The Urinary System

Structure of the Urinary System

• The main organs of the urinary system are the kidneys.
• The kidneys filter the blood and send unwanted material to the bladder for storage until they leave the body.

Key Components of the Urinary System

• The urinary system consists of:
  1. Kidneys (2)
  2. Ureters (2)
  3. Bladder
  4. Urethra
• Kidneys:
  • The kidneys are bean-shaped, fist-sized organs found in the small of the back, below the diaphragm.'
  • Function: Filter the blood to remove urea, salt, and water, which are then sent to the bladder.
• Ureters: Tubes that carry urine from each kidney to the bladder.
• Bladder: Stores urine until it is ready to leave the body.
• Urethra: A single tube that carries urine from the bladder out of the body.

Urea Formation

• Urea is formed in the liver through the breakdown of excess amino acids in a process called deamination.
• Urea, excess salt and water travel through the blood to the kidneys for excretion.
• This is sent to the bladder for storage and released through the urethra and out of the body

Renal artery	Supply blood to the kidneys.
Renal vein	Carries blood from the kidney to the heart.
Ureters	Connect the kidneys to the bladder, transporting urine.
Bladder	A muscular, elastic organ that stores urine until urination.
Urethra	A tube that carries urine from the bladder out of the body during urination.
Sphincter muscle	Found at the top of the urethra. It stays contracted until urination. When it relaxes, urination occurs.