Question
Explain the various functions of blood.

Answer

Functions of blood are as follows:
  • It supplies oxygen to cells and tissues.
  • It supplies essential nutrients to cells, such as amino acids, fatty acids, and glucose.
  • It removes carbon dioxide, urea and lactic acid (waste products)
  • Its white blood cells have antibodies which defend us from infection and foreign bodies.
  • It has specialized cells, such as platelets, which help the blood to clot (coagulate) when we are bleeding.
  • It transports hormones-chemicals released by a cell in one part of the body that sends out messages that affect cells elsewhere in the body.
  • It regulates our acidity (pH) levels.
  • It regulates our body temperature. When the weather is very warm or during strenuous exercise there will be increased blood flow to the surface, resulting in warmer skin and faster heat loss. When environmental temperatures drop, blood flow focuses more on the important organs deep inside the body.

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