B3 - Homeostasis Flashcards
(26 cards)
What are the 6 things that need to be controlled?
Body temperature Water content Ion content Blood sugar Carbon dioxide Urea
Why does the body keep body temperature at 37 degrees?
It is the optimum temperature for enzymes
How is the body temperature measured by the brain?
The thermoregulartory centre in the brain has receptors that are sensitive to the temperature of the blood that is passing by it
What 3 things happen when the body is too hot?
Hairs lie flat
Sweat is produced by sweat glands and is evaporated from the skin
Blood vessels dilate so that the blood flows closer to the surface of the skin
What 3 things happen when the body is too cold?
Hairs stand up to form an insulating layer of air
No sweat is produced
Blood vessels constrict so that the blood is further from the surface
What is homeostasis?
The maintenance of a constant internal environment
What 3 things do kidneys do?
Remove urea from the blood
Adjust ions in the blood
Adjust water content in the blood
Describe the journey of urea in the body
It is produced by the liver as a waste product
It is released into the blood by the liver
The kidneys filter it out of the blood and it is stored as urine in the bladder and it is excreted
How do the kidneys adjust the ion content?
Excess ions that would upset the balance of the ions and water are removed by the kidneys and added to the urine to be excreted
What is the other way that ions can be removed from the body?
In sweat
What are the 3 ways that water is lost from the body?
Urine
Sweat
Breathed out air
In which 3 ways is the amount of water regulated?
Liquids consumed
Amount sweated out
Amount excreted by the kidneys into the urine
If someone sweats a lot, how will their urine be different?
Less urine will be produced but it will be more concentrated
This is because there is less water available that can make it more dilute
What are the 3 important substances that sports drinks contain and why?
Water and ions replace those lost in sweat
Sugar can be used in respiration to give the body more energy
What are the 2 hormones that control blood sugar?
Insulin
Glucagon
When is insulin used?
When blood glucose level is too high
Describe the journey of insulin and how it works
It is secreted by the pancreas and travels with the blood until it reaches the liver
It causes the liver to turn glucose into glycogen causing blood sugar to decrease
When is glucagon used?
When the blood glucose level is too low
Describe the journey of glucagon and how it works
It is secreted by the pancreas and travels with the blood to the liver
It makes the liver turn glycogen into glucose meaning that the blood glucose level is increased
What is type 1 diabetes?
A condition where the pancreas produces little or no insulin meaning the blood sugar level is too high
What are the 3 simple ways of controlling type 1 diabetes?
Eating less simple carbohydrates
Regular exercise
Injecting insulin (insulin therapy)
What are the old and new ways of getting insulin for patients?
The old way was to extract it from the pancreases of pigs and cows
The new way is to make human insulin with genetic engineering
Give 2 reasons that the new method of getting insulin is better
Human insulin does not have any side-effects where animal insulin does
No animals are killed in the new method
What is the more difficult way of removing type 1 diabetes?
A kidney transplant
