Transcript Blood

Chapter 13
The Cardiovascular System
Functions of the
Cardiovascular System
Brings blood containing
oxygen, nutrients, and
hormones to cells
 Transports CO2 and
other wastes away
from cells

Functions Continued
Fights infection
 Regulates body
temperature
 Helps stabilize pH and
ionic concentration of
body fluids.

Cardiovascular System
Components
Heart
 Blood
 Vessels

Arteries
 Veins
 Capillaries

The Heart


Is a muscular pump that moves blood
through the body
Is suspended in the pericardial sac

Aorta
Superior vena
cava
Left pulmonary artery

Left atrium
Right pulmonary
veins
Left pulmonary
veins
Right atrium
Inferior vena cava
Right ventricle
Left ventricle

Composed of
four chambers
Divided into right
and left halves
Made up of
cardiac
muscle cells
Pericardium


Protective sac of
connective tissue
Surrounds the
heart
 Filled with
fluid
Myocardium



The muscle of the heart
Strong and thick
Composed of
spontaneously
contracting cardiac
muscle fibers
Myocardium
(heart muscle)
shown in red
Epicardium
(Outer surface
of myocardium)
Endocardium
(Inner surface of myocardium)


Can conduct electricity
like nerves
It’s blood supply comes
from the coronary
arteries
Structures of the Heart
Chambers

Atria- (2) upper
chambers




Left atrium
Aortic valve
Right atrium
Mitral valve
Ventricles- (2) lower
chambers




Thin walled
Receive blood from veins
Send blood to ventricles
Pulmonary valve
Thick walled
Receive blood from atria
Pump blood out through
arteries
Left ventricle
Tricuspid valve
Septum
Right ventricle
Septum

A wall that divides heart into right and left
Structures of the Heart

Valves seen from above
Pulmonary
valve
Valves


Prevent backflow of blood
Keep blood moving in one
direction
Pulmonary veins
Tricuspid valve
Right atrium
Chordea tendinea

Mitral valve
Aortic valve
Located between the
chambers
Left atrium
Pulmonary valve
Structures of the Heart

Chordae tendinease
“Heart strings”
 Cord-like tendons
 Connect papillary
muscles to tricuspid
and mitral valves
 Prevent inversion
of valve


Papillary muscles

Small muscles that
anchor the cords
Papillary
muscle
Structures of the Heart
brachiocephalic artery
14
right pulmonary artery
13 right pulmonary veins
left common carotid artery
left subclavian artery
aorta 1
left pulmonary artery 2
pulmonary trunk 17
15 superior vena cava
6 aortic valve
12
right atrium
left pulmonary veins 4
left atrium (auricle) 3
mitral valve 5
pulmonary valve 16
11 tricuspid valve
9 right ventricle
10
inferior vena cava
papillary muscle
left ventricle 7
septum 8
© 2006 Merriam-Webster, Inc.
Cardiac Cycle

Refers to all of the events from
the beginning of one heart beat to
the beginning of the next heart
beat

When cardiac muscle contracts it
does so as a single unit, creating
a heart beat

One heartbeat - a cardiac cycle consists of two parts called
systole and diastole
Cardiac Cycle

Diastole is the
period of time
when the heart
relaxes after
contraction


Oxygenated blood from the
lungs fills the left atrium
Deoxygenated blood from
other parts of the body fills
the right atrium.

At the end of the
diastole, the
atria contract,
starting
the Systole
Cardiac Cycle

Heart Sounds

Two normal heart
sounds with each
heart beat


“Lub”- sound- due
to closure of the
atrioventricular
valves (mitral and
tricuspid)

“Dub”- sound- due
to closure of the
aortic valve and
pulmonary valve
described as a…..
Cardiac Cycle

Heart Rate - count of each heart beat




On average, a heart beats 72 times a
minute when at rest
Usually it is calculated as number
of contractions of heart (heart beats)
in one minute and expressed as
"beats per minute" (bpm).
The pulse is the most
straightforward way of measuring the heart rate
Heart rate is controlled by nervous system
Hearse on an
emergency
Cardiac Cycle
An electrocardiogram abbreviated as EKG
or ECG is a test that measures the electrical
activity of the heartbeat or one cardiac cycle.
Cardiac Conduction System


