Understand the role of body fluids and circulation in human beings

This article is in continuation of the previous article that focused on human respiratory system. In today’s this article, we will discuss the body fluids and their circulation. All living cells have to be provided with nutrients, O2 and other essential substances. Also, the waste or harmful substances produced, have to be removed continuously for […]

This article is in continuation of the previous article that focused on human respiratory system. In today’s this article, we will discuss the body fluids and their circulation.

All living cells have to be provided with nutrients, O2 and other essential substances. Also, the waste or harmful substances produced, have to be removed continuously for healthy functioning of tissues. It is, therefore, essential to have efficient mechanisms for the movement of these substances to the cells and from the cells.

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• Different groups of animals have evolved different methods for this transport.
• Simple organisms like sponges and coelenterates circulate water from their surroundings through their body cavities to facilitate the cells to exchange these substances.
• More complex organisms use special fluids within their bodies to transport such materials.
• Blood is the most commonly used body fluid by most of the higher organisms, including humans, for this purpose.
• Another body fluid, lymph, also helps in the transport of certain substances.

Blood

Blood is a special connective tissue consisting of a fluid matrix, plasma, and formed elements.

Plasma

• Plasma is a straw-coloured viscous fluid constituting nearly 55 per cent of the blood.
• 90-92 per cent of plasma is water and proteins contribute 6-8 per cent of it.
• Fibrinogen, globulins and albumins are the major proteins.
• Fibrinogens are needed for clotting or coagulation of blood.
• Globulins primarily are involved in defence mechanisms of the body and
• Albumins help in osmotic balance.
• Plasma also contains small amounts of minerals like Na , Ca , Mg , HCO3 –, Cl–, etc.
• Glucose, amino acids, lipids, etc., are also present in the plasma as they are always in transit in the body.
• Factors for coagulation or clotting of blood are also present in the plasma in an inactive form.
• Plasma without the clotting factors is called serum.

— To be continued