Answer
Transport Functions:
• Transport of hormones, chemical substances, nutrients, vitamins etc.,
• Transport of oxygen and carbon dioxide
Protective Functions:
• Antibodies
• Blood cells like monocytes
Regulatory Functions:
• Temperature regulation
• Cellular hydration
Work Step by Step
Transport Functions:
• Blood is a transport medium for hormones, chemical substances, nutrients, vitamins etc., Hormones which are secreted by endocrine glands like hypothalamus, thyroid, pituitary etc., are transported to target organs by blood. Also, the nutrients which are absorbed in gastrointestinal tract are transported by blood to various body parts
• Blood carried oxygen from the lungs to tissues in the form of oxyhemoglobin.
The carbon dioxide which is formed in tissues after metabolism is carried to the lungs by blood. It is carried mostly in the form of bicarbonate whereas some amount is also transported in the form of carbaminohemoglobin
Protective Functions:
• Blood contains antibodies which act against foreign antigens and protect the body. This type of immunity is known as humoral immunity. It is responsible for detection and destruction of invading foreign antigens
• Blood contains cells like monocytes which migrate to the tissues and get converted to macrophages. These macrophages are responsible for inducing an immune response. They travel to the site of infection and are responsible for immune response actions like inflammation. Blood also contains cells and chemicals that take part in non-specific defenses of the body
Regulatory Functions:
• Blood absorbs the heat produced by metabolic reactions inside the body. It then conducts the absorbed heat from interior of the body to the surface through blood vessels. This occurs through two processes known as vasodilation and vasoconstriction. Vasoconstriction preserves body temperature whereas vasodilation facilitates heat dissipation from body.
• When there is loss of body water due to dehydration, the blood volume decreases and causes hypovolemia. This activates many mechanisms to increase blood volume and water levels in body. Thus, it helps in maintaining cellular hydration by keeping a check of water homeostasis.
