Nephron Structure and Function

Nephron Structure and Function

• Glomerulus: Acts as an ultrafilter, filtering non-colloidal parts of plasma (glomerular filtrate).
• Bowman's Capsule: Collects the glomerular filtrate.
• Renal Tubule: Starts at Bowman's capsule, ends at collecting tubules, differentiated into four regions:
  • Proximal Convoluted Tubule: First part, highly coiled, prominent brush border for reabsorption.
  • Henle's Loop (Loop of Henle): U-shaped loop in the medulla, four segments (descending thick, descending thin, ascending thin, ascending thick).
  • Distal Convoluted Tubule: Third coiled part, opens into collecting tubules, cubical epithelial cells with granular cytoplasm.
  • Collecting Tubule: Joins distal convoluted tubules of multiple nephrons; forms the duct of Bellini, cubical epithelial cells.
• Afferent/Efferent Arterioles: The arrangement creates higher glomerular pressure, facilitating filtration.

Nephron Functions

• Glomerulus: Filters the non-colloidal parts of blood plasma.
• Proximal Convoluted Tubule: Reabsorbs glucose, amino acids, water, NaCl, phosphate, and sulphate.
• Henle's Loop: Reabsorbs the rest of glucose and bicarbonate, water reabsorption also occurs.
• Distal Convoluted Tubule: Reabsorbs water under influence of ADH and aldosterone, synthesizes ammonia, and hydrogen ions.
• Collecting Tubule: Reabsorbs water and concentrates urine; collects urine, sends it to the duct of Bellini.

Role of Nephron in Urine Formation

• Filtration: Glomerulus filters blood, producing glomerular filtrate.