What is A Plant? First of all, what is a plant? A plant cannot be defined in a statement without excluding some plants, or including some animals. A plant is characterized by being able to produce its own food from water, minerals, and carbon dioxide from a process known as photosynthesis. Photosynthesis uses the energy from sunlight and changes it to a form the plant can use, with the help of chlorophyll, a green pigment molecule in a plant that converts light energy into a form of energy that the plant can use. The lack of nervous and sensory systems and the lack of organs of locomotion also charac