What is food? What are its main functions, and is there any source of food except plants and animal?

Food is the nutritious substance that living organisms eat to obtain energy. The energy obtained from food is required for the growth and repair of the body and to perform various activities.

Living organisms consume food for growth, survival, prevention of diseases, repair, and reproduction.

Main functions of food are as follows:

1. Provide Energy.

2. Growth and Development.

3. Repair and maintenance of the body's cells.

4. Prevent and fight infections.

5. Keep us alive, & active.

Our primary sources of food are plants and secondary animals. We get most of our food from plants & animals.

Thus there are two kinds of food,

1. Plant-based food,

From plants, we get food from different parts such as roots, leaves, stems, flowers, and fruits.  For example-  vegetables, fruits, cereals and pulses, oil, sugar, oil, and spices.

Foods that we get from animals. For example- milk, meat, and eggs.

But, there are some sources of food that are not collected from any plants or animals, rather they are invented by humans by mixing different types of chemicals and some exist naturally on Earth.

For example - baking soda, baking powder, vinegar, salt, etc.

We also eat some species of fungi which doesn't belong to any plant or animal kingdom.

For example, the most popular fungi that we eat is 'mushroom'.