Why don’t the
atria and
ventricles
contract at the
same time?
Inefficient….
Blood would
not be moved
in one direction,
some would
flow backwards
Cardiac Conduction System

Includes:




SA node
AV node
Bundle of His
Purkinje fibers
Purkinje fibers
Cardiac Conduction System




Sinoatrial Node (SA node)
Located high on the right
atrium.
Pacemaker of the heart.
Causes the wave of
contractions
in the atria to
send blood
into the
ventricles
Cardiac Conduction System



Atrioventricular Node (AV node)
Located in the interatrial septum
close to the tricuspid valve
Carries the electrical impulse
from the SA node to fiber
bundles in the ventricles.

This causes the
ventricles to
contract from the
apex (bottom) up
squeezing blood up
and out
Cardiovascular
Circuits
Pulmonary Circuit
Lung
Pulmonary
artery
Pulmonary
vein
Right
atrium
Left
atrium
Vena
cava
Aorta
Right
ventricle
Left
ventricle
Systemic Circuit
oxygen-poor blood
oxygen-rich blood
Pulmonary Circulation

Pumps
blood
low in
oxygen
to the
lungs
to pick up
oxygen and
return to heart
Systemic Circulation


Oxygenated blood is pumped to
the body
cells thru
the aorta
and other
arteries
Blood low
in oxygen
returns to
the heart
Coronary Circulation


The coronary circulation consists of the
blood vessels that supply blood to, and
remove blood from the heart muscle
itself.
The vessels that
supply blood high in
oxygen to the
myocardium are
known as coronary
arteries.
Pathway of Circulation
Pathway of Circulation
14
16
14
15
1
7
13
6
6
8
9
5 12 10
2
3
11
4
1
It takes about And
1 min.so
foron…
blood
to make 1 complete cycle
Blood Vessels

Form a closed circuit
of tubes that carry
blood throughout the
body

Laid end to end, the
blood vessels in an
average human body
will stretch
approximately 62,000
miles……2.5 times
around the earth
Blood Vessels


Have characteristic
features
Are distinguished by
size, tissue layers
and direction of
blood flow
Blood Vessels

Arteries








Receive blood from
ventricles
Take blood away
from the heart
Usually carry
oxygenated blood
Thickest vessel walls
Withstand greater blood pressure
Are very elastic
Connect to capillaries
Aorta is the largest artery
Blood Vessels

Veins









Transport blood away from capillaries
Carry blood
toward heart
Take blood to atria
Have valves
Thinner vessel
walls with less
smooth muscles
than arteries
Can stretch a great deal
Have larger diameters
Usually carry de-oxygenated blood
Vena cava is the largest vein
Blood Vessels

The contraction of muscles compressing
veins helps push blood up through the leg
veins back to the heart. The valves allow the
blood to flow towards the heart only.
Calf muscle
relaxed
Calf muscle
contracts
Muscle
squeezes veins
Valves
OPEN
Veins constrict;
blood moves;
valves open
Valves
CLOSED
Veins dialated;
blood still;
valves closed
Blood Vessels

Capillaries
Smallest of blood vessels
 Only one cell thick (epithelial cell)
 Connect arteries to veins
 Bring oxygen
and nutrients
to cells
 Removes
CO2, urea,
and other wastes from cells
 Where blood is under low pressure and
moving slowly

C
O
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P
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S
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Blood Pressure
Blood pressure refers to the force
exerted by circulating blood on
the walls of blood vessels
The pressure of the circulating blood decreases
as blood moves through arteries, arterioles,
capillaries, venules, and veins
Blood Pressure
Blood pressure is most commonly
measured via a sphygmomanometer
(blood pressure cuff)
 Average blood pressure for
an adult is 120/80

Blood Pressure
Systolic pressure is defined as the
maximum pressure in the arteries
exerted during ventricular
contraction (which occurs near the
beginning of the cardiac cycle)
Diastolic pressure is the minimum
pressure exerted when ventricles
relax and fill (at the resting phase
or end of the cardiac cycle)
Blood pressure readings = S/D
Blood Pressure

