kidney

• What is the term for the control of body temperature?

  Thermoregulation
• Why is it important to maintain core body temperature?

  To enable enzymes to work at their optimum temperature
• What happens during vasoconstriction?

  Blood vessels supplying the skin constrict
• What is the effect of sweating on body temperature?

  Heat is lost as sweat evaporates
• What occurs during shivering?

  Fast skeletal muscle contractions generate heat
• What is vasodilation?

  Blood vessels supplying the skin dilate
• Where is the thermoregulatory centre located?

  In the brain
• What is the role of the kidneys in maintaining water balance?

  They produce urine by filtering blood

  
• What happens to excess water, ions, and urea in the body?

  They are removed via the kidneys in urine
• What is deamination?

  The process of converting amino acids to ammonia
• Why is ammonia converted to urea?

  Because ammonia is toxic
• What does ADH do in the kidneys?

  It increases water reabsorption in kidney tubules

  
• How does the body control water levels?

  Through the hormone ADH released by the pituitary gland

  
• What is a common treatment for kidney failure?

  Organ transplant or kidney dialysis
• What is the main problem with transplant surgery?

  Rejection of the donated kidney
• Why does the body reject a donated kidney?

  The immune system identifies foreign antigens
• What is tissue typing?

  Finding a close genetic match for transplant
• What are immunosuppressant drugs used for?

  To weaken the immune system and prevent rejection
• What is a disadvantage of dialysis treatment?

  Inconvenience of sessions several times per week
• Why can't protein molecules move from blood to dialysis fluid?

  They are too large to fit through the membrane
• What is diffusion in the context of dialysis?

  Movement of urea from blood to dialysis fluid
• How is the volume of water in urine controlled?

  By the hormone ADH from the pituitary gland

  
• What processes occur in the kidneys to produce urine?

  • Filtration: Small molecules filtered from blood
  • Selective reabsorption: Glucose, some ions, and water reabsorbed
• What are the effects of osmotic changes in body fluids on cells?

  • Cells may lose or gain too much water
  • Inefficient cell function occurs with extreme changes
• What are the disadvantages of kidney transplant surgery?

  • Risk of rejection
  • Lack of donors
  • Risk of infection during surgery
• What are the basic principles of dialysis?

  • Blood is filtered through a dialysis machine
  • Dialysis fluid contains nutrients and no urea
  • Diffusion moves waste from blood to fluid