Section 1 – Blood cells
1. What substances are present in the blood?
nutrients (…), oxygen, carbon dioxide, waste, water, hormones, enzymes, vitamins
2. What kind of blood cells are present in our blood. In what relative numbers (per mm3)?
erythrocytes (red blood cells – 4-6 million / mm3 – carry oxygen and carbon dioxide
thrombocytes (platelets) – 200.000 – 300.000 / mm3 – to make blood clot …
leucocytes (whote blood cells) – 5000 – 7000 / mm3 – to defend the body …
3. Make a table in which you present the cell types and their functions. (see above)
4. Red blood cells have no nucleus. What does that tell you about their lifespan?
they can only live short because a cell needs the nucleus to control the cell
5. Use Figure 5 for this question. Do leukocytes have nuclei?
yes – only red blood cells and platelets have no nucleus
6. Blood is takes of a person who is ill. What do you think will be different in Fig. 6?
the number of leucocytes will increase (fighting the disease)
7. Make a list of the events that take place when a blood vessel is damaged.
a substance is released – fibrin is produced – this web catches platelets and red blood
cells – a plug is formed in the damaged blood vessel
Section 2 – a double circulation
8. A red blood cell present in your left leg has just passed on its oxygen to the muscle
cells and goes to the lungs to collect more oxygen.
How many times does this erythrocyte pass the heart minimally before it returns to the
muscles in your left leg?
It enters your heart coming from the leg (right atrium – ventricle) – then it leaves for
the lungs and re-enters the heart (left atrium-ventricles) to then set off for the leg
again
Section 3 – the heart
9. Study the heart and all its parts carefully. Now close your booklet and make a
schematic drawing of a heart with all the parts and their names in it. Afterwards check
your drawing and correct it. Make sure it is a schematic drawing, a real heart s too
difficult to draw. Don’t forget the attached blood vessels.
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10. What is the advantage of the valves in the heart. What would happen in the circulation
if there were no valves in the heart?
if there were no valves, the blood would flow back every stroke of the heart and the
blood would not move foreward
Section 4 – one contraction of the heart
11. What happens with the volume of a ventricle when it relaxes?
a muscle that relaxes becomes larger – in this case the volume of the ventricle
becomes larger
12. What happens with the pressure in a ventricle when it relaxes?
if the volume increases, the pressure decreases
13. What effect does the relaxation of a ventricle have on what valves?
the decrease in pressure sucks blood into the ventricles from two sides: from the
artery and from the atrium – the valves at the beginning of the artery will close and
the ones between the atrium and the ventricle will open
14. From where to where does the blood flow during the relaxation of a ventricle?
from the atrium towards the ventricle
15. What does the atrium do after the relaxation of the ventricle?
it enters a systole of the atrium – this means that the atrium contracts – squeezing
blood into the ventricle
16. Describe the blood flow following the action of the atrium.
it flows into the ventricle
17. The cycle of a complete heart contraction if completed by the ventricular systole.
What is a ventricular systole?
that is when the ventricle contracts – pushing out the blood into the arteries
18. Describe what happens during a ventricular systole with certain valves and blood flow.
the valves between the atria and ventricles close and the ones between the ventricles
and arteries open to let the blood flow into the arteries
19. Write down exactly (step by step) what happens during one complete cycle of a heart
beat. Use a drawing of the heart.
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Section 5 – names of blood vessels
20. Through which blood vessels and through which parts of the heart does a glucose
molecule (that has just been absorbed into the blood in the intestine) flow when it
travels from the small intestine to muscle cells in the left leg (where it will be respired
to give energy to the muscle there)?
