Living Things and the Environment.pptx Grade 3 Science

Science 3

1. Living Things and the Environment

2. Every living thing on needs some basic things to live and grow.

3. Basic needs of livings things water All living things need water to live. Many plants and animals live in water.

4. air All living things need oxygen in the air to breathe. Plants need carbon dioxide in the air to make their food. Needs of a Living Thing

5. food L iving things need energy to live and work. We get this energy from the food we eat. Needs of a Living Thing

6. sunlight It is a source of energy. It helps the plants to make food. It also gives plants and animals heat and light. Needs of a Living Thing

7. r ight temperature Every living thing needs a certain temperature to grow and live. Needs of a Living Thing

8. The amount of these needs is different for different types of living things.

9. A lotus plant lives in water and needs lots of it to grow, w hile a cactus plant can survive in deserts where there is no or very little water.

10. All living things depend on each other. Some ways in which animals depend upon plants are:

11. Animals depend upon plant for food. Many animals eat plants directly while some eat plant-eating animals. Animals depend upon plant for oxygen. Many animals depend upon plants for their shelter.

12. Plants depend upon animals to spread their seeds. The seed sticks to the bodies of animals and spread around as the animals move. Plants depend on animals for carbon dioxide that they need to make their food.

13. Human beings also depend on plants and animals. We get food from them and other useful things like wool, honey, cotton and wood. We also depend upon plants for oxygen.

14. Living things also depend on many non-living things in the environment .

15. Human beings and animals depend on the air around them for the oxygen that they need to live. Plants also depend on air for carbon dioxide to make food and nitrogen to keep them healthy . Air

16. All living things need water. They depend on the natural sources of water in their surroundings for different uses. Water

17. All living things depend on the Sun for light and heat . Plants make food with the help of sunlight through process called photosynthesis. Sun Photosynthesis

18. Plants depend upon soil for growth . It provides nutrients and water to the growing plants. Some animals such as rabbits, ants, snakes, and rats depend on soil for shelter.

19. Imagine if living things continue to live forever and reproduce. What will happen ?

20. There would be no enough space and we would not have enough food. So, it is important to keep a balance in the environment.

21. These things keep the balance in our environment: In a food chain, a plant is eaten by an animal who is eaten by another animal, and so on. This makes sure that one type of plant or animal does not become to many.

22. These things keep the balance in our environment: Human beings and animals breathe out carbon dioxide which is taken by plants. Similarly, plants produce oxygen that we need to breathe. Oxygen and Carbon Dioxide

23. These things keep the balance in our environment: The water cycle keeps a balance in the levels of water in the environment. water Water heats and goes up Water cools and falls back on Earth rain

24. Did you know ? Increasing human population and pollution due to various human activities are 2 major factors affecting the balance of the environment in today’s time. The End 