2.Write the steps of nutrition. State the modes of nutrition
Answers
Plants and animals do not obtain food by the same processes.
Plants and some bacteria have the green pigment chlorophyll to help synthesize food, while animals, fungi and other bacteria depend on other organisms for food.
Based on this, there are two main modes of nutrition: autotrophic and heterotrophic.
1. Autotrophic nutrition:
The term ‘autotroph’ is derived from two Greek words—autos (self) and trophe (nutrition). In autotrophic nutrition, an organism makes its own food from simple raw materials.
A Summary of Nutrition in Green Plants
Photosynthesis:
Green plants, which are autotrophic, synthesize food through the process of photosynthesis. Photosynthesis is a process by which green plants, having chlorophyll, synthesize the simple sugar (glucose) from the simple raw materials water and carbon dioxide using the energy of sunlight. Oxygen is released in this process.
The sugar produced is stored in the form of starch in plants. (In animals food is stored in the form of glycogen.) These food reserves provide energy as and when required by the organism. Since autotrophic plants are able to produce food, they are also known as producers.