1. We need plants for food:
The food we eat consists mainly of cereals, fruits and vegetables. Cereals are grains of plants like rice, wheat, oats, barley, maize and rye. The sweet and fleshy part of the plant that contains the seed is called a fruit, e.g., apple, orange and banana.
Parts of the plants that are eaten other than the seeds and fruit, such as leaves, roots and stem are called vegetables. Potato, tomato, cabbage etc. are vegetables. We can see we get all the main components of our diet from plants. We also get tea, coffee, sugar and spices from plants.
2. We need plants for materials:
We get materials like wood, fibre, gum and rubber from plants. We need wood for furniture, construction, making paper and as fuel. Cotton fibre that we get from the cotton plant is used for making clothes and fabric. We need rubber for making tyres, erasers, toys and many other things. It is also extracted in a raw form from rubber trees. The gum we get from acacia trees is sued widely as an adhesive.
3. We need plants for medicines:
Plants are the source of many important medicines used for treating diseases that afflict man. Quinine, a medicine used to treat malaria, is extracted from the bark of the cinchona tree.
Plants like tulsi, neem, garlic and mint are used as effective home remedies to treat common ailments like cold, cough, indigestion etc.
4. We need plants to keep the balance of oxygen in the air:
Animals and human beings breathe in oxygen and breathe out carbon dioxide. If there was no counter process to balance this phenomenon, the oxygen in the air would soon finish ! But we know that green plants in our environment take in carbon dioxide and give out oxygen during the process of photosynthesis. Thus plants re very important because they keep the quantity of oxygen in the air balanced.