Transcript Parts of The Heart

Parts of The Heart
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The Atria (or Atriums)
-Receiving Chambers
The Ventricles
-Pumping Chambers
The Valves
-Prevents backflow
The Septum
-Divides the Heart
Right side = incoming blood
Left side = outgoing blood
ANATOMY OF THE HEART
ANATOMY OF THE HEART
Label the structures of the heart
from your handout.
Refer to your text P. 495
You have 10 minutes!
PATHWAY OF BLOOD
Trace the flow of a red blood cell as it
returns to the heart from the body's
cells.
PATHWAY OF BLOOD
1) a. superior vena cava or 1)b. inferior vena cava
2) right atrium
3) tricuspid valve—(AV valve)
4) right ventricle
5) pulmonary valve—(semilunar valve)
6) pulmonary artery (goes to lungs)
PATHWAY OF BLOOD
7)
8)
9)
10)
11)
12)
13)
pulmonary vein (from the lungs)
left atrium
bicuspid valve (left AV valve)
left ventricle
aortic valve (semilunar valve)
aorta
to the body’s cells
HEART SOUNDS
When you hear your heart beating, what are you actually
listening to?
Normal Sounds (48 sec):
http://www.youtube.com/watch?v=NeMJXMSkA7g
(3:30 min) http://www.youtube.com/watch?v=H04d3rJCLCE
What do blue vs. red areas represent?
Heart valves
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4 valves in the heart
– flaps of connective tissue
– prevent backflow
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____________________________
– between atrium & ventricle
– keeps blood from flowing back
into atria when ventricles contract
» “lub”
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SL
____________________________
– between ventricle & arteries
– prevent backflow from arteries into
ventricles while they are relaxing
» “dub”
AV
AV
Lub-dub, lub-dub
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Heart sounds
– closing of valves
– “Lub”
SL
» recoil of blood against
closed AV valves
– “Dub”
AV
AV
» recoil of blood against
semilunar valves
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Heart murmur
– defect in valves causes hissing sound when stream of
blood squirts backward through valve
Cardiac cycle
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1 complete sequence of pumping
– heart contracts & pumps
– heart relaxes & chambers fill
– contraction phase
» ______________
» ventricles pumps blood out
– relaxation phase
» ______________
» atria refill with blood
systolic
________
diastolic
pump
(peak pressure)
_________________
fill (minimum pressure)
110
____
70
Measurement of blood pressure
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High Blood Pressure (hypertension)
– if top number (systolic pumping) > 150
– if bottom number (diastolic filling) > 90
Control of Heart Rate
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contraction without brain input
Sinoatrial (SA) node, also called pacemaker cells
are nerve cells in the right atrium
SA node causes the atria to contract
sends electrical stimuli to the atrioventricular (AV)
node.
electrical stimuli are sent through two nerve fibres
called Purkinje fibres to the ventricles
causing them to contract.
Control of Heart Rate
Disorders of CV System
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Plaque
– Patchwork of cholesterol, calcium and fat
deposits that stick to interior walls
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Dangers of plaque build up
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Atherosclerosis
Heart attack
Arteriosclerosis
Sudden cardiac arrest
Atherosclerosis
Narrowing of the arteries resulting from
plaque building up inside the artery wall
 Blood pressure increases
 Sometimes flow completely blocked
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Heart Attack
Blood supply to heart tissue is slowed or
stopped
 Narrowing coronary arteries due to
atherosclerosis
 Heart usually does not stop beating
 Pain in upper chest, shortness of breath,
nausea
 Heart muscle can die
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Arteriosclerosis
Advanced stage of plaque buildup
 Deposits on artery wall harden
 Arteries lose elasticity and ability to stretch
 Decrease in BP and chance of blood clots
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Sudden Cardiac Arrest
Heart suddenly stops functioning
 Drowning, electrocution, trauma, choking
 Coronary heart disease most common
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CV Disorders
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Arrhythmia
– Irregular heart beat
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Hypertension
– High blood pressure
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Heart failure
– Heart cant pump blood efficiently or send blood with
enough force to body
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Aneurysm
– Bulge in artery wall
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Stroke
– Blood clot in artery going to brain
Cholesterol
A fat that is part of your cell membranes and
is used to synthesize hormones, bile and
vitamin D
 Liver manufactures
 Transported by two lipoproteins made of fat
and proteins
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– HDL and LDL
Lipoproteins
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HDL
– Good cholesterol
– Helps remove excess cholesterol from tissues
and arteries
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LDL
– Bad cholesterol
– Becomes part of plaque in arteries
– Found in food high in trans and saturated fats