NUTRITION

By Er. Anoop Dhiman4 Comments

NUTRITION

  1. MEANING OF NUTRITION- Nutrition is a process of intake nutrients by an organism as well its utilization to obtain energy.

NOTE-Nutrients are the substances which an organisms obtain from its surrounding and uses it as a source of energy.

For Example- Carbohydrates, fats , proteins, vitamins etc.

MODES OF NUTRITION

Modes of nutrition can be classified as

  1. AUTOTROPHIC MODE OF NUTRITION

In autotrophic mode of nutrition Organisms make their own food by using simple inorganic materials like CO2 and water  in the presence of sunlight.

For example- All green plants.

  1. HETEROTROPHIC MODE OF NUTRITIONS

In heterotrophic mode of nutrition, Organisms do not make their own food, they depends on other organisms for their food.

All the animals, most of the bacterial, fungi and non-green plants have heterotrophic mode of nutrition.

TYPES OF HETEROTROPHIC MODE OF NUTRITIONS

There are three types of heterotrophic mode of nutrition.

  • (i) Saprotrophic mode of nutrition
  • (ii) Parasitic mode of nutrition
  • (iii) Holozoic mode of nutrition

 

(I)SAPROTROPHIC MODE OF NUTRITION

In this mode of nutrition organisms obtain their food from dead and decaying organic matter of plants and animals.

For example- Rotten bread mold, Mushroom, Yeast and many bacteria.

NOTE-Saprotrops break down the complex organic molecule into simpler substances outside the body using enzymes.

(ii) PARACITIC MODE OF NUTRITIONS

In Parasitic mode of nutrition organisms obtain their food from the body of other organism without killing them.

For eg- Lice, Liver fluke,  Tapeworme.t.c

NOTE-

  • The organism which obtain food is called
  • The organism which provide food is called Host

(iii) HOLOZOIC MODE OF NUTRITIONS

In holozoic mode of nutrition, Organisms intake complex organic food by the process ingestion. The ingested food is digested and then absorbed in the body of organisms. Absorbed food is further assimilated and undigested food is thrown out of the body.

For example-Human being, cat , dog , amoeba, fish etc.

Answers the following questions

  1. Why nutrition is required?
  2. Write the mode of nutrition of the following organisms. (a) Liver Fluke (b) Green plants (c) Rotten bread mold (d) Human Beings