2. When standing, a small amount of carbon dioxide will be dissolved in water to generate carbonic acid;
3. But if the water is allowed to dry for a few days, microorganisms and algae will also enter the water, and many anaerobic microorganisms and bacteria will multiply and the water will stink.
Extended data:
Effects of water on human body:
1, dissolution and digestion function
Water has strong solubility and ionization ability (water molecules have strong polarity), which can make water-soluble substances exist in dissolved state and electrolyte ion state. Even some fats and protein can be dissolved in water under proper conditions to form emulsion or colloidal solution.
2. Participate in metabolic function
In the process of metabolism, substance exchange and chemical reaction in human body are all carried out in water. If the human body is short of water for a long time, the metabolic function will be abnormal, which will slow down metabolism, accumulate too much energy and fat, and make people obese.
3. Carrier transportation function
Because water has good solubility, strong fluidity and is contained in various tissues and organs in the body, water acts as a carrier of various nutrients in the body.
4, adjust the inhibition function
Water has a high specific heat and can regulate body temperature. Water can also improve the circulation of body fluids, regulate muscle tension and maintain the osmotic pressure and acid-base balance of the body.
People's Health Network-Did you smell the water overnight? These four reasons will never occur to you.