Title: The Circulatory System
1The Circulatory System
Notes
2Lecture Outline Circulatory System
PowerPoint Notes
textbook questions
Keys
3(No Transcript)
4Functions of the Circulatory System
- Brings blood containing oxygen, nutrients, and
hormones to cells - Transports CO2 and other wastes away from cells
5Functions Continued
- Fights infection
- Regulates body temperature
- Helps stabilize pH and ionic concentration of
body fluids.
6Circulatory System
- Components
- Heart
- Blood
- Vessels
- Arteries
- Veins
- Capillaries
7The Heart
- A muscular pump
- Moves blood through the body
- Is suspended in the pericardial sac
- Composed of four chambers
- Divided into right and left halves
- Made up of cardiac muscle cells
8Pericardium
- Protective sac of connective tissue
- Surrounds the heart
9Myocardium
- The muscle of the heart
- Strong and thick
- Composed of spontaneously contracting cardiac
muscle fibers
- Can conduct electricity like nerves
- Its blood supply comes from the coronary arteries
10Structures of the Heart
- Chambers
- Atria- (2) upper chambers
- Thin walled
- Receive blood from veins
- Send blood to ventricles
- Ventricles- (2) lower chambers
- Thick walled
- Receive blood from atria
- Pump blood out through arteries
- Septum
- Wall that divides heart into right and left
halves
11Structures of the Heart
- Valves
- Prevent backflow of blood
- Keep blood moving in one direction
- Between the chambers
- At junctions of artery and chamber
12Structures of the Heart
- Chordae tendinease
- Heart strings
- Cord-like tendons
- Connect papillary muscles to tricuspid and
mitral valves - Prevent inversionof valve
- Papillary muscles
- Small muscles that anchor the cords
13Structures of the Heart
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14Cardiac 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
15Cardiac 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
16Cardiac Cycle
The term systole is synonymous with contraction
of a muscle.
- Atrial systole is the contraction of the heart
muscle of the left and right atria. Both atria
contract at the same time, sending blood into the
corresponding ventricle
- Ventricular systole is the contraction of the
muscles of the left and right ventricles, which
contract at the same time.
17Cardiac Cycle
- During systole the ventricles contract, forcing
the blood into the pulmonary artery to be
re-oxygenated in the lungs, and into the aorta
for systemic distribution of oxygenated blood
18Cardiac Cycle
- Lub- sound- due to closure of the
atrioventricular valves (mitral and tricuspid) - Dub- sound- due to closure of the aortic valve
and pulmonary valve
- Two normal heart sounds with each heart beat
- described as a..
19Cardiac 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
20Cardiac Cycle
- Sympathetic division increases heart rate
- Parasympathetic division decreases heart rate
- Heart rate increases when more food and oxygen
are needed by the cells, or when under stress
- Resting heart rate can be significantly lower in
athletes
21Cardiac Cycle
An electrocardiogram abbreviated as EKG or ECG
is a test that measures the electrical activity
of the heartbeat or one cardiac cycle.
22Cardiac Conduction System
- Why dont the atria and ventricles contract at
the same time? - Inefficient.Blood would not be moved in one
direction,some would flow backwards
23Cardiac Conduction System
- Includes
- SA node
- AV node
- Bundle of His
- Purkinje fibers
24Cardiac Conduction System
- Sinoatrial Node (SA node)
- Located high on the right atrium.
- Pacemaker of the heart.
- Causes the wave of
contractions in the
atria.
- Sending bloodinto the ventricles
25Cardiac 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
- The location of nerve fiber bundles cause the
ventricles to contract from the apex (bottom)
upsqueezing blood up and out
26Pathway of Circulation
- Oxygen-poor blood draining from the body through
veins into the superior and inferior vena cava
flows to the right atrium, through the tricuspid
valve, and into the right ventricle. - As the right ventricle contracts, oxygen-poor
blood passes through the pulmonary valve into the
pulmonary arteries and on to the lungs to receive
oxygen.
27Pathway of Circulation
- Oxygen-rich blood from the lungs enters the heart
through the pulmonary veins, passing into the
left atrium. - Then through the mitral valve to the left
ventricle. Contraction of the left ventricle
forces blood through the aortic valve into the
aorta. - Various arteries branch off from the aorta to
supply blood to all parts of the body.
