CBSE Class 9 Answered

Animals have a digestive system, a feature that distinguishes them from plants. Plants produce their own food in a process called photosynthesis, during which they use sunlight to convert water and carbon dioxide into simple sugars. But animals, including humans, must take in food in the form of organic matter, such as plants or other animals. So they take in complex organic matter which should be broken down to simple molecules like glucose so that they can be absorbed and distributed throughout the body. This function is carried out by the digestive system.