Transcript Unit 3 - West-MEC

Unit 3
•The Cardiovascular
System
Components
• Cardiovascular
system is made up
of many different
areas of your body.
• Heart
• Blood Vessels
• Blood
• Circulatory System
• The lungs also
play a role in
helping the CV
System?
• What do the
lungs do to the
blood in our
body?
Components Cont.
• Each Component is vital
in allowing blood to
flow through our
bodies.
 With out all of them
working together
effectively our bodies
may not function
properly.
• Think of dominoes that
are all lined up together
if one of them falls they
all go down.
Heart
• Hearts job is to pump
oxygen and other nutrients
to all cells in the body.
• The HRT helps remove
waste and Carbon Dioxide
from out cells.
• This is done by continually
pumping blood throughout
the body.
• The HRT is the most
important muscle in our
body and can grow stronger
and weaker like any muscle.
Heart Structure
• HRT is about the size of your fist and located
on the left-center side of your chest in the
center of your lungs.
• The HRT is made up of four chambers. Each
chamber has a valve that opens and closes
with blood flow.
Blood Supply
for the Heart
The Muscular
walls of the HRT
are constantly
active and need
lots of oxygen and
energy from blood.
 The HRT has its
own network of
Blood Vessels
called Coronary
Arteries.
Blood Supply for
the Heart
There are 2 main
arteries (which carry
blood from the heart
to the body) that
cover the heart and
divide over its surface.
There 2 main veins
(which carry used
deoxygenated blood
back to the heart)
that also cover the
surface for the heart.
Blood Supply for
the Heart
The lower two
chambers have
much thicker
muscular walls
than the upper two
chambers.
There is a thin
layer of HRT
muscle that
separates the right
and left sides.
4 Chambers
The Right Atrium
receives
deoxygenated blood
from the body (head).
 The blood then
passes through a valve
and goes down to the
right ventricle.
From the Right
Ventricle the blood is
pumped to the lungs
where it gets oxygen.
Chambers Cont.
The Blood then comes
from the lungs through
veins back into the heart
in the Left Atrium.
The blood then passes
through a valve and makes
its way into the Left
Ventricle.
From the Left Ventricle
the blood that has come
from the lungs and is
oxygenated gets pumped
through the Aorta and
into the rest of the body.
Chambers Cont.
The blood then
goes through the
body and back to
the beginning of
the process.
The contracting of
the heart takes
about a second or
less.
Circulatory & Respiratory
The Heart
CV Diseases
ATHEROSCLEROSIS
• Fatty deposits (plaque) that
cause the walls of your
arteries to become
hardened and narrow.
• This restricts blood flow!
• Results may include stroke,
or blood clots.
Healthy Artery
Mid-Stage Atherosclerosis
Unhealthy Artery
Heart Attack
• Occurs when an area of the
heart muscle is deprived of
blood and oxygen.
• This happens because an
artery has been clogged and
tissue begins to die.
• Symptom include sharp
pain, tingling and numbness
in the left arm.
Heart Cont.
Strong Heart
• Has less fatty
deposits.
• Can pump more
blood using less
energy.
• Lower Resting Heart
Rate.
Weak Heart
• Enlarged bigger than your
fist.
• More fatty deposits
located on the surface
around it.
• Must use more energy to
pump the same amount
of blood as a healthy
heart.
H
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Blood
• The blood that flows
through this network of
veins and arteries is
whole blood,
which contains three
types of blood cells:
– red blood cells (RBCs)
– white blood cells (WBCs)
– platelets
• Red blood cells are
shaped like slightly
indented, flattened disks.
• RBCs contain the iron-rich
protein hemoglobin.
• Blood gets its bright red
color when hemoglobin
picks up oxygen in the
lungs.
• As the blood travels
through the body, the
hemoglobin releases
oxygen to the tissues and
turns dark red..
Blood
• The body contains
more RBCs than any
other type of cell,
and each has a life
span of about 4
months.
• Each day, the body
produces new RBCs
to replace those that
die or are lost from
the body.
Blood
Blood
• White blood cells are • Blood contains far fewer
WBCs than red blood
a key part of the
cells, although the body
body's system for
can increase WBC
defending itself
production to fight
infection.
against infection.
• WBCs, and their life spans
• They can move in
vary from a few days to
and out of the
months.
bloodstream to
• New cells are constantly
reach affected
being formed in the bone
marrow.
tissues.
Blood
Blood
• Platelets made in the bone
marrow.
• They help in the clotting
process.
• When a blood vessel
breaks, platelets gather in
the area and help seal off
the leak.
• Platelets survive only
about 9 days in the
bloodstream and are
constantly being replaced
by new cells.
• A clot begins to form when the
blood is exposed to air.
• The platelets sense the presence
of air and begin to break apart.
• They react with the fibrinogen
to begin forming fibrin, which
resembles tiny threads.
• The fibrin threads then begin to
form a web-like mesh that traps
the blood cells within it.
• This mesh of blood cells hardens
as it dries, forming a clot, or
"scab."
Blood
• Blood contains other
important substances,
such as nutrients from
food that has been
processed by the
digestive system.
• Blood also carries
hormones released by the
endocrine glands and
carries them to the body
parts that need them.