – Fruits of some of the plants burst open when they are ripe and scatter the seed in all directions. For e.g. – poppy, pea and beans.
5. By humans –  Human beings also help in dispersal of seed mainly while they are farming. Ex- Wheat, Paddy, Pea and Coriander etc.

 

 

Reproduce through spores:- 

Those plants which have no flower and seeds they reproduce by their tiny spores.

Ex- Ferns, Liches and mosses.

 

Reproduction by parts of plant:-   

Some plants grow new plants from their body parts by a certain method.

They are- Budding, Fragmentation, Spore Formation, And Vegetative Propagation.

 

The different parts of the plants from which a new plant can grow are the following –

From Buds –      

Some plants have underground stem they have bud also when they put in soil, the new plants grow from buds.  

Stem of these plants are thick and fleshy they store food in their stem.

Ex –  Potato and Ginger

Vegetative reproduction: – The process in which new plants are grown from the parts of the plant other than seed is called vegetative reproduction.

From roots – Some plants store food in their roots, so the new plants can grow from the roots of these plants.       Ex –  carrot, radish, beetroot, turnip, dahlia.

From stem – Some plants have buds on their stem surface.      When stem of such plants is cut into small pieces (stem cutting) and plant into soil a new plant grows.

          Ex- Rose, Hibiscus, money plant, Grass etc.

From leaves – Some leaves like bryophyllum have buds on their margins when these leaves fall down on a moist soil the bud can grow into a new plant.

 

                   

Kinds of plants on the basis of Life span (age) – 3-Types

Perennial plants: – Those Plants which live for a long time is called perennial plants.

Ex- banyan, neem, apple, mango

Biennial plants: – Those Plants which live for two seasons are called biennial plants.    

Ex: – carrot, radish.

Annual Plants: –Those Plants which live for one season is called annual plants.

Ex: – wheal, maize, paddy.

 

Kinds of plants on the basis of Climate

                    

 

Aquatic plants: – Those Plants which live in water is called aquatic plants. Ex- Lotus, Lilly

 

Desert plants: – Those Plants which live in desert is called desert plants.

 

 

Manures and Fertilizers: –     

Manures: – Those organic substances that are obtained by the microbial decomposition of plants and animals waste are called manure.

 

Why do we add manures and fertilizers in the soil?

Continuous growing of crop in the field causes deficiency of mineral nutrients in the soil. So, the manure is added to the soil to make up the deficiency of mineral nutrients.

 

Certain tips for a good and healthy crop yield

Use batter and healthy quality of seeds for sowing.

Prepare the land well before sowing.

Add manures and fertilizers to the soil.

Irrigate the plants properly.

Remove weeds from the field for the proper growth of plants.

Use insecticides or pesticides, to keep the plants pets free.

 

Fill in the blanks

1. During the early stages the embroy will get food from the cotyledons.
2. The bark of seed is called seed coat.
3. To break seed coat a new plant will emerge out of the seed is called embryo.
4. The plant having flower is called angiosperms (Flowering Plants).
5. The plant having seeds in cones is called gymnosperms (Non-Flowering Plants).
6. ……. And ……… are examples of dicot seed.
7. ……. And ……… are examples of monocot seed.

 

SHORT QUESTIONS ANWER

What is the importance of cotyledons for a plant?

Cotyledons provide food for the baby plant in the early stages of germination.

Why do plants scatter their seeds?

Plants scatter their seeds in order to ensure that they don’t grow to close to each other.

What is step farming?

When the crops are grown by cutting steps is called step farming. The people of hilly areas step farming into the mountains.

Describe the process of germination.

The process by which a seed grows into a new plant is called germination.

When the seed get all the necessary things like air, water, warmth, space and nutrients from the soil the process of germination starts.

Define agriculture. Write different stages of agriculture.

The practice of growing plants on a large scale for food or other purposes is called agriculture. The different stages are –

1. The field is ploughed.
2. Manure is added to the soil.
3. Seeds are sown.
4. The crops are irrigated (watered).
5. The crops are sprayed with chemicals called pesticides to protect them from pests.
6. The crops are harvested.