capillaries in the intestine – hepatic portal vein – hepatic vein – inferior vena cava –
right atrium – right ventricle – pulmonary artery – pulmonary capillaries – pulmonary
vein – left atrium – left ventricle – aorta – iliac artery
21. Through which organ(s) does a red blood cell always flow in 1 circulation (rondgang)?
1 – the heart
4 – the head and arms
2 – the lungs
3 – the liver
it always flows through these parts and sometimes through the other ones
Section 6 – functions of the blood vessels
22. Does the hepatic portal vein transport a lot of nutrients:
1 – when someone has just eaten? – yes, because the nutrients have been absorbed
by the intestine – and are passed on to the liver
2 – when someone has not eaten for a long time? – no, because the intestines have
used up the nutrients present in the mesenteric arteries and have not given off any
new nutrients
23. Two situations:
1 – someone is sitting quietly in a chair – this person is not using anything (almost)
so he doesn’t need anything for respiration
2 – someone is working very hard / running very hard – this person has used up a
lot of the glucose in the blood and needs new glucose – this is put in the blood by the
liver – in the hepatic vein
a When does the liver put glucose into the blood (situation 1 or 2)?
not situation 1 because he is digesting the food and absorbing the nutrients into hjs
blood, the liver is only taking nutrients out of the blood for storage – in situation 1 he
is using glucose for respiration; the level of glucose drops and must be restored
(hersteld) by the liver by putting more glucose into the blood
b Explain your answer.
c When the liver puts glucose in the blood; in what blood vessel is the glucose
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concentration highest?:
1 – hepatic vein
2 – hepatic portal vein
3 – inferior vena cava
d Explain your answer.
24. Peter says that an artery always contains a lot of oxygen.
Explain that this is not true / not always.
this goes for all arteries except for one: the pulmonary artery – this one contains very
little oxygen because its job is to collect oxygen at the lungs and is therefore low in
oxygen – the pulmonary vein is high in oxygen
25. How could you describe the function of the liver in your body (one of the functions,
because it has many more)?
to control the level of glucose in the blood – it raises it when it is too low and lowers it
when it is too high
Section 7 – types of blood vessels
26. Blood that flows from the heart to the kidneys and back to the heart again flows
through a number of blood vessels in random order (willekeurige volgorde):
artery, capillary, venule, arteriole and vein.
Place them in the correct following order.
artery – arteriole – capillary – venule – vein
27. a Which of the blood vessels in question 26 is the thinnest. – capillary
b Which of the blood vessels in question 26 contain most oxygen? – artery / arteriole
c In which of the blood vessels in question 26 is the blood pressure highest? – artery
(closest to the heart)
d From which of the blood vessels in question 26 does oxygen diffuse towards the
cells in the tissues and organs? – capillaries
28. How far does an oxygen molecule need to travel maximally from a capillary to reach a
cell? – never more a fraction of a millimetre
29. How can plasma leave the capillary to form interstitial fluid?
A it goes through the cells
B it passes between the cells
C it leaves the capillary at its open end
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30. Where do we find interstitial fluid?
A between the cells
B in the blood vessels
C in the cells
D in the capillaries
31. What is the function of interstitial fluid?
its function is to bring nutrients and oxygen to the cells and to remove waste (CO2)
from the cells – it also helps to keep cells wet / not let them dry out
32. In a well trained muscle as the calf (de kuitspier) of a athlete you will find more
capillaries than in the calf of an untrained individual.
Explain that the well trained muscle needs more capillaries.
when running the athlete needs oxygen and nutrients – the more capillaries, the more
nutrients it can receive – if he wouldn’t have that many capillaries, the athlete would
lack oxygen in his muscles so that his muscle don’t work any more (or start producing
lactic acid (melkzuur))
33. When you are resting after dinner, the precapillary sphincter in arterioles leading to
your intestine relax, whereas the precapillary sphincter in the arterioles leading to your
calf contract.
Explain this step by step for both sphincters.
when you rest your intestine need to work hard – they need to take nutrients out of
the blood – the sphincters need to let more blood go to the intestines
on the other hand do your muscles need less oxygen and therefore less blood so that
these sphincters can contract and let through less blood pass
Veins, valves and muscles
34. What makes the blood flow through the arteries?
the beating of the heart – the blood pressure
35. Explain that this force can not make the blood flow through the veins.
the pressure drops enormously in the capillaries so that it can no longer be pushed
forward by the heart
36. Some veins are located in or between muscles.
What happens to the blood in these veins when the muscles contract?