28Pathway of Circulation
- Arteries branch into smaller and smaller vessels
(arterioles) - They eventually become capillaries, which supply
blood to all body parts - Capillaries merge into (venuoles) which join into
veins and carry blood back to the heart.
29Pathway of Circulation
30Pathway of Circulation
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It takes about 1 min. for blood to make 1
complete cycle
And so on
31CardiovascularCircuits
32Pulmonary Circulation
- Takes place on the right side of the heart.
- Pumps blood low in oxygento the lungs to
pick up oxygen and return to heart
33Systemic Circulation
- Takes place on left side of heart
- Oxygenated blood is pumped tothe body cells
thruthe aortaand otherarteries - Blood lowin oxygenreturns to the heart
34Coronary Circulation
- The coronary circulation consists of the blood
vessels that supply blood to, and remove blood
from the heart muscle itself.
- Although blood fills the chambersof the heart,
the muscle tissue of the heart is so thick
that it requires coronary blood vessels to
deliver blood deepinto the myocardium.
35Coronary Circulation
- The vessels that supply blood high in oxygen to
the myocardium are known as coronary arteries.
36Blood 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
miles2.5 times around the earth
37Blood Vessels
- Have characteristic features
- Are distinguished by size, tissue layers and
direction of blood flow
38Blood 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
39Blood Vessels
- Veins
- Transport blood away from capillaries
- Carry blood toward heart
- Take blood to atria
- Have valves
- Thinner vessel walls with lesssmooth muscles
- than arteries
- Can stretch a great deal
- Have larger diameters
- Usually carry de-oxygenated blood
- Vena cava is the largest vein
40Blood 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.
41Blood 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
42Blood Vessels
- A network of capillaries runs close to the cells
in every part of the body. The capillaries have
very thin walls which allows nutrients to diffuse
through into the tissues and waste products to
filter back into the capillaries.
43- C B
- O L
- M O
- P O
- A D
- R
- I V
- S E
- O S
- N S
- E
- O L
- F S
44Blood 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
45Blood Pressure
- Blood pressure is most commonly measured via a
sphygmomanometer(blood pressure cuff) - It uses the height of a column of mercury to
reflect the circulating
pressure
- Average blood pressure for an adult is 120/80
46Blood 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
47Blood Pressure
- Pressure waves move through the blood vessels
- 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
- It can be felt at neck, wrist, and other places
- Pulse is usually measured in beats per minute.
- In most people, the pulse is an accurate measure
of heart rate.
48Blood Pressure
vasodialation
Vasoconstricion
and
- Vasoconstriction is narrowing of a blood vessel.
- When a blood vessel constricts, the flow ofblood
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.
49Blood
- 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.
50Blood
- A circulating connective tissue consisting of
several types of cells suspended in a fluid
medium known as plasma.
51Blood
- 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
52Blood
- Functions of blood continued
- Messenger functions, including transport of
hormones and signaling of tissue - Coagulation, part of body's self-repair
mechanism - Regulation ofcore body temperature
- Regulation of body pH and ion concentrations
53Blood
8
- What percent of your body is blood?
- 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?
- What percent of your blood is plasma?
45
55
54Blood
- What is plasma?
- A clear, straw colored fluid
- What percent of plasma is water?
- Whats in plasma?
90
- Dissolved gasses
- Vitamins
- Minerals
- Salts
- Nutrients
- Enzymes
- Hormones
- Waste products
- Plasma proteins
Layering of blood components in a centrifuged
blood sample
55Blood
- The cellular components are
- red blood cells (erythrocytes)
- white blood cells (leukocytes)
- platelets (thrombocytes)
- Blood cells are formed in bonemarrow
56Blood
F O R M A T I O N
57Blood
- Red Blood Cell Characteristics
- (RBC)- Erythrocyte
- Biconcave disks
- No nucleus
- Contain the iron based pigment hemoglobinwhich
binds with oxygen to transport it - Life span about 120 days
- 5 billion/1mL of blood most numerous
- Are very small
58Blood
- 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.
