Usefulness of plants and human affairs (utility)
Food
Plants are the main source of food for humans. Plants, unlike humans and animals, manufacture their own food. They do so by the process known as photosynthesis in their green leaves by use of sunlight. They can convert and store the light energy in the form of carbohydrates. This process takes place in the leaves (chlorophyll) by use of carbon-dioxide and water.
From this manufactured food, they consume some of it and store the remaining. This is stored in the form of fruits, seeds, tuberous roots, etc. This fruits and other parts of plants are consumed by humans. The food is in the form of vegetables, fruits, grains, cereals, leaves, seeds, mushrooms, etc.
Clothing
Plants are the largest providers of textile and fabric material. These materials are eco-friendly, compatible and less expensive. So they are used for making cloth and bedding material which is required by humans.
Furniture & Shelter
Plants are the important source of furniture. The plant wood is used to build houses and also to make other furniture items. We use wood for the purpose due to its features like durability, stylish finishing, resistance to temperature changes, etc. The trees like teak, neem, red sandal, etc. are good sources of wood for making doors, chairs, shelves, tables, etc.
Even the presence of plants around the area of human life relieves stress. Hence we see many people growing small plants in their household to get fresh air and also give naturalness.
Flowers
Flowers are used widely by humans. They are used for beauty, to convey feelings and also for their fragrance. In some countries, they worn as garlands and even in the hair on the head for beauty. While some use them to convey their love to their beloved ones. They are also used to produce fragrance, and even their scent is extracted for daily use.
Natural pesticide
Plants are also the source of insecticides and pesticides. Using artificial pesticides are harmful to the environment. They may even enter food causing health issue to human and animals. Using these naturally derived pesticides are safe. They degrade with time and even do not harm the soil. Ex: Pyrethrin (as Mosquito repellant), Neem, bacteria, etc.
Biofuels
Some plants are also grown for the sake of bio-fuels. The plant’s fuel is less toxic since it does not emit harmful gasses and also less expensive. Even the plant waste is used to generate electricity.
Economic contribution
Plants are great contributors to an economy. Many countries rely on agriculture as one of the main sources of revenue. Plants are responsible for the production of food, cosmetics, drugs, cloth, honey, gum, tannins, essential oils (perfumes), alkaloids, resins, etc. which are all money yielding. So plants provide a great contribution to economic growth. Even now many countries economies are primarily dependent on plant products.
Importance of Plants in nature
Environment and the climate are interlinked mainly with plants. The presence of plants influences Rainfall, humidity, and temperature. Cutting down plants also imbalance the environment which will indirectly affect human life.
In cities and towns, there is a rise in gaseous pollution like(CO2, CO, SO2, etc.). So city environments are highly polluted and unsafe for living. This is due to automobiles and factories ejecting toxic gases and also reducing the healthy oxygen ratio of air. Air pollution causes diseases of various types. So growing plants on the roadside, parks, etc. helps minimize the gaseous pollution. For the benefit of plants oxygen, they can even be grown in office, residential areas, education institutes, etc. For this, we can use low maintenance plants like indoor potted plants, hanging plants, etc.
Miscellaneous benefits
They are the source of essential oils which are used in perfumes. Their material is used for making beverages like wine, beer, etc. Other items like paper, bio-diesel, bio-manure are also obtained by use of plant material. So they contribute to all the types of living beings either big or small, on land or water. But given the vast importance of plants to human, we need to strive for plant conservation.