Maintaining the Body's Water Balance (T)

• What hormone is used to control the water level in the blood?

  ADH
• What should higher-tier students be able to describe by the end of the video?

  How ADH controls water levels, how kidney dialysis works, and evaluate kidney transplants and dialysis.
• How do the kidneys adjust the levels of ions and water in the blood?

  • Filter out water, urea, and ions from the blood
  • Selectively reabsorb some water and ions back into the blood
• What happens to the body when a person exercises on a hot day?

  The body loses water through sweating.
• What triggers the release of ADH from the pituitary gland?

  When the blood becomes too concentrated.
• What effect does ADH have on the kidney tubules?

  It makes kidney tubules more permeable to water.
• What happens to urine production when ADH is released?

  Less urine is produced.
• What is the role of the pituitary gland when blood water levels return to normal?

  It stops releasing ADH.
• What occurs when a person drinks a large amount of water?

  • The concentration of water in the blood rises
  • The pituitary gland stops releasing ADH
  • Kidneys reabsorb less water
  • More urine is produced
• What is kidney dialysis used for?

  To adjust levels of water, ions, and urea in patients with kidney failure.
• How does kidney dialysis work?

  Blood passes over a semipermeable membrane to remove waste products.
• What is the function of the dialysis fluid in kidney dialysis?

  It creates a concentration gradient for urea to diffuse out of the blood.
• What are the advantages and disadvantages of kidney dialysis?

  Advantages:

  • No shortage of dialysis machines
  • Can be performed regularly

  
  

  Disadvantages:

  • Inconvenient with frequent hospital visits
  • Requires a controlled diet
  • Expensive long-term treatment
• What is a kidney transplant?

  Replacing a diseased kidney with a healthy one from a donor.
• What is a potential issue with kidney transplants?

  The donated kidney may be rejected by the immune system.
• Compare the advantages and disadvantages of kidney transplants and dialysis.

  Advantages of transplants:

  • Patients can lead a normal life
  • Only expensive initially

  
  

  Disadvantages of transplants:

  • Shortage of donors
  • Need for lifelong anti-rejection drugs

  
  

  Advantages of dialysis:

  • No shortage of machines

  
  

  Disadvantages of dialysis:

  • Frequent treatments required
  • Controlled diet necessary
  • Expensive long-term