Transcript Chapter 10 and 11 PowerPoint

Cardiovascular and
Blood
Chapters 10 and 11
Cardiovascular
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The function of the cardiovascular
system is transportation.
Blood is the transport vehicle.
Materials that are transported range
from oxygen from the lungs, nutrients
from digestion, or hormones from the
endocrine system.
Heart
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The heart is the major pump of the
cardiovascular system.
This hollow cone shaped organ is
approximately the size of a closed fist.
Flanked by both lungs
Not symetrical, apex points toward the left
hip.
Most of the heart lies on the left side of our
body.
Heart Coverings
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The heart is covered by the pericardium –
double layer serous membrane.
The membrane connects the heart to the
surrounding structures such as the sternum.
It also contains a slippery lubricating fluid
that allows the heart to move in an almost
frictionless environment.
Heart Wall
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The heart walls actually have three layers:
epicardium, myocardium, and
endocardium.
The epicardium is part of the serous
membrane we discussed.
Myocardium is the middle, actual cardiac
muscle that contracts.
Endocardium is the innermost layer that
lines the entire heart and continuous with
the inside layer of the blood vessels.
Heart Layers
Heart Chambers
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Our hearts have four chambers, two atriums
and two ventricles.
Atriums receive blood from the body or the
lungs.
They have no relative importance in the
pumping action of the heart, they mostly
receive blood under low pressure from the
veins in the body. Because of this they
have relatively thin walls.
Heart Chambers
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The two lower ventricles have a much
thicker wall.
This is due to the fact that this part of
the heart is in charge of pumping
blood to the lungs or the rest of the
body.
The left and right ventricles are
separated by the septum.
stop
Blood Flow through Heart
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Deoxygenated blood from the smaller
vessels collects in the superior and inferior
vena cava.
These two major veins empty this “used”
blood into the right atrium.
It is held here by one of the four
atrioventricular valves, aka AV valves,
specifically the tricuspid valve.
This keeps the movement of blood in one
direction only.
Blood Flow through the
Heart
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When the tricuspid valve opens, blood
falls into the right ventricle.
This is the first beat of the heart, very
gently pumping blood into the lower
chambers.
The second beat of the heart is
stronger and is accomplished by the
ventricle.
Blood Flow through the
Heart
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Blood in the right ventricle is pumped
up through the pulmonary valve and
into the pulmonary artery.
This artery takes the blood to the
lungs where it picks up oxygen and
releases carbon dioxide.
Reoxygenated blood then returns to
the heart through the pulmonary vein.
Blood Flow through the
Heart
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Blood reenters the heart in the left atrium.
It is kept here by the Mitral valve.
When the mitral valve opens blood empties
into the left ventricle, the strongest of the
four chambers.
When it pumps, blood flows through the
aorta and is distributed to the entire body.
Heart Sounds
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Characterized as Lub Dup
Signal the closing of the AV valves
Lub sound is heard when the valves close
after the emptying of the atria.
The Dup sound is heard when the ventricle
contracts and the semilunar valve closes.
Abnormal heart sounds are called murmurs.
Heart Beat
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Avg heart rate should be 70bpm
Tachycardia is a fast heart beat (over
100bpm), Bradycardia is a slow heart
beat (under 60bpm).
The heart is controlled by electrical
impulses.
When this electrical impulse fails, a
pacemaker can be used.
stop
Heart Circulation
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Even though the interior of the heart
is constantly bathed in blood, it
receives no nutrients in this fashion.
Nutrients are fed to the heart through
the coronary arteries. These branch
off of the aorta and wrap around the
heart, feeding it oxygen and nutrients.
Heart circulation
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If any of these heart arteries are
clogged or do not receive oxygenated
blood, heart tissue can die called an
infarction.
If left unattended, a myocardial
infarction, aka heart attack can occur.
Blood
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Carries everything that needs to be
transported around the blood.
– Nutrients
– Wastes
– Body heat
– Hormones
– Etc.
