Maintaining body's water balance

• What hormone controls the water level in the blood?

  ADH
• What is the role of ADH in the kidneys?

  It makes kidney tubules more permeable to water
• What happens when blood becomes too concentrated?

  The pituitary gland releases ADH
• How does the release of ADH affect urine production?

  Less urine is produced when ADH is released
• What occurs when the blood water level returns to normal?

  The pituitary gland stops releasing ADH
• What is a negative feedback cycle?

  A process that counteracts changes in the body
• What happens when a person drinks a large amount of water?

  The pituitary gland stops releasing ADH
• How does kidney dialysis work?

  It filters blood through a semipermeable membrane
• What does the dialysis fluid contain?

  Normal concentrations of water and ions
• Why is the dialysis fluid constantly refreshed?

  To maintain a concentration gradient for urea
• What is a disadvantage of kidney dialysis?

  It requires frequent hospital visits
• What is a kidney transplant?

  A procedure to replace a diseased kidney
• What is a potential issue with kidney transplants?

  The donated kidney may be rejected
• What are the advantages and disadvantages of kidney dialysis and kidney transplants?

  Advantages of dialysis:

  • No shortage of machines
  • Immediate treatment available

  
  

  Disadvantages of dialysis:

  • Frequent hospital visits required
  • Controlled diet necessary
  • Long-term expense

  
  

  Advantages of transplants:

  • Patients can lead a normal life
  • Only initial expense

  
  

  Disadvantages of transplants:

  • Shortage of donors
  • Risk of kidney rejection
  • Lifelong anti-rejection medication needed
• What waste product do the kidneys remove from the blood?

  Urea
• What happens to the concentration of water in the blood during sweating?

  The concentration of water decreases
• How do kidneys adjust the levels of ions in the blood?

  By filtering and reabsorbing ions
• What is the effect of ADH on kidney tubules?

  It increases their permeability to water
• What is the main purpose of kidney dialysis?

  To adjust levels of water, ions, and urea
• Why do patients on dialysis need a controlled diet?

  To prevent excessive urea production
• What is the initial cost comparison between dialysis and transplants?

  Dialysis is more expensive long-term
• What is the role of anti-rejection drugs in kidney transplants?

  To prevent the immune system from rejecting the kidney