Although plants and animals are both living things, they differ from one another in some ways. The principal differences between them are:

Form and structure
Metabolism
Irritability

The body of animal is rather constant, while plants, body is often variable. Animal organs are mostly internal, while plants are added externally. The cells of animal are within delicate membranes and the tissues are are both in solutions containing sodium, potassium, and chlorine. While in plants, cells are within thick rigid walls of cellulose and sodium chloride is toxic. Animal growth producing changes in proportion of body parts with age, while growth of plants is usually terminal and often.

Animals depend on plants and other animals for their food. Food is digested and rearranged chemically within the body. Oxygen is needed for respiration. The end products of metabolism are carbon dioxide, water and urea. While plants manufacture their own food by photosynthesis.

Most animals have nervous system and they can respond faster to stimuli. Plants don't have nervous system and they respond slower to stimuli.