All living creatures need food to survive and grow, and plants are no exception. Unlike human beings and animals, plants make their food without moving anywhere. They are able to do so with the help of their leaves and roots in the presence of sunlight. This process of making food for themselves is known as photosynthesis in plants. Comprised of two words, “photo” meaning “light” and “synthesis” meaning “putting together,” photosynthesis is a chemical reaction that relies on some chemical reactants and stomata in the leaf for carrying out the entire process.
When a seed germinates into a sapling, the stored reservoirs of energies are used up by the sapling. The plant must create its own energy in order to survive. Photosynthesis is the process by which new lease of energy is made available to the plant. For photosynthesis, plants need light, water, carbon dioxide and chlorophyll. The chlorophyll converts water from soil and carbon dioxide from air into oxygen and sugar in the presence of sunlight.
Oxygen is then released into air through stomata (the tiny pores on the underside of leaves) into the environment while the sugar is used up and stored by the plant as its food.
Since a plant cannot survive without food, photosynthesis becomes a crucial process for plants. Photosynthesis is not only crucial for plants, it is equally important for human beings as well, because it leads to release of oxygen and it makes glucose in the plant for their consumption. The glucose stored by plants is consumed by human beings and animals in the form of various vegetables and fruits and other edibles.
In gist, plants need photosynthesis because it makes the energy of the sun available to them for nourishment and growth.