The kidney

• Kidney


  Two bean-shaped organs in the renal system that help the body pass waste as urine and filter blood before sending it back to the heart
• Components of the kidney

  • Cortex
  • Medulla
  • Renal artery
  • Renal vein
  • Calyx
  • Bladder
  • Urethra
  • Ureters
• Cortex


  • The outer part of the kidney, contains the glomerulus and convoluted tubules, houses and protects the inner structures
• Medulla


  • The smooth, inner tissue of the kidney, contains thousands of nephrons
• How the kidneys work

  1. Blood enters kidneys via renal arteries

  2. Nephrons filter the blood

  3. Needed substances reabsorbed, waste and excess fluid removed as urine

  4. Clean blood returns to body via renal veins

  5. Urine carried to bladder via ureters

  6. Bladder stores urine until released through urethra
• Nephron


  • The filtering unit of the kidney, includes a glomerulus filter and a tubule
• Each kidney has about a million nephrons
• The kidneys perform many crucial functions, including maintaining overall fluid balance, regulating and filtering minerals from blood, filtering waste materials, and creating hormones
• Dialysis patients need to restrict their fluid intake
• Symptoms of later stage chronic kidney disease

  • Weight loss and poor appetite
  • Swollen ankles, feet or hands
  • Shortness of breath and tiredness
  • Blood in urine
  • Increased need to urinate, especially at night
  • Difficulty sleeping
  • Itchy skin and muscle cramps
  • Feeling sick
  • Headaches
  • Erectile dysfunction in men
• Diagnosis methods for kidney disease

  • Blood test measuring creatinine levels
  • Urine test checking albumin and creatinine levels
  • Ultrasound, MRI or CT scan
  • Kidney biopsy
• Treatments for kidney disease

  • Lifestyle changes
  • Medication
  • Dialysis
  • Kidney transplant
• Lifestyle changes for kidney health include stopping smoking, healthy diet, restricting salt intake, regular exercise, reducing alcohol and maintaining a healthy weight
• The textbook pages 80-81 cover the removal of urea, ultrafiltration, reabsorption, osmoregulation, and regulation of water level
• The endocrine system has components that need to be described and their functions explained