Plants obtain energy from the sun through a process called photosynthesis, where they convert sunlight into chemical energy stored in carbohydrates. Animals, on the other hand, obtain energy by consuming other organisms, such as plants or other animals, and breaking down their organic molecules through processes like respiration and digestion. In this way, plants are able to directly produce their own energy from the sun, while animals must consume other organisms to obtain the energy they need to grow and survive.