Homeostasis Flashcards
What do humans need to control by homeostasis? (3 marks)
Water and ions Body temperature Blood glucose
What is homeostasis?
Maintaining a constant internal environment
What waste products do humans need to remove?
CO 2 and urea
What is urea?
Broken down amino acids
Where is urea made?
In the liver
Where does urea get removed?
In the kidney
Why is concentrated urine darker in colour?
It contains less water
What are the filtration units of the kidney?
Nephrons
What are the 3 main steps of urine production?
Ultrafiltration Selective reabsorption Release of waste products
Should a healthy person have have protein in their urine? Why?
No, proteins are too big to pass through into the filtrate as are blood cells
Should a heathy person have glucose in their urine? Why?
No, all of it is reabsorbed by active transport
What are the options for a person with kidney failure?
Dialysis Transplant
What are the cons of Dialysis? (3 marks)
Have to have it 3 times a week for 4 hours Can lead to infections/ blood clots Have to watch diet Have to watch liquid intake Costly
What are the problems with transplanted kidneys? (3 marks)
Shortage of donors May reject kidney Have to take immuno- suppressant drugs Major operation so can be risky
Where is the thermoregulatory centre?
Hypothalamus in the brain
Where does information on body temperature come from?
Receptors in the brain detect blood temperature Receptors in the skin send information about temperature
If you are too hot, what happens to cool you down?
Sweat Vasodilation Hairs lie flat
If you are cold what does your body do?
Hairs stand up No sweat is produced Vasoconstriction Shivering
When is insulin produced?
When blood glucose is too high
Where does insulin come from?
The pancreas
What are the target organs for insulin?
Liver and muscles
What is excess glucose turned into?
Glycogen
What does a Type 1 diabetic do to control blood glucose? (3 marks)
Controls diet Injects insulin at mealtimes Takes regular exercise
Which hormone is produced when glucose is low?
Glucagon (when the glucose has gone) :-)
What is this?
Vasodilation - make sure you can explain it :)
What is this?
Vasoconstriction - make sure you can explain it! :)
What is this and what does it do?
It is a pancreas, it produces the hormones insulin and glucagon and the enzymes carbohydrase, protease and lipase! Wow!! It’s a busy organ!!
