Question

Human blood maintains homeostasis in the internal environment of the body by
A) Replenishment of oxygen and elimination of Carbon dioxide
B) Replenishment of nutrients and oxygen and elimination of metabolic wastes from the extracellular fluid.
C) Maintenance of ion concentration in the blood and body fluids by eliminating nitrogenous wastes.
D) Maintenance of blood sugar level and conversion of amino acids into urea and destruction of worn out RCBs.

Answer 1

Maintaining the internal environment by maintaining body equilibrium, which results in proper functioning of the body is termed as homeostasis. Human blood has a major role in maintaining the homeostasis of our internal environment.

Complete answer:
Let's look through the options for finding the correct answer.

Option A: Replenishment of oxygen and elimination of carbon dioxide is done with the help of lungs by respiration.Therefore, this is the incorrect option.
Option B: Replenishment of nutrients and oxygen and elimination of metabolic wastes from the extracellular fluid by the human blood helps in the maintenance of homeostasis in the internal environment of the body. Blood acts as a vehicle which carries nutrients and essential elements like glucose, potassium, sodium, proteins, hormones and enzymes. Respiratory gases are also transported through the blood, which is one of its primary functions. It carries cellular wastes such as carbon dioxide and lactic acid away from the cells. Regulation of body temperature and maintenance of acid base balance is also done by the blood. Therefore, this is the correct option.
Option C: Although blood has a role in maintaining ionic concentration, elimination of nitrogenous wastes is not the primary function of blood which links to maintaining homeostasis of the internal environment. Therefore, this is the incorrect option.
Option D: Maintenance of blood sugar level is done by pancreas, conversion of amino acids to urea occur at kidneys and destruction of worn out RBC s occur at the spleen. Blood has no direct role in these processes. Therefore, this is the incorrect option.

Thus, the correct option is( B) Replenishment of nutrients and oxygen and elimination of metabolic wastes from the extracellular fluid.

Note: Other than blood, organs which maintain homeostasis are:
(i) Hypothalamus and pituitary gland
(ii) The lungs
(iii) Liver
(iv) Pancreas
(v) Kidneys
(vi) Skin
Organ systems also work together to maintain internal homeostasis. Eg: Cardiovascular, urinary and lymphatic system together helps in controlling water balance of the body.