Urinary System Overview and Components

Urinary System Overview

• The urinary system's main function is to filter blood and remove metabolic wastes.
• It consists of the kidneys, ureters, urinary bladder, and urethra.
• Kidneys are located in the posterior abdominal wall, on either side of the vertebral column.
• The right kidney is positioned at the level of T12 to L3, while the left kidney is at the level of T11 to L2.
• The left kidney is higher than the right kidney.
• In females, the ovaries are located near the kidneys.

Urinary System Components

• Kidneys: Filter blood and form urine.
• Ureters: Tubes that carry urine from the kidneys to the bladder.
• Urinary Bladder: Stores urine before elimination.
• Urethra: Tube that carries urine out of the body.

Structures within the Kidney

• Renal pelvis: Cup-shaped structure that collects urine from the calyces.
• Calyces: Collecting tubules that drain urine from the pyramids.
• Renal pyramids: Cone-shaped tissue within the medulla of the kidney.
• Medulla: Inner part of the kidney containing the renal pyramids.
• Cortex: Outer layer of the kidney, containing blood vessels, nephrons, and glomeruli.
• Nephron: Tiny filtering units of the kidney.
• Glomerulus: A cluster of capillaries inside the Bowman's capsule.

Blood Vessels of the Kidney

• Renal artery: Supplies blood to the kidney.
• Renal vein: Carries filtered blood away from the kidney.
• Afferent arterioles: Deliver blood to the glomerulus.
• Efferent arterioles: Carry blood away from the glomerulus.
• Glomerular capillaries: Tiny blood vessels within the glomerulus.

Urine Formation Stages

• Filtration: Passage of plasma fluid from the glomerulus into the glomerular capsule.
• Reabsorption: Recovery of essential substances (water, glucose) and electrolytes back to the bloodstream.
• Excretion: Metabolic waste products (from the blood) are discharged into the urine.

Bladder

• The bladder is a urinary reservoir.
• It has a capacity of 220-500 ml.
• Located posterior to the pelvic symphysis pubis, more anterior to the uteruses in females and to the rectum in males.
• Can hold urine until elimination.

Ureters and Urethra

• Ureters carry urine from the kidneys to the bladder.
• The urethra exists in different lengths in males and females.

Nephron Structure

• Nephrons are the functional units of the kidneys.
• Each kidney contains millions of nephrons.
• Nephrons consist of Bowman's capsule, glomerulus, proximal convoluted tubule, loop of Henle, and distal convoluted tubule.

Explore the intricacies of the urinary system with this quiz, covering key functions, components, and structures of the kidneys, ureters, bladder, and urethra. Test your understanding of how these elements work together to filter blood and eliminate waste.