Unit 3 Flashcards
What does the body need to get supplies to the cells and remove the waste material they produce?
A transport system which is the function of the blood circulation system.
What are the three components of your blood circulation system?
Blood vessels (pipes), the heart (pump) and the liquid (the blood).
How many circulation systems does your body have?
2
What does your first circulation system do?
Carry blood to your lungs and back.
What does your second circulation do?
Carries around your blood around the rest of your body and back again to the heart.
Why is the blood circulation system very efficient?
Fully oxygenated blood returns to heart from lungs. Blood can then be sent off to different parts of the body at high pressure so more areas of your body can receive oxygenated blood very quickly.
In your circulatory system, what carries blood away from your heart to the organs of your body?
The arteries.
In your circulatory system, how does blood return to your heart from the organs of your body?
By the veins.
What are the walls of your heart made up of?
Muscle.
How is the heart supplied with oxygen?
By coronary arteries.
How many sides does the human heart have?
2, which fill and empty at the same time.
Where is the atria?
The top chambers of your heart where blood first enters.
What does the vena cava do?
Brings deoxygenated blood from your body into the right atrium.
What does the pulmonary vein do?
Brings oxygenated blood from your lungs into your left atrium.
How is blood forced down onto the ventricles?
By the atria contracting.
What do ventricles do?
Pump blood out of the heart.
How is deoxygenated blood forced out of the heart?
Right ventricle forces the blood to the lungs in the pulmonary artery.
How is oxygenated blood taken away from the heart?
Left ventricle pumps the blood around the body via the aorta (big artery).
What does the kidneys do?
Get rid of toxic waste such as urea and adjust the amount of the dissolved ions and water in the blood.
What are the filtration units in the kidneys called?
Nephrons.
What is the first step in filtration using the kidneys?
High pressure is built up which squeezes water, urea, ions and sugar out of the blood and into the Bowman’s capsule. Membranes between blood vessels and the Bowman’s capsule act like filters so big molecules are not squeezed out like protein and blood cells which stay in the blood.
What is the second step in filtration using kidneys?
Liquid flows along nephron and useful substances are reabsorped back into the blood.
What is absorbed back into the blood after ultrafiltration?
All sugar via active transport.
Sufficient ions via active transport.
Sufficient water.
What is the third step in filtration using the kidneys?
Remaining substances such as urea travel out of the nephron into ureter and down to bladder as urine.
What does it mean to have kidney failure?
Kidneys don’t remove waste substances from the blood.
What happens if your kidneys do not work properly?
Waste substances build up in the blood and you lose your ability to control the levels of ions and water in your blood.
What are the treatment options for those with kidney failure?
Kept alive by dialysis or they can have a kidney transplant.
Why does dialysis have to be done regularly?
To keep the concentration of dissolved substances in the blood at normal levels and remove waste substances.
What happens in a dialysis machine?
The persons blood flows alongside a selectively permeable barrier surrounded by dialysis fluid.
What is the selectively permeable barrier permeable to in a dialysis machine?
Ions and waste substances but not to large molecules like proteins or blood cells- just like membranes in kidney.
What does the dialysis fluid have the same concentration as?
Dissolved ions and glucose as healthy blood.
Why is it important the dialysis fluid has the same concentration of dissolved ions and glucose as healthy blood?
It means useful dissolved ions and glucose won’t be lost from blood firing dialysis.
What is the only thing that can diffuse across the semi permeable barrier in a dialysis machine?
Waste substances such as urea and excess ions and water.
How often does dialysis need to be done?
Three times a week, 3-4 hours.
What may dialysis cause?
Blood clots or infections.
What is the only cure for kidney disease?
Kidney transplant.
Who are healthy kidneys normally transplanted from?
People who have died suddenly such as in a car accident, are on the organ donor register or carry a donor card.
How else can we get a kidney transplant if not from people who have died?
By those who are alive as we have 2.
What are the problems of kidney transplants?
Donor kidney can be rejected by the patients immune system, foreign antigens on the kidney are attacked by the patients antibodies.
How can rejection of a kidney be prevented?
Donor with tissue type that closely matches the patient is chosen or the patient is treated with drugs that suppress the immune system so their immune system won’t attack the kidney.
What is tissue type based on?
Antigens which are proteins on the surface of most cells.
What are the disadvantages of dialysis?
Kidney dialysis machines are expensive.
Not a pleasant experience.
What are the advantages of dialysis?
Keep you alive while waiting for a transplant.
What are the advantages of kidney transplants?
Cheaper can put an end to hours spent on dialysis machines.
What are the disadvantages of kidney transplants?
Long waiting lists.
Person is more vulnerable to illness from immunosuppressant drugs.
Chance it will be rejected.
What is the kidneys role in homeostasis?
Adjustment of water content.
What are three ways water is lost from the body?
Urine, sweat and air we breathe out.
How does the body balance water?
Liquids consumed between the amount sweated out and the amount excreted by our kidneys in urine.
What does the kidneys have to constantly balance?
Water coming in against water going out.
