3. Circulation
• The cardiovascular system is a network that distributes blood
containing oxygen and nutrients and collects wastes. It comprises
the heart, arteries, blood and veins.
• Every second the body requires a fresh supply of oxygen and food
that the tissues require on a regular basis. This is provided by the
blood. Blood flows constantly around the body to the extremities
delivering nutrients and oxygen to the cells and back to the heart. It
is a full round trip. This is termed (circulation) and all parts related
to circulation come under the heading Cardiovascular system.
Cardio meaning = heart and vascular meaning = blood vessels.
This system provides oxygen and nutrients to all parts of the body
and extracts carbon dioxide and waste products.
• It includes the following parts – Blood, heart, blood vessels
(arteries, capillaries and veins)
4.
5.
6. Components of blood
• complex fluid circulated by the pumping action of the
heart. It feeds every cell of the body.
• An average sized person contains around 5 litres of
bood.
• Functions:
• Transports oxygen and nutrients to all bodies tissues and
removes carbon dioxide and wastes.
• Protection of the body via the immune system and blood
clotting to prevent blood loss.
• Regulation of the body’s temp and fluid content of the
bodies tissues. Blood is part liquid, 55% is called plasma
and a solid part is made up of red blood cells and
white blood cells 45%.
7. Plasma
• Plasma contains proteins, nutrients, hormones, mineral
salts and wastes are all dissolved inside the plasma.
Plasma is responsible for nourishing tissues for their
survival and without blood tissues would die.
• Much of carbon dioxide and some oxygen are also kept
in plasma.
• Due to the high amount of water that is maintained in
plasma frequent hydration is required so that the blood
maintains it’s viscosity. When there is a lack of water in
plasma the blood volume drops and dehydration occurs.
8. Red blood cells
• Red blood cells are formed in bone marrow. (think back to the inside
structure of bone)
• They have a major role in the delivery of oxygen and carbon dioxide
around the body. They are the postmen of the body.
• They are made up of hemoglobin. This teams up with oxygen to be
carried from the lungs to the cells of the body.
• Red Blood cells really outnumber the white blood cells by nearly
700 to 1. Why???? This is a an easy one?
• They are killed and remade almost every second (except in some
people) and the ones that survive have a really long life of four
months.
• Women carry less hemoglobin in the blood therefore can not carry
as much oxygen.
• What are the implications of this????
9. White blood cells
• ! White blood cells are made in bone marrow and also in lymph nodes.
• These great little things provide our weaponry against all sorts of bacteria
and infections and disease.
• These are great little swimmers because they can swim against blood fow to
get to an infected area to start working.
• There are two types of white blood cells:
• Phagocytes = they engulf foreign material
• Lymphocytes = They produce antibodies to fight disease
• An example of a enemy that can get past white blood cells is HIV/AIDS = It
manages to suppress the action of white blood cells. Hence death
10. Platelets
• These are the materials that stop blood from continually flowing from
our body!
• Blood clotting is performed by platelets getting in the way of blood.
E.G if we have no platelets we would bleed to death from any cut or
hole in our body.
• So it makes sense when you are doing first aid that you should
perform the same function of platelets with compression.
• They are made up of bone marrow sections.
11. Structure and function of the heart
• A heart is a pumping machine and if it could dance it would be on “So you
think you can dance” due to it’s ability to keep rhythm.
• Without a heart blood would not move and therefore we would never get any
oxygen around the body and tissues of the body would die. The pump is
very similar to a water pump. Pressure creates movement and movement is
maintained with a rhythm continuously being pumped.
• The heart is provided protection by what section of the skeletal system???
• The heart beats around seventy beats per minute at rest and obviously
increases with work!
• The heart is the strongest machine in the world, and if you consider that in
one day it will pump 100000 times and only really breaks down due to
human lifestyle and nutrition you should have a rough understanding of it’s
importance in keeping you in my class.
• Put on the heart monitors and see your resting heart rate! See if you are
normal?
12. • The heart is made up of two major sections divided by a muscle. Each side
the left and the right has two chambers.
• Atria = Is the receiver of blood coming back to the heart in the upper
chamber
• Ventricles = lower section and is responsible for the pumping of blood away
from the heart.
13. • A system of four one way valves allow
blood to flow in only one direction. E.G
From the atria to ventricle.
