Question

Explain the importance of tightly regulating plasma volume, osmolarity, and pH. Why does it matter that homeostasis is maintained? What role do the kidneys play in homeostasis?

Answer 1

Organisms can only function if their internal conditions are kept within a specific range.this is called homeostasis, Many homeostatic mechanisms work continuously to maintain stable conditions in the human body, if homeostasis is not maintained than toxic substance starts accumulating, the body's balance gets disrupted, this all could result in state of disease, or even death. Since, the intracellular space constitutes the largest body compartment, holding approximately two thirds of body fluid, changes in water homeostasis predominantly affect cells, Water levels and mineral salts in the blood are controlled to protect animal cells by stopping too much water from entering or leaving them. The concentration of water and salts is the same inside and outside of the cells. If body cells lose or gain too much water by osmosis, they do not function efficiently. water excess leads to cellular swelling, and water deficit leads to cellular shrinkage.

The osmolarity, the amount of solute per unit volume, of bodily fluids is tightly regulated. Extreme variation in osmolarity causes cells to shrink or swell, damaging or destroying cellular structure and disrupting normal cellular function.Regulation of osmolarity is achieved by balancing the intake and excretion of sodium with that of water, if the osmolarity increases it can cause blood pressure, on the other hand if osmolarity decreases than blood pressure can increase, so it is very important osmolarity of blood is maintained

Regulation of body fluid pH is one of the most important physiological functions of homeostasis, because activity of most chemical reactions via enzyme proteins is dependent on fluid pH.The normal physiological pH of mammalian arterial blood is strictly maintained at 7.40,.a decrease in the normal pH results in acidosis. The body fluids of diabetic patients are chronically acidic and exhibit characteristic ketoacidosis caused by an increased level of ketone bodies in the blood, on the other hand if pH in increased it can result in alkalosis, both acidty or alkalosis, if immediately not maintained it can result in fatal conditions.

Kidneys have important functions that maintain homeostasis in the body including regulating acid-base balance, the concentration of electrolytes, controlling blood pressure, and secreting hormones. the kidneys are the main organs for regulation of pH in the body. They do this by recovering and regenerating bicarbonate (HCO3–) from urine and excreting hydrogen ions (H+) into the urine. A low level of water in the blood triggers retention of water by the kidneys. The kidneys produce more concentrated urine, so less water is lost from the body and vice-versa. The kidneys synthesize two important hormones that help support homeostasis, erythropoietin and renin. Renin secreted by kidney works through Renin-Angiotensin-aldosterone mechanism to regulate blood volume, blood osmolarity and blood pressure