Nutrition in plants cbse class seven science

Nutrition in plants

1. Previous 6th grade Science Our Food Components of Food Carbohydrates Fats Proteins Vitamins Minerals The Main nutrients in our Food we eat 7 t h Grade General Science

2. Identify the main nutrients present in the pictures given below 1 2 3 4

3. Nutrition The process of taking food by an organism and its utilization by the body

4. Chapter 1 – Nutrition in Plants The mode of nutrition in which an organism prepare its own food from simple raw materials is called Autotrophic nutrition Example : All Green Plants(Producers) can prepare their own food with the process called Photosynthesis Autotrophic Nutrition: Auto means Self trophic means nourishment

5. PHOTOSYNTHESIS The process by plants prepare their own food using water, carbon dioxide and mineral salts in the presence of sunlight and chlorophyll is called Photosynthesis

6.  Let us discuss each of them 

7. Chlorophyll is found in structures called CHLOROPLAST Each Chloroplast contains stacks of THYLAKOIDS called GRANA(singular Granum ) Each Thylakoids is a disc that contains chlorophyll and helps in the absorption of sunlight The aqueous space where G rana are arranged is called STROMA Fig: Cross section of Chloroplast

8. Light energy trapped by the chlorophyll is used to convert raw material into sugar SUNLIGHT CARBON DIOXIDE Plants obtain carbon dioxide and release oxygen through pores called STOMATA

9. The opening and closing of the pores of stomata are regulated by GUARD CELLS When guard cells become turgid(Swollen), Stoma opens allowing CO 2 to enter the leaf The Stoma closes when the guard cells becomes Flaccid(Shrunken)

10. WATER The plants absorb water from soil through root system(primary root, secondary root and root hair) Water and Minerals are absorbed by the root hairs ? But How water is transported to leaves and stem

11. Phloem transports the food(Starch) to different part of plant Xylem transports the water and minerals to different parts of the plant

12. Experiment to show that chlorophyll Is necessary for photosynthesis

13. Experiment to show light is essential for photosynthesis Experiment to show that carbon dioxide is necessary for photosynthesis

14. Fill in the blanks with correct word s The process of taking food by an organism and its utilization by the body is known as________(Photosynthesis/Nutrition) 2. Green plants are ____________(autotrophic/heterotrophic) 3. _______(O 2 / CO 2 ) is released in the process of photosynthesis. 4. Chlorophyll is found in___________(Chloroplast/Stomata) 5. Plants obtain carbon dioxide through_________(Stomata/guard cells) 6. ________(Xylem/ Pholem ) transports food to the different parts of the plant. Mini Assignment

15. Heterotrophic : Hetero mean Other trophos mean nourishment Heterotrophic Nutrition The mode of nutrition in which an organism cannot prepare their own food and depends on other organisms for food is called Heterotrophic nutrition. Example: All non green plants

16. Parasitic Plants  Parasitic plants derive some or entire nutritional requirements from another living plant  The plant from which a parasite derives its nutrition is called a HOST Dodder plant ( amar bel ) does not have green leaves and hence depends on its host for food Note In a parasitic relationship, the parasitic plant always benefits, but the host is harmed. Parasitic plants rarely kill the host plant as this would not be advantageous to them

17. Mistletoe is another parasitic plant has green leaves to synthesis food, but depends on the host plant for water and minerals Sandalwood tree is partially parasitic. It can photosynthesize but traps the roots of other species for water and inorganic nutrients Example of Parasitic plants

18. Saprophytic Plants Saprophytic plants or saprophytes derive their nutrition from dead and decaying organic matter

19. Indian Pipe Coral root Saprophytes lack of chlorophyll, so they cannot photosynthesize. Roots of saprophytes have fungi that secrete digestive juices on the organic matter. These juices convert organic matter into nutrients which are absorbed by fungi and are later used by plants as food

20. Insectivorous Plants Insectivorous plants have a poorly developed root system and often grow in nitrogen-deficient conditions. They obtain food by trapping, digesting and absorbing nutrients from prey such as insects, spiders etc Examples for Insectivorous plants are  Venus fly trap usually found in bog soil Their leaves are open wide and bear shot, sensitive hair. When anything touches the hair, the two folds of leaves shut, trap within less than a second

21. Bladderworts have tiny bladder like structures on their underwater leaves. Once any tiny aquatic animals trapped inside, the plant absorbs the animal nutrients using digestive juice Pitcher Plant leaf is modified as tubular pitcher like structure that acts as trap for the prey. Once the prey falls inside, the fluid containing digestive juice will digest the prey

22. Sundew plant are usually found in nutrient-deficient boggy area. When insect land on sticky leaves , it gets stuck to the sticky substance(mucilage) and digest it Symbiotic Plants A situation in which two dissimilar organisms live together in close association for mutual benefit is called Symbiosis. Certain plants live in a symbiotic relationship for their survival. Those symbiotic relationship of plants are called Symbiotic Plants

23. Examples for symbiotic plants are Lichens – Symbiotic association between algae and fungi to share food and other resources The fungi obtain carbohydrates from alage , which are photosynthetic and contribute the green colour to lichen. In return, the fungi help alage to grow in harsh conditions

24. Leguminous plant such as pea or bean have root nodules contain nitrogen-fixing bacteria called Rhizobium . Rhizobium helps in converting atmosphere nitrogen to compounds such as ammonia that are usable by the plant

25. How Nutrients are replenished in the soil

26. Mini Assignment Give one word of the following The organisms which derive their food from other organism A plant which derives some or it entire nutritional requirement from another living plant 3. Plants which capture prey like insects, spider and mites 4. Plants which derive their nutrition from dead and decaying organic matter 5. Plants which are part of a symbiotic association

27. THANK YOU