JoVE Logo

Sign In

Chapter 29

The Urinary System

Introduction to Urinary System
Introduction to Urinary System
The urinary system consists of two kidneys, two ureters, the urinary bladder, and the urethra. The kidneys are bean-shaped organs located in the ...
External Anatomy of the Kidney
External Anatomy of the Kidney
The kidneys are a pair of bean-shaped organs in the human body that play a critical role in maintaining overall health. They filter out waste products ...
Internal Anatomy of the Kidney
Internal Anatomy of the Kidney
The kidneys are essential organs in the human body, performing a myriad of tasks that maintain homeostasis and overall health. Anatomical Position and ...
Blood and Nerve Supply to the Kidney
Blood and Nerve Supply to the Kidney
The segmental arteries branch out, supplying different kidney regions. These segmental arteries branch off and pass through the renal columns as ...
Nephrons
Nephrons
A nephron is the functional unit of the kidney. It comprises two main parts — the renal corpuscle and renal tubule. The renal corpuscle, where blood ...
Renal Corpuscle
Renal Corpuscle
The glomerulus and Bowman's capsule are two essential components of the nephron, which is the functional unit of the kidney. These microscopic ...
Renal Tubule and Collecting Duct
Renal Tubule and Collecting Duct
The nephron measures approximately 3 cm and consists of the proximal convoluted tubule, loop of Henle, and distal convoluted tubule. The proximal ...
Physiology of Urine Formation
Physiology of Urine Formation
The formation of urine involves three steps —  glomerular filtration, tubular reabsorption, and tubular secretion. Glomerular filtration occurs ...
Glomerular Filtration
Glomerular Filtration
During glomerular filtration, blood plasma is pushed through the pores of a filtration membrane. The glomerular capillaries and podocytes together form ...
Glomerular Filtration: Net Filtration Pressure
Glomerular Filtration: Net Filtration Pressure
Glomerular filtration, a key process in the kidneys, is regulated by three main pressures: Glomerular blood hydrostatic pressure (GBHP), Capsular ...
Glomerular Filtration Rate and its Regulation
Glomerular Filtration Rate and its Regulation
The glomerular filtration rate or GFR is the volume of filtrate formed per minute by the glomeruli. Any changes in the local blood pressure and flow can ...
Tubular Reabsorption and Secretion
Tubular Reabsorption and Secretion
Tubular secretion and reabsorption are two critical processes in the nephron tubule of the kidneys. When the fluid filtered from the glomerulus enters the ...
Reabsorption and Secretion in the PCT
Reabsorption and Secretion in the PCT
The proximal convoluted tubules, or PCTs, reabsorb most filtered water, ions, glucose, and amino acids. Sodium ion transport is a critical process in the ...
Reabsorption and Secretion in the Loop of Henle
Reabsorption and Secretion in the Loop of Henle
The thick ascending limb of the nephron loop has Na+–K+–2Cl− symporters in the apical membranes of its cells. These symporters ...
Reabsorption and Secretion in the DCT and Collecting Duct
Reabsorption and Secretion in the DCT and Collecting Duct
The early part of the distal convoluted tube, or DCT, reabsorbs around 10 to 15% of the filtered water and 5% of the filtered sodium and chloride ions. ...
Urine: Physical and Chemical Properties
Urine: Physical and Chemical Properties
Urine is mostly water, which makes up around 95% of its volume. The remaining 5% consists of different solutes. Urea, a byproduct of amino acid breakdown, ...
Formation of Dilute Urine
Formation of Dilute Urine
The kidney's juxtamedullary nephrons produce dilute urine when the fluid intake is high. In the renal cortex, the osmolarity of the interstitial fluid ...
Formation of Concentrated Urine
Formation of Concentrated Urine
There is a medullary osmotic gradient of solutes in the interstitial fluid from the renal cortex through the medulla. This gradient is established and ...
Renal Clearance
Renal Clearance
The glomerular filtration rate is an effective metric for assessing kidney function. One way of measuring GFR is by calculating renal clearance. Renal ...
Ureters
Ureters
Ureters are retroperitoneal tubes on either side of the vertebral column that transport urine from each kidney to the urinary bladder. They have thick ...
Urinary Bladder
Urinary Bladder
The urinary bladder is a hollow, muscular sac that temporarily stores about 600 mL of urine before micturition.  It is retroperitoneally situated on ...
The Micturition Reflex
The Micturition Reflex
Micturition or urination primarily involves coordination between the bladder detrusor muscle and two sphincters to control bladder emptying. It is ...
Urethra
Urethra
The urethra is a tube-like structure extending from the lower end of the urinary bladder to the external opening for releasing urine out of the body. In ...
Dialysis
Dialysis
Renal failure is classified as acute when the glomerular filtration rate or GFR suddenly drops below 15 mL/min or ceases entirely. In contrast, a gradual ...
Disorders of the Urinary System
Disorders of the Urinary System
Urinary system disorders can arise from infections, stress, age, congenital abnormalities, and lifestyle. Urinary tract infections are typically caused by ...
JoVE Logo

Privacy

Terms of Use

Policies

Research

Education

ABOUT JoVE

Copyright © 2025 MyJoVE Corporation. All rights reserved