Blood
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Blood is the only liquid tissue.
It is made of both solid and liquid
components. Living blood cells
suspended in the nonliving fluid matrix
called the plasma.
Scientists can use a centrifuge to
separate the different elements of the
blood.
Solid Blood Elements
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Erythrocytes – red blood cells –
transports oxygen and carbon dioxide.
– 4-6 million cells per mL of blood
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Leukocytes – White blood cells –
protects the body from invaders
– 4-11 thousand
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Platelets – cell fragments that help in
clotting.
Liquid Blood Elements
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Plasma – 90% water, 10% nutrients
and plasma proteins.
Blood as a whole is slightly basic
Has the taste of iron due to
hemoglobin
It is also approximately 8% of your
body weight ~ 6 quarts
stop
Erythrocytes
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Ferry oxygen around the
body.
No nucleus, contain
hemoglobin
Central depression on both
side allows for more surface
area
Anemia is a decrease in
oxygen carrying ability
Sickle cell anemia is a
misshapen cell due to hemo
mutation
Leukocytes
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White blood cells are not confined to
the vessels, they can leave and help to
stop infections where needed.
They use positive chemotaxis to find
areas in need.
WBC can be produced above the
normal amount. Anything over 11,000
cells/mL is referred to as leukocytosis
ABO Blood Groups
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Blood transfusions can save lives, however,
they can be deadly if the right blood is not
chosen.
The RBC of each blood group has different
membrane proteins attached to them, called
antigens.
If the antigens on the transfused blood do
not equal those of the normal blood, the
immune system will respond and attack it.
ABO Blood Groups
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The immuno response in this case is
that the plasma will begin to clump
around the transfused RBC, turning
the blood into a gel which can block
small arteries. This can lead to organ
failure
ABO Blood Groups
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Type B – Anti A, can receive from B, or O,
19%
Type A –anti B, can receive from A or O,
32%
Type O –Anti A and B, universal Donor,
45%
Type AB –no plasma antibodies, can receive
any blood, 4%
Rh Blood Groups
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Another set of Antigens that can be
found on the surface of the RBC are
the Rh Factors, named after the
Rhesus monkey from which they were
discovered.
Rh+ you have the antigens, Rh- you
don’t.
Blood Typing
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To determine what
blood type a person
is you add anti A or
anti B to different
samples, if the
blood clots, the
blood contains that
antigen.
stop
Blood Vessels
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Blood vessels are the “one-way” highways
of our cardiovascular system.
Blood vessels that carry blood away from
the heart are called arteries
Blood vessels that carry blood toward the
heart are veins.
The interconnected series of tubes is called
the vascular system.
Vascular System
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Just like roads in New Jersey, our vascular
system has a series or “major highways,”
“side streets,” and “alleys” which
determine how much blood can flow
through at a given time.
The largest artery is the aorta, the largest
vein is the vena cava.
Capillaries are your smallest tubes,
allowing for only one blood cell to pass at
a single time.
Artery and Vein
Differences
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Arteries tend to have thicker walls due to
increased pressure near the heart.
Veins tend to have thinner walls because
the pressure is lower.
Veins tend to have a larger diameter as well
as valves.
– Valves are necessary since without blood
pressure, blood would never get back to heart.
Capillaries
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Capillaries only have a very thin tunica
intima. This allows for easy diffusion
of oxygen and nutrients from
capillaries to the surrounding tissue.
Because they are so thin they are
easily broken. Bruises.
Vital Signs
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Pulse and blood pressure are two vital signs
that doctors will often refer too.
The other two are respiration rate, and
temperature.
Pulse is measured by placing the fingers on
an artery close to the surface of the skin, as
the heart beats, the pressure in the vessels
push up on your fingers.
Avg would be 70-80 bpm
Blood Pressure
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Hypertension is high blood pressure
Hypotension is low blood pressure.
Caused by diet, chemicals,
temperature, amount of blood and
neural factors.