14. Action of the heart
• The heart receives blood from the veins and pumps it to
the lungs through the rhythm mentioned before and
relaxation. This is termed cardiac cycle: This contains
two parts
• =Diastole (relaxation or filling of the blood from areas of
the body especially from the lungs? why) It fills the atria
ready to go on another journey around the body. Why
has it visited the lungs???
• = Systole (contraction or pumping) Firstly the atria
contracts to fully fill the ventricles then the blood is
pumped under pressure to the lungs and all parts of the
body. The rising pressure closes all atrio ventricular
valves and opens the artery valves so blood can be
spread to the rest of the body.
15. Heart beat
• The heart beats or contracts by small electrical impulses. This moves the
muscle of the heart.
• The first low thud heard when listening to a heart beat is the atria ventricular
valves closing and the second larger deeper thud is the pressure of the
blood being pushed out of the ventricular section of the heart at the end of
the systole phase.
• At the end of the systole phase the blood is pushed through the arteries and
this contracts and expands the artery walls. This is called a pulse! Yes that
thing people feel is the contracting and expanding of artery walls. It
represents blood being pushed along the artery walls so therefore the heart
working, eg why it is used in first aid.
• Pulse can be felt at any point in the body where an artery is located close to
the skin. E.G neck. (What artery is this????)
• Tricky question; Why should you not use your thumb to measure a
pulse????
16. Blood supply to the heart
• Coronary circulation = The actual heart is like
any other muscle or tissue in the body in the way
it actually requires blood to continually beat.
• Blood vessels are located all over the
(myocardium) = heart wall to feed the muscle of
the heart blood and nutrients.
• The heart has an extreme need for blood and
will attract 75% of oxygen as it passes through
especially during exercise.
17. Arteries
• Arteries are the main large highways that carry blood
away from the body. They are made of smooth muscle
that is wrapped by artery walls so they can take the high
pressure of blood as it gets pumped through the body.
• Blood pumped through the left ventricle passes through
one of the most important arteries; the aorta.
• At the same time the pulmonary artery is pumping
blood to the lungs to collect oxygen and it travels through
the right ventricle.
• These two major arteries branch into smaller arteries
called arterioles and then further into really small minute
blood vessels called capillaries.
18. Capillaries
• Capillaries are the link between arterioles (small branches of
arteries) and veins.
• In active tissues (muscle and or brain) capillaries provide a large
surface area to allow the transfer of materials between blood and
fluid surrounding the cells. This fluid is termed interstitial fluid)
• The capillaries have a really thin wall to allow oxygen, nutrients and
hormones that are travelling in the blood to pass easily into the
interstitial fluid thereby allowing there movement into the cells of the
body.
• SO NOW YOU KNOW THE SPECIFICS ON HOW OXYGEN
REALLY TRAVELS THROUGHOUT THE BODY AND REACHES
THE ACTIVE CELLS IN THE BODY. (AMAZING)
• These really thin walls in capillaries are truly amazing because as
well as allowing materials to leave they also allow some products in.
Try and think about what these products are????
• The above process is termed capillary exchange.
20. Veins
• The venules collect the deoxygenated blood (low
oxygen high carbon dioxide) blood from the capillaries
and transfer that deoxygenated blood to the veins.
• Veins have regular (valves) to prevent backflow of the
blood. There is extremely low pressure in the veins
therefore meaning blood flows against gravity.
• So with a small amount of pressure how does the blood
return back to the heart.
• Lets find out: Its called muscle pump. As the muscles
around the veins contract it squeezes the veins creating
the pressure required to allow blood to travel back to the
heart.
• Check out the next diagram for an explanation.
22. Veins continued
• Alright, now that you know how veins work, what was the point of
knowing????
• Well the way veins work impacts on how we recover after exercise
and also how our body reacts when standing still for long periods of
time or sitting down with feet placed on the ground.
• So the whole process of cooling down after exercise is effected by
how veins work. When you stop exercising the “muscle pump”
stops working therefore blood starts to pool and blood flow is
reduced. So what impact does this have on waste removal and or
oxygen delivery to working muscles.
• The same effect can be found when standing for a long time without
contracting the leg muscles. The veins will not be squashed and the
valves will not open, therefore the blood begins to pool. This means
the blood is not returning to the heart. This can eventually cause
fainting due to a lack of blood flow to the brain.
23. Circulation
• Hopefully you have remembered that the heart
has two major sections. Both sides work like
pumps with over lapping circuits.
• The right side of the heart receives
deoxygenated blood from every where around
the body and pumps it to the lungs; This
circulation pattern is closed and is termed
pulmonary circulation.