A person's pulse is the throbbing
of their arteries as an effect of
the pressure waves (heart beat)

Pulse is used to denote the frequency of the heart
beat


Pulse is usually measured in
beats per minute.
In most people, the pulse is an
accurate measure of heart rate.
Blood Pressure
and




Vasoconstriction is narrowing of a blood vessel.
When a blood vessel constricts, the flow of
blood is restricted or slowed.
Blood pressure will increase
Vasodilatation is where blood vessels in the
body become wider
following relaxation
of smooth muscle
in vessel wall. This
will reduce blood
pressure - since
there is more room
for the blood.
Blood

The life stream of the body, affecting every
cell and
system we have.

The blood is an
accumulation of
many different
elements, each
working in a
specific way to
keep us alive.
Blood

A circulating
connective
tissue
consisting of
several types
of cells
suspended in
a fluid medium
known as
plasma.
Blood

Functions of blood:


Supply oxygen to tissues
Supply nutrients such as glucose, amino acids and
fatty acids to tissues

Removal of wastes such as CO2 ,
urea and lactic acid from tissues

Immunological functions,
including circulation of white
cells, and detection of foreign
material by antibodies
Blood

Functions of blood continued:
Messenger functions, including transport of
hormones and signaling of tissue
 Coagulation,
part of body's
self-repair
mechanism
 Regulation of
core body temperature
 Regulation of body pH and ion concentrations

Blood


What percent of your body is blood? 8%
How much blood do we contain?



On average 4-6 liters
We contain about a pint of
blood for every 15 pounds
of body weight
Composition of Blood:


What percent of your blood is
cellular? 45%
What percent of your blood is
plasma? 55%
Blood

What is plasma?
A clear, straw
colored fluid
 What percent
of plasma is
water? 90%
 What’s in plasma?

Plasma
(55% of whole blood)
Buffy coat leukocytes
and platelets
(<1% of whole blood)
Erythrocytes
(45% of whole blood)
Formed
elements





Dissolved gasses
Vitamins
Minerals
Salts
Nutrients




Layering of blood components in a centrifuged blood sample
Enzymes
Hormones
Waste products
Plasma proteins
Blood

The cellular components are:
red blood cells
(erythrocytes)
 white blood cells
(leukocytes)
 platelets
(thrombocytes)


Blood cells are
formed in bone
marrow
Blood
B
L
O
O
D
C
E
L
L
F
O
R
M
A
T
I
O
N
Blood

Red Blood Cell Characteristics







(RBC)- Erythrocyte
Biconcave disks
No nucleus
Contain the iron based pigment hemoglobin
which binds with oxygen to transport it
Life span about 120 days
5 billion/1mL of blood = most numerous
Are very small
Blood

To the right is a Wright's
stained peripheral blood
smear under 1000 X
magnification.

The average size of a red
blood cell is 7.2
micrometers in diameter.

To the right is an artist's
drawing showing the
biconcave shape of the
red blood cell.
Blood
How RBC’s transport
oxygen....Hemoglobin
.…the iron containing
pigment
Hemoglobin makes
red blood cells red
Blood

White Blood Cell Characteristics
(WBC)- Leukocyte
 No definite shape
 Have nucleus
 Protect body against infection
 Life span varies (3 days-a few months)

7,000/1mL of blood
 Numbers increase if
infection is present
 Larger than RBC’s

Blood

Types of white
blood cells:
Monocytes are the
largest
 Neutrophils are the
most numerous
 Lymphocytes are
produced by the
lymph tissue
 Basophils release
histamines

Blood
 Types
of white blood cells:
The role of a macrophage
is to phagocytize (engulf
and then digest) cellular
debris and pathogens.
When a cell undergoes
apoptosis, programmed cell
death, white blood cells
called macrophages
consume cell debris.
Blood

Platelet Characteristics:
Thrombocyte
 RBC fragments
 Irregularly shaped
 No nucleus
 150,000-400,000/1mL
 Life span about 7-11 days
 Have a sticky surface
 Responsible for blood
clotting (injury healing)

Blood

This is an actual picture of White Blood Cells,
in with some red blood cells. The platelets are
stained purple,
a T-Lymphocyte
white cell is
stained green,
and a Monocyte
white cell is
stained gold as
seen through a
scanning
electron
microscope.
Blood

Red blood cells and
platelets are the
most numerous.

