Download PP 2 Circulation 1- highlighted

 Transport system to carry oxygen and nutrients to all
of the cells in the body.
 Takes away waste products (like CO2)
 Heart pumps blood continuously
 Uses a network of blood vessels (to the cells / at the
cells / back to the heart)
(In diagrams – red = oxygenated blood – blood that has
oxygen & blue = deoxygenated blood – blood that is
carrying CO2))
 From the Heart – pumps blood to (at the same time):
Aorta – an artery that carries blood (oxygenated) out
of the heart and then through smaller arteries to the
rest of the body.
2. Pulmonary artery (actually a vein)- carries
(deoxygenated) blood to the lungs.
1.
 To the heart from the body at the same time:
Pulmonary vein: (actually an artery) carries
oxygenated blood to the heart from the lungs.
2. Vena Cava – carries the rest of the deoxygenated
blood from the body to the heart.
1.
 Double circulatory system – If you follow 1 blood cell –
you will notice that it is in the heart 2 times. One as
oxygenated blood and the other as deoxygenated blood
in 1 cycle.
 Oxygenated blood gives O2 to the cells and becomes
deoxygenated (has CO2) when it comes back to the
heart
 O2 is needed for cell respiration
 The heat has valves that allow the blood to flow only
in 1 direction.
 The veins also have valves that stop the blood to flow
backwards.
 Blood flows out of the heart in Arteries (like the Aorta)
under high pressure
 Blood flows back to the heart in Veins (Vena Cava)
under low pressure.
 Blood moving out of the heart is under high pressure.
 As it gets further away from the heart the pressure
reduces.
 When pressure is high – the movement of the blood is
fast
 When pressure is low – movement of the blood is
slower
Pulmonary
Artery
Vena Cava
Aorta
Right
Atrium
Left
Atrium
Left
Ventricle
Right
Ventricle Septum
Tricuspid Valve
Pulmonary Vein
Semi Lunar valve
Bicuspid Valve
 Heart is made of cardiac muscles that contract and
relax
 60 heart beats per minute (on an average)
 Energy for the heart comes from fatty acids rather than
glucose (glucose is for the rest of the body)
 Fatty acids are brought to the heart via Coronary
arteries (that supplies nutrients to the heart)
Right Side:
Blood enters the heart through two large
veins, the inferior and superior vena cava,
emptying oxygen-poor blood from the body
into the right atrium.
Left Side:
The pulmonary vein empties oxygen-rich
blood, from the lungs into the left atrium.
Heart valves: The tricuspid and bicuspid valves stay shut until the right and
left atriums are full. The pressure of the blood being full in the atrial
chambers pushes the valves open and then the ventricles fill up.
Right Side:
Blood flows from your right atrium into your
right ventricle through the open tricuspid valve.
When the ventricles are full, the tricuspid valve
shuts. This prevents blood from flowing backward
into the atria while the ventricles contract
(squeeze).
Left Side:
Blood flows from your left atrium into your left
ventricle through the open mitral valve. When
the ventricles are full, the mitral valve shuts. This
prevents blood from flowing backward into the
atria while the ventricles contract (squeeze).
Heart Valves: The tricuspid and bicuspid valves stay open till the ventricles are full.
When the ventricles contract, the pressure of the blood pushing against the bicuspid
and tricuspid valves force it to shut. This allows the atrial chambers to fill again as
Blood is coming in via the Vena cava and the pulmonary vein.
Right Side:
Blood leaves the heart through the semilunar
valve, into the pulmonary artery and to the lungs.
Left Side:
Blood leaves the heart through the aortic valve,
into the aorta and to the body.
This pattern is repeated, causing blood to flow
continuously to the heart, lungs and body.
When the ventricles are full, they force the Semilunar valves to open. This forces
the blood into the Aorta (from the left ventricle) and into the Pulmonary Artery
(from the right ventricle).
 Coronary Arteries -Deliver blood to muscles of the
heart
 Disease – these arteries are blocked or damaged and
therefore can not supply the heart with the nutrients it
needs.
 How?
- Cholesterol builds up in the walls partly blocking the
arteries
Walls of the arteries – less elastic (unable to expand
and contract as normal).
Increases the chances of blood clot near the blocked
area. The blood clot can move into a narrow area of the
artery.
 When the heart is unable to get blood and nutrients
due to this it stops functioning properly.
 This is a heart attack.
Superior Vena
Cava
Aorta
Left
Pulmonary
Artery
Right
Pulmonary
Artery
Left Pulmonary veins
Coronary Artery
Anterior Vena
Cava
Coronary Vein
Causes
Preventative Measures
• diet in high saturated fats cause
cholesterol to be deposited in the
coronary arteries
•Too much salt in diet
•Smoking
•Stress
• regular exercise
• well balanced diet
• less salt
• no smoking