1. Water from rivers, lake, ponds and soil evaporates into water vapour and rises into the atmosphere. Water vapour is also released into the atmosphere through respiration, slant transpiration and the burning process. The water cycles is the continuous process of water movement on the earth to sustain water quantity.

2. The atmosphere is a layer of air that surrounds the earth. It controls the earth’s temperature. The ozone layer in the atmosphere protects human being and living things from the danger of Ultra- violet rays(UV)

3. Respiration occurs inside the cells. During this process, oxygen is used to burn up the food consumed. As a result, carbon dioxide, water vapour and energy are released. RESPIRATION

4. Water vapour is also released into the atmosphere through burning and decomposition of organic substances such as wood and animal carcasses. THE BURNING PROCESS

5. The loss of water vapour by plants to the atmosphere. Transpiration takes place during the day time TRANSPIRATION