Describe biological water cycles.
The organisms get water from and return it to the global water cycle. Plants absorb water from the soil or water reservoir and add it to the air in vapour form by a process called transpiration. Water transpired by trees cools the surrounding air. Animals take water from the water reservoir or with food and return it to the air and vapours by respiration or to the soil by excretion. Mammals also excrete water as sweat which evaporates from the water bodies. Water is added to the environment by the death and decay of organisms. Water vapour formed by transpiration and respiration form clouds and enters global water cycle. Rain adds water to the soil and reservoir for reuse by plants and animals. This completes the water cycle.