Category: O level Integrated Science

The sun is the ultimate source of energy for all living things. Green plants can use energy from the sun to make food in a process called photosynthesis. All other organisms directly or indirectly depend on the food made by plants. Photosynthesis produces carbohydrates and oxygen. Plants require other nutrients such as proteins, fats and mineral salts. Plants are affected by pests and diseases. Pests and diseases can be controlled using chemical methods and cultural methods.