All the living organisms i.e. plants and animals require food. These organisms need to take food by different modes of nutrition in order to obtain energy as well as the materials for growth and repair of damaged parts of the body. Nutrition is the process of taking food by an organism as well as the utilization of this food by the organisms. Let’s know more about these modes of nutrition.
Modes of Nutrition
We all know that the plants can make their own food through the process of photosynthesis, however, animals and human beings cannot make food for themselves. They obtain food from plants and other animals that feed on plants. Thus, it is seen that human beings and animals depend on plants for their food – somewhere directly or indirectly.
Green plants are autotrophic and synthesize or make their own food by the process of photosynthesis. They do this with the help of carbon dioxide and water in the presence of sunlight. Photosynthesis is the process by which the green plants make their own food ( like glucose ) from carbon dioxide and water by using sunlight energy in the presence of chlorophyll.
On the basis of their modes of nutrition, all the organisms are divided into two main groups – autotrophs and heterotrophs. Their corresponding modes of nutrition are known as the autotrophic and heterotrophic mode of nutrition.
Autotrophs (or Autotrophic Modes of Nutrition)
Those organisms that can make food themselves from simple substances like carbon dioxide and water are called autotrophs. Their mode of nutrition is referred to as autotrophic. They do this by the process of photosynthesis.
All the green plants are called autotrophs. This is due to the fact that the green plants make their own food from very simple substances like carbon dioxide and water that is present in the surroundings. They do this by the process of photosynthesis.
We can also say that the green plants have an autotrophic mode of nutrition. These green plants contain a green pigment called chlorophyll which further helps in making food by absorbing energy received from the sunlight. Majorly the green plants synthesize their own food – not only for themselves but also for the non-green plants, animals as well as human beings.
Heterotrophs (or Heterotrophic Modes of Nutrition)
Heterotrophs are referred to those organisms which cannot prepare their own food. They are dependent on green plants or animals for their food. Their mode of nutrition is known as the heterotrophic mode of nutrition. All the non-green plants and animals, inclusive of human beings, are called heterotrophs.
The non-green plants lack chlorophyll which is necessary to carry out the process of food referred to as photosynthesis. Therefore, they depend on other organisms i.e. plants and animals in order to obtain food.
The non-green plants, for example. Fungi, yeast, mushroom, bread mold, are called heterotrophs. They have a heterotrophic mode of nutrition. Therefore, all animals like dogs, cats, cow, buffalo, lion, tiger, deer as well as human beings are called heterotrophs. Their mode of nutrition called ‘ heterotrophic mode of nutrition ‘.
Solved Question for You
Q: Differentiate between autotrophs and heterotrophs.
Ans: Green plants are called autotrophs as they prepare their own food from simple substances. However, animals and most other organisms are called heterotrophs as they take in ready-made food prepared by the plants.