Explain in at least three steps.
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the veins contain valves – the muscles contract and squeeze the veins – the blood can
only go in one direction because of the valves – this way is up to the heart
37. What happens when the muscles relax again?
Explain in three steps.
the veins becomes large again – the volume increases – the veins sucks in blood –
because of the valves the blood can only come from below – the vein waits for the
next muscle contraction
38. Varicose veins are found in people who have s job that requires standing up all day.
because of that the veins stretch. The valves are no longer able to close.
What is the effect of this on the blood flow through these veins?
since the valves do not make contact anymore, the blood flows back every time the
muscle relaxes and the veins become wide again
Section 8 - Coronary arteries
39. What is the function of the coronary artery?
the coronary artery brings blood with nutrients and oxygen to the muscle cells of the
heart (so they can respire and make the heart contract and pump the blood
throughout the body)
40. From which blood vessel does the coronary artery originate (waaruit ontstaat hij)?
A the pulmonary artery (low in oxygen)
B the aorta (because the aorta contains blood rich in oxygen and nutrients)
C the pulmonary vein (going back to the heart)
D the vena cava (low in oxygen)
41. What causes coronary arteries to become narrower when you have atherosclerosis?
in the artery fat gets stuck to the vessel wall
42. Explain what happens during a heart attack.
a blood clot (from somewhere else gets stuck in the narrowed coronary artery – then
the heart muscle cells can’t get oxygen and stop respiring and stop contracting – the
heart stops beating - you die
43. What causes death in case of a heart attack (step by step)?
see above – the brain doesn’t get oxygen because the blood doesn’t flow anymore – if
the brain stops working you’re officially dead
Section 9 – measuring blood pressure
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44. Explain that the blood pressure in your arteries is not constant but changes during
every heart beat.
during the systole of the ventricle the blood is pushed through the arteries by the
beating of the heart – at that point the pressure in the blood vessels (blood pressure)
is high– during the diastole of the ventricle the heart doesn’t push the blood through
the arteries so – the pressure in the vessels is low – like the waves of the sea
45. When is the pressure highest in your arteries?
it is highest during the systole - the contraction of the ventricle
46. When is the pressure lowest in your arteries?
when the ventricle is relaxing, ventricular diastole
47. What do you actually hear when you hold a stethoscope on the hollow of your elbow
while determining your blood pressure?
the collapsing (closing) of the artery – the pressure of the cuff closes the artery – but
when the pressure in the artery is higher than in the cuff, the blood can lift the cuff for
a short while – when the pressure drops because the diastolic pressure is not high
enough to lift the cuff, the blood vessel collapses – the closing is the thud you hear
48. Explain that you don’t hear vibrations anymore when the pressure in the cuff is below
the diastolic pressure.
when even the diastolic pressure is high enough to lift the cuff so that the arteries
don’t close at all, there will be no thud; if the vessel stays open you can’t hear it close
section 10 – Lymph
49. What would happen if the excessive (overtollige) interstitial fluid wasn’t removed by
the lymphatic system?
if it wasn’t removed, the amount of interstitial fluid in the tissues would continuously
increase – more fluid leaves the capillary than re-enters the capillary at the end of the
tissue – therefore, fluid is left behind in the tissue – if is isn’t removed by the lymph
vessels, it would become more and more
50. How is lymph fluid moved along the lymphatic vessels?
the same way as in veins: by using valves and contraction of muscles
51. If lymph nodes in your arm pit start to swell, where would you expect to find a
inflammation? upstream – meaning, there where the lymph fluid came from – in this
case somewhere in your arm or hand
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52. Does the fluid in the lymphatic system flow around in circles? If not, how does it flow?
No, because it only collects fluid at the tissues and delivers it to the circulatory system
somewhere close to the heart – if it circulated, the lymph fluid would end up where it
came from
Figure 10.
how do
valves
function
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