Of the leukocytes,
neutrophils are the
most numerous

Lymphocytes are the
predominant cell type
responsible for
immune responses.
Blood Clotting
Steps in Blood Clotting:
Let’s simplify
 platelets clump
this shall we?
 platelets release thromboblastin
 thromboblastin
produces thrombin
 thrombin converts
fibrinogen into fibrin
 fibrin causes a clot

Fibrin
Blood Clotting

Blood vessel is injured.

Platelets clump at the
site and produce a
substance that produces
strands
of fibrin.

Fibrin strands help
to clog the opening
or hole in the vessel.
Blood Clotting
Needed to
stop
bleeding
(hemorrhage)
Blood Types


ABO Blood Groups:
Red blood cell membranes may
contain antigens – a substance
that triggers an immune response
in blood that does not contain the
same antigen.

Blood plasma may contain antibodies, specialized
proteins that bind to
non-self antigens to destroy them.

It is important to prevent the mixing
of red cells that contain an antigen with plasma that
contains the corresponding antibody.
Blood Types
Antigens
Blood Types
AntiBody
Donate
To
Receive
From
Type
Antigen
A
A
Anti - B A or AB
A or O
B
B
Anti - A B or AB
B or O
AB
A+B
Neither
AB
O
None
Both
Universal
O,A,B,AB
Donor
Universal
AB,A,B,O
Receiver
O
Blood Types
Blood Types
Blood Transfusion
 The process of
transferring blood or
blood-based products
from one person into
the circulatory system
of another

For blood loss due to
trauma, surgery, or
severe anemia

Can be life-saving
Blood Types
What Happens When Mixing Wrong Blood Type?

Antibodies in blood will attack the foreign blood.

They will cause the blood cells to clump…. agglutination.

Will stop the
blood from
moving.

Circulatory
system
shuts down
Blood Types: Rh Factor

An additional antigen found on the surface of red
blood cells.

Rh + Means that the person carries the
antigen.

Rh -
Means that
the person
DOES NOT
carry the
antigen.
Blood Types: Rh Factor
Percentage of the Population With Each Blood Type
Rh+
Rh-
O
38.5% 6.5%
A
34.3% 5.7%
B
8.6%
1.4%
AB
4.3%
0.7%
The Rh, or
rhesus,
factor was
discovered in
1940 when
testing blood
with a rhesus monkey.
The Rh system was named
after rhesus monkeys, since
they were initially used in the
research to make the
antiserum for typing blood
samples.
Blood Types: Rh Factor
Rh-negative
Woman with
Rh-positive
fetus
Rh-negative
Woman and
Rh-positive man
conceive a child
Cells from
Rh-positive
fetus enter
woman’s
bloodstream
Woman
becomes
sensitizedantibodies
( + ) from
to fight
Rh-positive
blood cells
In the next
Rh-positive
pregnancy,
maternal
antibodies
attack fetal
red blood
cells
Circulatory System Disorders
Heart Disease

Risk factors










Older age
Male gender
Cigarette smoking
High cholesterol
Diabetes
Stress
Obesity
Heredity
Physical inactivity
High blood pressure
Quitting smoking, a healthy diet and exercise may
reduce your risk of heart disease
Plaque in
coronary
artery
Circulatory System Disorders
Atherosclerosis



Starts with damage or injury to the inner layer of an
artery
Fatty deposits called plaque
build up in the arteries
This causes:
 Blockage
in artery
 Less
flexible
vessels
 High
Blood
Pressure
Circulatory System Disorders
Hypertension

High Blood Pressure
Makes the heart
and blood
vessels work
harder
Increases the
chance of heart
disease, heart
attack or stroke
Circulatory System Disorders
Heart Attack
acute myocardial infarction
 Interruption of oxygen
supply to the heart
 Causes death of
the heart muscle
 Leading cause of
death in both men
and women

