Download Circulatory System - POLYTECH High School

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1. To
2. To
body
3. To
4. To
supply oxygen to every cell of the body
supply nutrients to every cell of the
remove wastes
remove carbon dioxide
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Blood
◦ Carries nutrients and wastes
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Heart
◦ Pumps the blood
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Vein/arteries
◦ Carries the blood to and from the body tissues
◦ Laid end-to-end would stretch 70,000-93,000
miles
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Lungs
◦ Exchange carbon dioxide for oxygen in the blood
stream
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8% of body weight
5x thicker than water
~ 100.4° F
Dark red (bluish) when depleted, bright red when
oxygenated
Components
◦ Plasma
 Red blood cells
 White blood cells
 Platelets
◦ Fat globules
◦ Chemical substances (carbs, proteins, hormones)
◦ Gases (O2, CO2, N)
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Red blood cells
◦ Carry oxygen and carbon dioxide
◦ Contains hemoglobin, which carries the oxygen
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White blood cells
◦ Fight infections
◦ Fight cancer
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Platelets
◦ Responsible for clotting
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Carry blood AWAY from the heart to the body tissues
◦ Typically this blood is enriched with oxygen and nutrients
(*there is one exception)
Largest artery – the aorta
◦ comes directly from the heart
◦ branches into smaller and smaller arteries as it goes away
from the heart and into the limbs, head, and skin
Smallest artery – the capillary,
◦ groups with other capillaries to form capillary beds
◦ site of exchange of nutrients and wastes between the blood
and the body tissues
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Aorta branches into:
Thoracic/abdominal aorta to:
◦ Common Iliac arteries (hips/pelvis) to:
 Femoral (upper leg) and tibial (lower leg) arteries
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Arch of aorta branches into:
◦ Carotid and vertebral arteries (neck/head)
◦ Subclavian arteries (upper chest/upper arms) to:
 Axillary (under arm) and brachial (upper arm) arteries
to:
 Ulnar and radial (lower arm) arteries
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Structure – 3 layers
◦ Muscle tissue
◦ Elastic fibers
◦ Connective tissue
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Each heartbeat pushes blood into the arteries,
which expand to hold the blood, then contract
behind it as the heart pumps the blood to the
next section
The structure prevents the arteries from
collapsing when they are broken
◦ The arteries do constrict to reduce the size of the
opening in order to minimize blood loss
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Carry blood back TO the heart
◦ Typically this blood is depleted of oxygen and is
carrying wastes
The largest vein is called the vena cava
◦ Inferior vena cava – blood coming from the lower
body
◦ Superior vena cava – blood coming from the
upper body
The smallest vein is called a venule
Venules connect with the capillary beds, then
combine again and again until they form the
largest veins
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Lower Body:
◦ Greater and lesser saphenous to:
 Femoral and deep femoral veins to:
 Common iliac veins to:
 Inferior vena cava to the heart
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Upper Body/Head:
◦ Axillary, brachial, and cephalic veins to:
 Subclavian and jugular veins to:
 Superior vena cava to the heart
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Structure is similar to arteries
Blood pressure in the veins is less than in the
arteries
◦ The walls are thinner, less elastic, and less rigid and
will collapse if not filled with blood
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The pressure in the veins is barely able to
overcome gravity
◦ In order to avoid pooling of blood or backflow in
the veins, they have valves that hold the blood in
place until the pressure builds up sufficiently to
move the blood towards the heart
◦ Veins rely on help from skeletal muscles to function
ARTERY
VEIN
Inner lining of
elastic tissue
Valve
Elastic layer
Smooth muscle
layer
Connective tissue
layer
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The primary organ of the circulatory system
An involuntary muscle
A bit larger than a man’s fist
Located to the left of the sternum, between
the 2nd and 5th ribs
◦ Sits between the lungs
◦ Sits within the cardiac impression, which is a space
made by a notch in each lung
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The heart is enclosed within a membranous
sac called the pericardium, which protects the
heart and anchors it in place
◦ Fibrous outer layer
◦ Serous inner layer
◦ Between the 2 layers is a watery lubricant that
minimizes friction when the heart beats
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Superior vena cava
Pulmonary veins
Right atrium
Tricuspid valve
Right ventricle
Inferior vena cava
Aorta
Pulmonary artery
Left atrium
Semi-lunar valve
Mitral valve
Left ventricle
Cardiac muscle
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Each half of the heart
has 2 chambers:
The atrium
◦ Upper chambers
◦ Blood enters from body
or lungs
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The ventricle
◦ Lower chambers
◦ Blood leaves for lungs or
body
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Superior vena cava
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Inferior vena cava
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Pulmonary artery *
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Pulmonary veins*
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Aorta
◦ Brings depleted blood from
head and upper torso and
extremities
◦ Brings depleted blood from
lower torso and limbs
◦ Carries depleted blood to
the lungs
◦ Carries newly oxygenated
blood from lungs to heart
◦ Carries oxygenated blood
to the body
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Purpose of valves – to allow
the blood to flow in only one
direction
Tricuspid valve - 3 flaps
◦ Allows blood to flow from right
atrium into right ventricle
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Pulmonary valve
◦ Allows blood to flow from right
ventricle into pulmonary artery
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Mitral valve – 2 flaps
◦ Allows blood to flow from left
atrium into left ventricle
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Aortic (semi-lunar) valve
◦ Allows blood to flow from left
ventricle into aorta
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Body → Inferior &
superior vena cava →
Right atrium →
Tricuspid valve → Right
ventricle → Pulmonary
valve → Pulmonary
artery →Lungs →
Pulmonary veins → Left
atrium →Mitral valve →
Left ventricle → Aortic
semi-lunar valve
→Aorta →Body
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Body →
Inferior & superior vena cava →
Right atrium →
Right Ventricle →
Pulmonary artery →
Lungs →
Pulmonary veins →
Left atrium →
Left ventricle →
Aorta →
Body
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The movement of blood from the heart to the
air sacs in the lungs and back to the heart
Necessary for the blood to exchange carbon
dioxide for oxygen
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1. Air is taken into body
through mouth and nose
2. Passes through larynx
and down trachea
3. Passes into bronchi
(air tubes)
4. Continues into
bronchioles (smaller air
tubes)
5. Disperses into alveoli
(small, thin air sacs)
where it waits to
exchange oxygen for
carbon dioxide
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Right ventricle pumps depleted blood into
pulmonary artery *
Pulmonary artery splits into right and left
branches and pass into the lungs
◦ Right artery is wider and longer than the left artery
and the right lung is larger (3 lobes) than the left
lung (2 lobes)
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The pulmonary artery divides at the lungs
into smaller and smaller capillaries until they
end in large capillary beds surrounding the
alveoli
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A very thin membrane separates the
capillaries from the air sacs
◦ As a blood cell moves down the capillary, CO2
diffuses through the membrane into the alveoli and
O2 passes from the alveoli to the blood cell
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The newly oxygenated blood passes out of
the capillary beds and is taken up by the
venules, which take the blood up to the right
and left pulmonary veins*
The veins unite to form 2 main trunks from
each lung and empty the oxygenated blood
into the left atrium of the heart
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Purpose of circulatory system
Components of circulatory system
Facts about the blood
Function of arteries
◦ Largest artery and it’s location
◦ Smallest artery and it’s location
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Function of veins
Differences between arteries and veins
◦ Differences in structure
◦ Differences in pressure
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Components of the heart
How to label the heart
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Path of blood flow from the body, through
the heart and lungs, and back into body
Path of blood flow through lungs
How CO2/O2 exchange occurs