B3.3 Flashcards
Why do humans need to remove waste products from their bodies
To keep their internal environment relatively constant
Why might people whose kidneys do not function properly may die
Because toxic substances accumulate in their blood
How can someone with kidney failure’s life be saved
By using dialysis machines or having a healthy kidney transplanted
What 4 things need to be kept at very narrow ranges
Water content
Ion content
Temperature
Blood glucose levels
What are 2 waste products from the body
Carbon dioxide
Urea
How is the waste product carbon dioxide made in the body and how it is removed
Produced by respiration and removed via the lungs when we breathe out
How is the waste product urea produced and how is it removed
Produced by the liver by tge breakdown of amino acids and removed by the kidneys in the urine and temporarily stored in the bladder
What happens if the water or ion content of the body is wrong
Too much may move into or out of the cells and damage them
How do water and ion enter the body
When we eat or drink
What is the process of a healthy kidney producing urine
First filters the blood
Reabsorbing all the sugar
Reabsorbing the dissolved ions needed by the body
Reabsorbing as much water as the body needs
Releasing urea, excess ions and water as urine
What does treatment by dialysis do
Restores the concentrations of dissolved substances in the blood to normal levels
When does the treatment by dialysis needed to carried out
At regular intervals
What happens in a dialysis machine
A persons blood flows between partially permeable membranes
What has the same concentration as the dialysis fluid
Useful substances such as blood
Why does the dialysis machine have to have the same concentration as the blood
So that glucose and useful mineral ions are not lost
What passes out from the blood into dialysis fluid
Urea
What happens in kidney transplants
A diseased kidney is replaced with a healthy one from a donor
When having a kidney transplant why do precautions need to be taken
Because the donor kidney may be rejected by the immune system
What are antigens
Proteins on the surface of cells
Why might the recipients antibodies attack the antigens on the donor organ
Because they do not recognise them as part of the recipients body
What must happen to prevent rejection of a transplanted kidney
A donor kidney with a ‘tissue type’ similar to that of the recipient used
The recipient is treated with drugs that suppress the immune system
What does sweating do
To cool down the body
What happens when it is hot
Water is lost
What needs to happen if u lose more water
More water has to be taken as drink or in food to balance this loss.
What controls and monitors body temperature
The thermoregulatory centre int the brain
What does tge thermoregulatory centre have
Receptors sensitive to the temperature of the blood flowing through the brain
What do temperature receptors in the skin send to the thermoregulatory centre
Impulses which gives information about skin temperature
What 2 things happen if the core body temperature is too high
Blood vessels supplying the skin capillaries dilate so that more blood flows through the capillaries and more heat is lost
Sweat glands release more sweat which cools the body as it evaporates
What 2 things happen if the core body temperature is too low
Blood vessels supplying the skin capillaries constrict to reduce the flow of blood through the capillaries
Muscles may shiver- their contraction needs respiration, which releases some energy to warm the body
What does the pancreas do
Controls and monitors the blood glucose concentration of the body
What 2 things does the pancreas produce and what do they allow
Produces hormone insulin which allows the glucose to move from the blood into the cells
Produces hormone glucagon when the blood glucose levels fall and causes glycogen to be converted into glucose and to be released into the blood
What is type 1 diabetes
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
How can type 1 diabetes be controlled
By careful attention to:
diet
Exercise
Injecting insulin
