Excretion

• Kidney


  Two bean-shaped organs located on the left and right sides of the abdomen
• Kidney


  • About 11 centimeters or 4.3 inches long in adults
  • Receive blood from the paired renal arteries
  • Blood is filtered and wastes are removed alongside salt, sugar and minerals are adjusted
  • Filtered blood is returned to the body and the waste is converted into urine
  • Each kidney is connected to a ureter, a tube that transports the urine into the bladder
• Kidney diseases often affect both kidneys
• If the kidneys' ability to filter blood is hindered, waste and excess fluids build up in the body resulting in abnormalities which do not give symptoms until late in the course of the disease
• Common kidney diseases


  • High blood pressure
  • Blood or protein in the urine
  • Diabetes
  • Kidney stone
  • Urinal tract infection
  • Glomerulonephritis
• Anatomy of the kidney

  • Three external layers: renal capsule, renal fascial, and adipose capsule
  • Adrenal gland found sitting on top of each kidney
  • Right kidney slightly lower than the left kidney, left kidney more centralized than the right
  • Renal veins take blood to the vena cava, renal artery supplies blood to the kidney
  • Renal hilum is the point of entrance and exit of the veins, arteries and nerves that supply the kidney
• Internal layers of the kidney

  • Renal cortex
  • Renal medulla
  • Renal pelvis
• Renal cortex


  Layer of tissue covered by the renal capsule and the renal fascia, provides a space for the hormones from the renal artery and vein to diffuse, produces a hormone necessary for the synthesis of new red blood cells
• Renal medulla


  Inner region of the kidney, contains the renal pyramids
• Renal pelvis


  Contains the hilum, serves as an exit and entrance point for nerves and blood vessels, and as a point of exit to the uterus
• Functions of the kidney

  • Blood pressure regulation
  • Removal of toxins and drugs
  • Excretion of metabolic waste
  • Regulation of osmotic pressure in the body
  • Balances the body fluids
  • Controls the production of red blood cell
  • Produces vitamin D which promotes strong and healthy bones