59Blood
- How RBCs transport oxygen....Hemoglobin
.the iron containing pigment
Hemoglobin makes red blood cells red
60Blood
- 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 ifinfection is present
- Larger than RBCs
61Blood
- Types of white blood cells
- Monocytes are the largest
- Neutrophils are the most numerous
- Lymphocytes are produced by the lymph tissue
- Basophils releasehistamines
62Blood
- Types of white blood cells
When a cell undergoes apoptosis, programmed cell
death, white blood cells called macrophages
consume cell debris.
The role of a macrophage is to phagocytize
(engulf and then digest) cellular debris and
pathogens.
63Blood
- 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)
64Blood
- 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
electronmicroscope.
65Blood
- 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.
66Blood Clotting
- Steps in Blood Clotting
- platelets clump
- platelets release thromboblastin
- thromboblastin produces thrombin
- thrombin converts fibrinogen into fibrin
- fibrin causes a clot
67Blood 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.
68Blood Clotting
Needed to stop bleeding(hemorrhage)
69Blood Types
- ABO Blood Groups
- Red blood cell membranes may contain antigens
a substancethat 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.
70Blood Types
71Blood Types
Anti- Body
Receive From
Donate To
Type
Antigen
A
A
A or O
A or AB
Anti - B
B
Anti - A
B
B or AB
B or O
UniversalReceiver
Neither
AB
A B
AB,A,B,O
AB
UniversalDonor
O
None
Both
O
O,A,B,AB
72Blood Types
73Blood 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
74Blood 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.
- Circulatorysystem shuts down
75Blood 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.
76Blood Types Rh Factor
Percentage of the Population With Each Blood Type
The Rh, or rhesus, factor wasdiscovered
in1940 when testing bloodwith 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.
77Blood Types Rh Factor
Rh-negative Woman withRh-positivefetus
In the nextRh-positivepregnancy,maternalantibo
diesattack fetalred bloodcells
Cells fromRh-positivefetus enterwomansbloodst
ream
Rh-negative Woman and Rh-positive manconceive a
child
78Circulatory System Disorders
Heart Disease
- Risk factors
- Older age
- Male gender
- Cigarette smoking
- High cholesterol
- Diabetes
- Stress
- Obesity
- Heredity
- Physical inactivity
- High blood pressure
79Circulatory System Disorders
Atherosclerosis
- Starts with damage or injury to the inner layer
of an artery - Fatty deposits called plaquebuild up in the
arteries - This causes
- Blockage in artery
- Less flexible vessels
- High BloodPressure
80Circulatory System Disorders
Hypertension
Makes the heart and blood vessels work
harder Increases the chance of heart disease,
heart attack or stroke
81Circulatory 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
82Circulatory 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
83Circulatory 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 deprivedof oxygen and
die
84(No Transcript)
85Circulatory 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
86Circulatory System Disorders
Hemorrhage
- Hemorrhage is the medical term for bleeding -
the loss of blood from the body - Hemorrhage generally becomesdangerous, 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)
87Circulatory 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 bleedingeven with minor
injuries - Bleeding can occur internally, in joints and
muscles, which causes
swelling and pain
Swelling in left knee joint due to spontaneous
bleeding
88Circulatory 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 millionAmericans - There are different kinds of anemia
- Iron Deficiency
- Vitamin Deficiency
- Hemolytic Anemias
- Sickle Cell Anemia
89Circulatory System Disorders
Anemia
Iron Deficiency 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
90Circulatory System Disorders
Sickle Cell Disease
- Sickle cell trait- The person is carrying the
defective gene, but also has some normal
hemoglobin
- Sickle cell anemia-The person has most or all of
the normal hemoglobin replaced with the sickle
hemoglobin
91Circulatory System Disorders
Valve Disorders
- Valvular stenosis
- A condition in which there is a narrowing,
stiffening, thickening, fusion
or blockage of
one or more valves of
the heart.
92Circulatory 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
Problems Opening
Problems Closing
Normal Heart Valve
Closed
Opened
93Circulatory 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
94Circulatory 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
ofthe brain and in the aorta - Can burst andlead to deathat any time
95Blood Vessel Microscope Slide
96Check This Out
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GLB1969-53,GGLBen26sa3DN - This has a lot of good info