• The left side of the heart receives oxygenated
blood from the lungs and pumps it all around the
body; This is termed systemic circulation.
24. Resting Heart Rates
• A heart rate is the number of heart beats in one minute.
• Children naturally have a higher heart rate than adults.
• The resting heart rates improves linearly with improvements in
fitness. This then allows us to use the resting heart rate as a basis
to look at individuals fitness.
• Lots of things can affect heart rate, food, excitement, stress, age,
lifestyle choices and of course exercise.
• MHR = 220 – YOUR AGE? E.G = I am 26 years old so my MHR =
194 This obviously decreases with age. Why do you think this is the
case????
• This formula is very limited and is only used as a basic guide.
• So if we use RHR and MHR we can look at the effect of exercise on
the cardio vascular system.
26. Effects of Exercise on the Heart
• Lets look at the overhead to see how
exercising helps with our heart rate over
time. A good heart rate can mean a
healthy heart.
27. Blood Pressure
• The term blood pressure refers to the amount of pressure that is exerted by blood on
the blood vessels.
• The same as the heart has two phases blood pressure has the same = two phases.
Why????
• The two phases are = systolic and diastolic
• Systolic = it is the highest peak pressure recorded when blood is forced into the
arteries during the contraction of the left ventricle (systole)
• Diastolic = is the minimum or lowest pressure recorded when the heart is relaxing
and filling. (diastole)
• Blood pressure refers to the quantity of blood being pumped through the arteries
(cardiac output) and the difficulty in which the blood has getting through the arteries
(resistance to flow)
• Any increase in cardiac output will result in an increase in blood pressure.
• When blood volume increases e.g excessive water intake the blood pressure
increases and when we loose blood through excessive bleeding blood pressure
drops????????
• If the viscosity of blood is increased eg through dehydration then the resistance of
blood getting through the arteries is increased. So what happens to blood pressure.
• As fatty deposits are left on the arterial walls the artery walls become less elastic and
harder thereby making it harder for blood to flow.
28. Blood pressure
• Blood pressure can be recorded with a sphygmomanometer and is
measured in millimeters of mercury. It is shown as a fraction =
systolic over diastolic.
• At rest in a normal healthy person Systolic should be recorded as
between = 100-130mm and diastolic around = 60-80mm
• Blood pressure is impacted on by gravity and therefore posture. E.g
standing or lying down. Other things that impact blood pressure are
emotions, exercise and sleep. Why?
• Most of these are normal and healthy and reduce when resting.
• It along with resting heart rate are a great way for health workers to
determine the state of cardio vascular health.
30. Measuring Blood Pressure
• A sphygmomanometer comprises the following
parts, a cuff = inflates cutting blood flow in the
artery wall. The pressure is displayed on a =
gauge showing how much pressure is in the
artery wall, therefore how much pressure is
being applied by the artery. And a hose to allow
air into the cuff. Also a hand held pump to allow
pressure to be applied to the cuff. (this is an old
style one)
• So how does it work??? Find out on the next
page.
31. Measuring blood pressure
• Step 1 – Wrap the cuff around the persons arm, placing the
stethoscope at the end of the cuff.
• Step 2 – Make sure the person is sitting comfortable and is not
anxious.
• Step 3 – Apply pressure to the cuff by pumping the hand held pump.
Apply enough pressure so that blood is stopped in the artery.
• Step 4 – Slowly allow the pressure to drop while watching the
gauge.
• Step 5 – While the pressure is dropping listen for the first thud = this
is the systolic pressure and you should record the systolic pressure
when that noise first appears.
• Step 6 – Keep allowing the pressure to drop and watch the mercury
and when the thuds stops that means there is no more obstruction
of the artery and the gauge should be taken again. This will be a
diastolic reading.
• Step 7 – Never over inflate the cuff for extended periods of time???
Why?
• Step 8 – Always release the pressure slowly as a quick increase
may cause faintness or pain.
33. Respiration
• Structure and function of the respiratory system
• Every working cell in the body requires oxygen to survive
and function and the respiratory system is the post office
for delivery of this very special ingredient.
• The taking up of oxygen and or the removal of carbon
dioxide is termed respiration.
• Respiration involves oxygen being the catalysis for the
releasing of food in cells for energy.
• The respiratory system allows for the exchange of gases
between the atmosphere (where we breathe) and blood
(delivery system of oxygen)
• The basic system of the respiratory system are the lungs
and the passages that ventilate them.
