1 – Water is absolutely essential to the human body’s survival. Water is involved in all bodily functions: digestion , assimilation , elimination , respiration , maintaining temperature and the strength of all bodily structures. 2 – Water helps to maintain healthy body weight by increasing metabolism and regulating …
1 – Water vapour is practically always present in the air in various quantities depending on conditions. When warm air rises , it expands and cools. Cool air can’t hold as much water vapor as warm air , so some of the vapor condenses onto tiny pieces of dust …
1 – Rain falls from clouds in the sky in the form of water droplets , this is called precipitation. 2 – Water can also fall from the sky in the form of hail and snow. 3 – Most of the Earth’s surface is covered with water — and …
1 – As the sun warms the Earth’s surface , the atmosphere warms too. Warm air , which weighs less than cold air , rises. Then cool air moves in and replaces the rising warm air. This movement of air is what makes the wind blow. 2 – Wind …
1 – Ocean waters serve as a source of food and valuable minerals. 2 – Other products of the oceans are also used. For example , pearls taken from oysters are used in jewelry , and shells and coral have been widely used as a source of building material. …
1 – Rivers begin at their source in higher ground such as mountains or hills , where rain water or melting snow collects and forms tiny streams. 2 – As the river flows downstream , it gains more water from other streams , rivers , springs , added rainfall …
1 – Lakes are water-bodies formed naturally whereas reservoirs are artificial water bodies constructed by humans , either by damming a flowing river or by diverting water from a river to an artificial basin. 2 – A lake usually contains freshwater but some can be saltwater. 3 – Lakes …
1 – A glacier is formed from compacted layers of snow , that slowly deforms and flows due to gravity. 2 – Glaciers play a crucial role in storing up and slowly releasing water , making it available during the dry season when there is almost no rain. 3 …
1 – Around 20 percent of the Earth’s surface is covered with mountains. 2 – There are mountains and mountain ranges in the ocean. Many islands are actually the tops of mountains. 3 – Half of the world’s population depends on mountain water. The mountains are a store house …