Explain why the presence of liquid water on the planet is one of the conditions for life.

Water is the habitat of a huge number of living organisms.
Thanks to water, in nature there is a transfer of substances from soil to plants, from land to rivers, lakes and oceans, from the atmosphere to land, nutrition of living organisms of these systems and the removal of their waste. The water shell of the Earth (hydrosphere) and, accordingly, life on the planet is practically not interrupted on the surface of the planet, all its components are combined into a single whole thanks to water.
For life on Earth, such a property of water as its high heat capacity is also extremely important. Water determines the stability of the temperature regime on the planet. In the daytime, as well as in summer, water masses slowly heat up, while absorbing a lot of heat, which does not allow the air to heat up very much. At night and in winter, on the contrary, the water masses slowly cool down, releasing previously accumulated heat, which prevents the air from cooling excessively.
Another remarkable property of water is its extremely high dissolving power, it is a universal solvent for a huge amount of chemicals, an environment in which all life processes take place. Water ensures the delivery of nutrients and oxygen to all cells of the body, protection and buffering of vital organs, regulation of body temperature, helps in converting food into energy, assimilation of nutrients by organs, removal of toxins and waste in the process of life, and a variety of other functions.

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