34. Respiration
• When air is breathed in through the nose or mouth it
contains oxygen and carbon dioxide along with dust and
whatever else is out there. The nose warms and acts a a
filter (like on a vacuum cleaner) so why do we sneeze?
Bless you.
• Whether the air enters the nose or the mouth, it ends up
in the trachea (a solid pipe kept open by a ring of
cartilage) This pipe (trachea) then divides into two pipes
(the left and right bronchus) which lead to what? (We
have two of them)
• The inner lining of the air passages produce mucus
which collects dirt and any foreign particles. Little tiny
hairs move that dirt away from the lungs. (they are called
cilia)
35. Lungs
• The lungs consist of two big bag like
structures. One each side of the heart.
What protects them???
• The lungs have tiny air pockets that
branch of the bronchioles called (alveoli)
which have on them tiny capillaries.
• This is where the exchange takes place
between oxygen into the blood stream and
carbon dioxide into the atmosphere.
37. Lung Function
• Inspiration = This is the term that relates to
breathing in. In the phase the diaphragm
contracts and the ribs are pulled upwards and
outwards by the intercostals muscles.
• This pulls the walls of the lungs out and allows
the volume of breath to increase. This decreases
the pressure which allows air to rush in and fill
the lungs.
• What does the air contains and test yourself by
explaining what the air travels in.
39. Expiration
• Expiration = is the breathing out phase. In this
phase the lungs return their normal position by
the intercostal muscles allowing the lungs to fall
back. The volume of the chest cavity is then
reduced as air flows out.
• This increases the air pressure in the lungs and
creates a steady equal pressure inside and
outside the lungs.
• At rest we on average breathe at about 12-18
breaths per minute. Does this increase or
decrease with movement, age and certain
emotions?
40. The exchange of gases
• During inspiration the alveoli are supplied by oxygen rich air and low in
carbon dioxide. As the deoxygenated blood is arriving from the heart and
dropping off carbon dioxide the oxygenated blood is arriving and being
absorbed by alveoli.
• It is like two teams; one arriving on a bus for a holiday and one getting
picked up after having a holiday.
• The two difference in two concentrations between oxygen and carbon
dioxide in the air results in a pressure difference.
• Gases such as oxygen and carbon dioxide move from areas of high
concentration or pressure. (refer back to inspiration and expiration)
• Therefore oxygen moves across to the alveoli and transfers to the blood
where by it attaches to the haemoglobin in red blood cells.
• At the same time carbon dioxide makes the same journey into the lungs.
• This process is known as the exchange of gases. This process is the same
one that occurs in the capillaries and muscles.
• Not all oxygen is transferred to the blood and this is why we can hold our
breath and also breath oxygen into someone else when performing cpr.
42. Immediate effect of exercise on
respiration
• The respiratory system is extremely
affected by exercise. As the heart requires
more blood and is required to pump at a
faster rate the respiration system needs to
amp up.
• This means that the muscles of the body
can gain more oxygen and relieve more
waste products.
43. Immediate responses to exercise
• Number 1)
• Normally the body begins increases inhalation therefore
raising the amount of breaths per minute before exercise
actually starts. This is due to nerves or anticipation of the
upcoming event.
• The amazing thing is that just the thought of an activity
can increase our breathing rate. Why?????
• Number 2)
• Once exercise has begun and depending on the activity,
the rate and depth of breathing rapidly increases. This is
caused by two things =1) sensory receptors in the body
are activated. =2) there is more carbon dioxide in the
blood. Can you tell me why????? Which means the body
needs to breath more to increase this level.
44. Immediate responses to exercise
• Number 3) The increases in the rate of
breaths (termed frequency) and the depth
at which we breath is linearly related to the
intensity of the exercise.
• Tidal volume is the depth or exact
amount of air that is taken into the lungs in
one breath.
• Would a fit person have a larger or smaller
(tv)?
45. Done
• Well Done
• Now read the summary and complete the
following questions!
46. Questions for the wknd
• Outline pulmonary and systemic circulation. How could a
blockage in either of these systems affect health?
• Discuss the effect of exercise on the heart with specific
referral to the terms used when discussing heart
function?
• Outline blood pressure and explain what it is used for?
• Draw a diagram to show all components of the lungs.
Label all parts with an explanation of their function.
• Explain the gas exchange process?
• Extension: (if your mad keen for success) Write a
detailed story of a breath of air as it travels through
the body? Discuss how your role changes and
divides as the journey continues.
