Urinary System

Overview

The urinary system maintains internal homeostasis through filtration of blood, regulation of fluid balance, and control of electrolyte and acid–base status. By adjusting urine composition and volume, the kidneys play a central role in long-term regulation of blood pressure and plasma osmolality. Urinary physiology integrates glomerular filtration, tubular reabsorption, secretion, and coordinated bladder function.

Key Topics

This section explores nephron physiology, including the proximal and distal tubules and collecting duct, alongside mechanisms of water handling and solute transport. It also examines urinary regulation of acid–base balance and the neural control of micturition. Together, these topics explain how renal processes maintain stable internal conditions despite changing physiological demands.

Clinical Relevance and Learning Focus

Disruption of renal filtration, tubular transport, or bladder control can lead to fluid imbalance, electrolyte disturbance, and acid–base disorders. Understanding urinary physiology supports interpretation of renal function tests, urinary findings, and patterns of lower urinary tract dysfunction. This section emphasises regulatory integration, helping learners connect nephron-level processes with systemic homeostasis and clinical presentation.