Flashcards in Homeostasis Deck (22):
What are the 2 main waste products that have to be removed from the body?
1. Carbon dioxide, produced by respiration and removed via the lungs when we breathe out.
2. Urea, produced in the liver by the breakdown of amino acids and removed by the kidneys in the urine, which is temporarily stored in the bladder.
What is the effect of having the wrong water or ion content in the body?
Too much water may move into or out of the cells and damage them.
How do water and ions enter the body?
When we eat and drink.
What are 2 method of treating someone with kidney failure?
1. A kidney dialysis machine
2. Having a healthy kidney transplanted
What does the treatment of dialysis do?
Treatment by dialysis restores the concentrations of dissolved substances in the blood to normal levels and has to be carried out at regular intervals.
What might happen after a kidney transplant unless precautions are taken?
The donor kidney may be rejected by the immune system.
What are antigens?
Antigens are proteins on the surface of cells.
If the recipients antibodies don't recognise the antigens on the donors organs, what will happen?
The recipients antibodies will attack the antigens.
What 2 precautions are made to prevent rejection of the transplanted kidney?
1. A donor kidney with a 'tissue-type' similar to that of the recipient is used.
2. The recipient is treated with drugs that suppress the immune system.
What is the purpose of sweating?
Sweating helps to cool the body.
What is the purpose of the thermoregulatory centre in the brain?
To monitor and control body temperature.
How is the thermoregulatory centre in the brain adapted to monitor and control body temperature?
It has receptors sensitive to the temperature of the blood flowing through the brain.
How is skin temperature monitored?
Temperature receptions in the skin send impulses to the thermoregulatory centre, giving information about skin temperature.
If the core body temperature is too high what happens to blood vessels?
Blood vessels supplying the skin capillaries dilate so that more blood flows through the capillaries and more heat is lost.
If the core body temperature is too high what happens to sweat glands?
Sweat glands release more sweat which cools the body as it evaporates.
If the core body temperature is too low what happens to blood vessels?
Blood vessels supplying the skin capillaries construct to reduce the flow of blood through the capillaries.
If the core body temperature is too low what happens to muscles?
Muscles may 'shiver' - their contraction needs respiration, which releases some energy to warm the body.
What is controlled and monitored by the pancreas?
The blood glucose concentration
HOW does the pancreas monitor and control the blood glucose concentration of the body?
The pancreas produces the hormone insulin, which allows the glucose to move from the blood into the cells.
What happens when blood glucose levels fall?
A second hormone, glucagon, is produced in the pancreas. This causes glycogen to be converted into glucose and be released into the blood.
What is type 1 diabetes?
Type 1 diabetes is a disease in which a person's blood glucose concentration may rise to a high level because the pancreas does not produce enough of the hormone insulin.