Internal Structure of the Kidney
The kidney has three major parts:
1. Renal Cortex
The outer layer of the kidney where filtration begins.
2. Renal Medulla
The inner part containing pyramid-shaped structures that help concentrate urine.
3. Renal Pelvis
A funnel-shaped area that collects urine and sends it to the ureter.
Urine formed in the kidneys travels through the ureters into the urinary bladder, where it is stored before passing out through the urethra.
What Is a Nephron?
The nephron is the basic structural and functional unit of the kidney.
Each nephron filters blood and forms urine.
A nephron consists of:
Glomerulus
Bowman’s capsule
Tubules
Loop of Henle
Collecting duct
Number of Nephrons
Each kidney contains approximately 8 lakh to 12 lakh nephrons
Together, both kidneys contain nearly 2 million nephrons
The number of nephrons decreases gradually with aging and certain diseases like diabetes and hypertension.
