Question

Describe in brief the structure of the kidney in humans and also describe its functions.

Hint:

The kidneys filter around 50 gallons of blood daily, maintaining homeostasis and detoxifying the body.

Answer 1

The human kidneys are bean-shaped, reddish-brown organs located on either side of the spine, just below the rib cage. Each kidney is about 10–12 cm long and weighs around 150 g. The kidney consists of three major regions:
1. Cortex – The outermost layer containing nephrons, the functional units.
2. Medulla – The inner region containing renal pyramids and loops of Henle.
3. Pelvis – The funnel-shaped cavity that collects urine before passing it to the ureter.
Functions of the Kidney:
The kidneys perform several vital functions:
1. Filtration of Blood – Nephrons filter waste, excess salts, and toxins from the blood.
2. Urine Formation – The kidney regulates water balance and forms urine.
3. Electrolyte Balance – Maintains the balance of sodium, potassium, and calcium ions.
4. Regulation of Blood Pressure – The kidney releases renin, which controls blood pressure.
5. Hormone Secretion – Produces erythropoietin, which stimulates red blood cell production.