Coronary Blockage
Circulatory System Disorders
Heart Attack

Symptoms









Chest pain
Squeezing or heavy pressure
on chest
Pain that radiates down left
shoulder and arm
Shortness of breath
Nausea or vomiting
Anxiety or Fainting
Lightheadedness - dizziness
Palpitations (feeling like your
heart is beating too fast)
Sweating, which may be
extreme
Circulatory System Disorders
Stroke
Interruption of oxygen supply to the brain
 Caused by:

A clot in an artery
in the brain
 Breakage of an
artery in the brain


Causes brain cells
to be deprived
of oxygen and die
Hemorrhagic stroke
blood vessel ruptures
Thrombotic stroke
blood clot in
cerebral artery
Circulatory System Disorders
Thrombosis/Embolism

Thrombosis is the formation of
a clot (thrombus) inside a blood
vessel, obstructing the flow of
blood
 Embolism occurs
when an object
(usually a blood
clot) migrates
from one part
of the body
(through
circulation)
and causes a blockage (occlusion) of
a blood vessel in another part of the body
Circulatory System Disorders
Hemorrhage


Hemorrhage is the medical term
for bleeding - the loss of blood
from the body
Hemorrhage generally becomes
dangerous, or even fatal, when
it causes hypovolemia (low blood volume)
or hypotension (low blood pressure).

Hematoma- a collection
of blood due to internal
bleeding
(burse)
Gingival Hemorrhage
Circulatory System Disorders
Hem philia

A rare inherited bleeding disorder in which
the blood does not clot normally

The person is missing or has low levels of certain
proteins in the blood called clotting factors
Usually occurs only in males
They suffer prolonged bleeding
even with minor injuries
Bleeding can occur internally,
in joints and
muscles,
which
causes
Swelling in left knee joint
swelling
and pain



due to spontaneous bleeding
Circulatory System Disorders
Anemia




A condition where there is an abnormally low
number of red blood cells circulating in the body or
when the blood does not have enough hemoglobin
The body's tissues are being starved of oxygen
Most common disorder of the red blood cells,
affecting (~) 3.5 million
Americans
There are different
kinds of anemia
 Iron Deficiency
 Vitamin Deficiency
 Hemolytic Anemias
 Sickle Cell Anemia
Circulatory System Disorders
Anemia

A person with anemia
will feel tired, weak,
breathless, and dizzy

They may have a pale
complexion, increased heart
rate, low blood pressure, and
difficulty concentrating

The severity of the symptoms
is related to the severity of
anemia
Iron Deficiency Anemia
Circulatory System Disorders
Sickle Cell Disease

Sickle cell trait- The person is
carrying the defective gene,
but also has some normal
hemoglobin

Sickle cell anemiaThe person has
most or all of the
normal hemoglobin
replaced with the
sickle hemoglobin
Circulatory System Disorders
Valve Disorders

Valvular Regurgitation

Valvular stenosis

A condition in which
there is a narrowing,
stiffening, thickening,
fusion or
blockage of
one or more
valves of
the heart.
Circulatory System Disorders
Heart Murmur



A whooshing sound between the heart beats
The whoosh is an extra noise that blood makes as it
flows through any of the heart's chambers or valves or
even through a hole within the heart
More than half of all children have a heart murmur at
some time in their lives and most of these don't mean
anything is wrong
Normal Heart Valve
Opened
Closed
Problems
Opening
Problems
Closing
Circulatory System Disorders
Heart Murmur

Innocent heart murmurs can occur
when blood flows more rapidly through the
heart - such as during physical activity or
exercise, pregnancy, fever, anemia, from
aging or even heart surgery



Over time, innocent heart murmurs may
disappear
Abnormal heart murmurs are caused
by structural defects in the heart….
congenital heart defects, valve
abnormalities, or holes in the heart
Some abnormal defects can be treated
with medicines while others require
surgical repair
Circulatory System Disorders
Aneurysm



Localized, blood-filled dilation
(bulge) of a blood vessel caused by
disease or weakening of the vessel
wall
Most commonly occur in arteries at
the base of
the brain and
in the aorta
Can burst and
lead to death
at any time
Blood Vessel Microscope Slide