Homeostasis in action -B12

• What happens to enzymes when body temp is too high, why is this bad ?

  They denature

  enzymes are needed for metabolic processes
• What happens to enzymes is body temp is too low , why is this bad ?

  • enzymes rate decreases
  • affects metabolism
• How is body temp lowered if too high?

  detected by thermoreceptors

  cooling mechanisms -sweating and vasodilation
• how is body temp raised if to low ?

  Detected by thermoreceptors

  heating Mechanisms - shivering and vasoconstriction
• What affect does ADH have on the kidney collecting ducts?

  increases permeability to water
• where does deamination occur?

  Liver and kidneys
• what affect does alcohol have on ADH?

  Inhibits ADH
• what is released when you are dehydrated ?

  more ADH
• What should be in urine ?

  Urea, water, salts, and other waste products.
• What shouldn’t be in urine ?

  glucose ,protein,cells
• How does the kidney work ?

  protein and cells are filtered out during ultrafiltration in the glomerulus

  glucose is selectively re absorbed in the proximal convoluted tubule

  sodium ions diffuse out in the loop of Hemel through active transport
• What is in dialysis fluid ?

  no salt or urea

  sugar and mineral concentration are same as the blood
• Which direction does dialysis fluid flow in ?

  opposite direction to the blood
• How does excess salt move out of the blood during dialysis ?

  Diffusion along an concentration gradient
• How does urea exit the blood during dialysis ?

  Diffusion along a concentration gradient
• What are the risks of kidney transplants ?

  Rejection, infection
• What are the advantages of kidney transplants ?

  Improved quality of life
• Why is carbon dioxide removed from the body?

  if it dissolves it produces carbonic acid which affects enzyme function

  it diffuses out of cells into blood down a concentration gradient
• Why is urea removed from the body ?

  produced when excess protein is broken down

  urea is toxic if it builds up in the blood