Class 7 Science Chapter 1: Nutrition in Plants - Notes PDF

Nutrition in Plants is chapter 1 in the NCERT class 7 Science book. Notes for class 7 Science chapter 1 is provided here to assist students with quick exam preparation for the CREST Science Olympiad (CSO) for class 7 and various similar competitions. These notes, which are specifically designed for class 7 nutrition in plants are written in a very precise style that helps students to learn all the topics covered in this chapter before the exam fearlessly.

Class 7 Science chapter 1 pdf is also available for free download which makes it easier for students to comprehend the concepts later in several conducted examinations.

Class 7 Science Chapter 1: Nutrition in Plants - Notes

Nutrition is the process by which food is consumed and utilized by the organism. All organisms require food to function properly. Food contains a variety of nutrients such as carbohydrates, proteins, fats, vitamins, and minerals. Food provides us with energy to grow, and repair the damaged parts of our body. Microorganisms, plants, and animals are examples of living organisms.

Plants obtain their nutrition through various modes. In plants, the mode of nutrition can be autotrophic or heterotrophic.

Autotrophs and Heterotrophs are two types of plants:

Autotrophic plants

They can synthesise their own food through the process of photosynthesis.

Heterotrophic plants

They cannot synthesise food on their own but depend on other organisms for their nutrition. Parasites, saprophytes, and symbiotic plants are all types of heterotrophic plants.

Autotrophic mode of nutrition

Photosynthesis

It is an autotrophic mode of nutrition. Photosynthesis is a process by which green plants can synthesize glucose from raw materials like carbon dioxide and water in the presence of sunlight and chlorophyll.

Requirements for photosynthesis

Facts about photosynthesis

1. Photosynthesis is used by all chlorophyll-containing plants, including algae, as well as some plants with red, brown, or other dominant pigments.
2. Leaves are considered as food factories of a plant.
3. Water and minerals are absorbed by the roots and transported to various parts of the plant.
4. Leaves have special structures called chloroplasts. Chloroplasts possess chlorophyll, a green colour pigment present in the leaf that captures energy from sunlight. Sun is the ultimate source of sunlight for all living organisms on earth.
5. In the presence of sunlight, plants synthesise glucose from carbon dioxide and water. Oxygen and water are released as by-products through the stomata during the daytime.
6. The food synthesised is transported to other parts of the plant for utilization and storage.
7. Glucose is a carbohydrates photosynthesis produces glucose, which is then converted into complex compounds such as starch and cellulose. Starch is stored in various locations throughout the plant.
8. Plants also prepare proteins with the help of nitrogen which is obtained from the soil.
9. Thus, the minerals dissolved in water are used to convert sugar synthesised into carbohydrates, proteins and fats.
10. These food components stored are the source of energy for other heterotrophic plants and animals.

Heterotrophic mode of nutrition

Heterotrophic plants do not possess chlorophyll. Therefore, they cannot produce their own food using the process of photosynthesis. Heterotrophic plants obtain food from other plants by following a parasitic, saprophytic or symbiotic mode.

Parasitic mode

Parasites are organisms that feed through a parasitic mode of nutrition. Parasites get their food from other living organisms. In a parasitic way of nutrition, plants depend on other plants or animals for their nourishment. Such plants are called parasites and the ones on which parasites depend are called hosts.

For example:

1. Mistletoe is another parasitic plant that depends on other organisms for its nourishment.
2. Cuscuta is a parasitic plant that develops special roots called haustoria.
3. Haustoria penetrate deep into host plant tissues and just absorbs their nutrients.

Insectivorous mode

These are plants with special leaves that are modified into special structures. These structures are capable of trapping organisms.

For example:

1. Nepenthes otherwise called pitcher plant has their leaves modified into pitchers closed with leaves. These have a network of fibres that entangle the trapped organism and later digest it by secreting some hydrolyzing enzymes to digest them.
2. Venus flytrap feeds on small animals and insects to stay alive. These plants, in particular, get their nitrogen from insects and small animals.

Saprophytic mode

Saprophytes are plants that have a saprotrophic mode of nutrition. Saprotrophs are plants that obtain their nutrition from dead and decaying organic matter. Saprotrophs secrete digestive juices onto dead and decaying matter, causing it to dissolve and absorb nutrients.

For example:

1. Indian pipe which is found on dead and rotting material inhabits fungus in its roots. These extend their mycelium and secrete enzymes to digest the decaying matter.
2. Coral roots are another type of plant exhibiting saprophytic nutrition.

Symbiotic mode

Symbiosis is the phenomenon in which two organisms maintain a relationship in order to benefit each other. To obtain nourishment, organisms in symbiotic mode form a special relationship with other organisms. Symbionts are organisms that are involved in this type of relationship.

For example:

1. Rhizobium bacteria and Leguminous plants are symbionts exhibiting symbiosis. Plants cannot utilize atmospheric nitrogen directly. Hence, leguminous plants establish a symbiotic relationship with bacteria like Rhizobium. Both the organisms of symbiotic relationships are mutually benefited. The leguminous plant provides shelter and nourishment for the bacteria and in turn bacteria fix atmospheric nitrogen to the plant.
2. Ruminant digestion is an excellent example of symbiosis. The caecum is a large sac-like structure located between the small and large intestines. The caecum's symbiotic bacteria aid in the complete digestion of cellulose. Ruminant stomach microorganisms aid in the digestion of cellulose, allowing the animal to provide shelter and nourishment. Microorganisms and ruminants have a symbiotic relationship.
3. Lichens form a very good example of a symbiotic relationship. Lichens are formed by the symbiotic relationship between algae and fungi sharing a single colony. The fungus provides water, nutrients and shelter in the form of a network formed by mycelium. Algae synthesise the food for the entire colony through the process of photosynthesis.

CREST Science Workbooks

As extra information, more familiar materials are also easily accessible for students to prepare for various subject matter like nutrition in plants for class 7. If one wants to ace their performance, all are welcome to upgrade their learning by considering CREST Olympiads workbooks. These workbooks have engaging content to make learning easy and enjoyable for class 7 students. It will also benefit them to practice and prepare for CREST Science Olympiad (CSO) and similar exams. Moreover, these notes are also helpful to crack standard school exams.

CREST Science workbook for class 7 can be considered by the students because of the following features -

1. Includes a detailed explanation of each topic with practice questionnaires.
2. Covers class 7 previous year paper of the CREST Science Olympiad.
3. Provides answer key for all questions

Proceed now to purchase Olympiad books.

Useful Links:

CREST Science Olympiad Book (First Chapter) PDF for Class 7 (Free Download)

CREST Olympiads Books for Class 7

Notes PDF for Nutrition in Plants for Class 7

To download the free notes PDF for class 7 Nutrition in Plants, click the link below.

Download Notes PDF for Nutrition in Plants for Class 7

Conclusion

With confidence, provided notes have served as a benefit for third-grade children to comprehend nutrition in plants for class 7. We made an effort to provide clear and precise master notes. We want to remind students to download the PDF because doing so will help them review the idea at a later time. We would greatly love to continue giving knowledge about several more Science-related topics in the bright days to come.