Structure of Nephron

Overview of Nephrons

• Each kidney contains approximately one million functional units called nephrons.
• Nephrons are primarily responsible for the filtration of blood.

Nephron Types

• Juxta medullary nephrons: Have a longer loop of Henle, extending deep into the medulla.
• Cortical nephrons: Have a shorter loop of Henle, limited to the cortex region.

Structure of a Juxta Medullary Nephron

• Composed of a renal corpuscle and a renal tubule.

Renal Corpuscle

• Comprised of a dense cluster of blood capillaries known as the glomerulus.
• The glomerulus is surrounded by a thin-walled covering called Bowman's capsule, collectively termed the Malpighian body.
• The glomerulus is a ball-like structure originating from the afferent arteriole.
• High blood volume and pressure enable efficient ultra-filtration in this area.
• Glomerular capillaries feature pores approximately 70 nm in diameter, preventing large molecules and blood cells from entering the tubule.

Renal Tubule

• Begins at Bowman's capsule and consists of various segments:
  • Proximal convoluted tubule (PCT): Highly convoluted, absorbs glucose, amino acids, and other nutrients from the filtrate.
  • Descending limb: Descends toward Bowman's capsule and merges into the common duct known as the collecting duct.
  • Ascending limb.
  • Distal convoluted tubule (DCT).

Collecting Duct

• Functions as a common duct for multiple nephrons, directing urine towards the hilum.
• Urine is collected by the pelvis and ureter for removal from the body.

Blood Supply to Nephron

• The renal artery supplies blood to the nephron, forming smaller arterioles.
• The afferent arteriole gives rise to the densely packed efferent arteriole.