Circulatory System

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Circulatory System
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Circulatory System

• Components
• I. Heart
• II. Blood Vessels
• Veins, Capillaries, and Arteries
• Components of Blood
• Lymphatic System
• Blood Type
• Circulatory Problems
• (Closed System)

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I. Heart

• A. Circulation
• Muscle contractions cause blood to pump
• Pulmonary Circulation -Blood pumped from right
  side of heart to lungs
• Systemic Circulation - Blood pumped to the rest
  of the body

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The Heart

• Heart
• B. Structure
• Composed mainly of muscle
• Pericardium - Protective layer surrounding the
  heart
• Myocardium muscle found in the heart walls,
  responsible for pumping blood
• Septum Divides heart into 2 halves,
• Restricts mixing of blood
• Each side has two chambers
• Atrium (Upper Chamber) Receives blood
• Ventricle (Lower Chamber) pumps blood out of
  the heart
• Contains Valves that keep blood flowing in one
  direction
• Pumps enough blood to fill an Olympic-sized
  swimming pool a year

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Superior Vena Cava Large vein that brings
oxygen-poor blood from the upper part of the body
to the right atrium
Aorta Brings oxygen-rich blood from the left
ventricle to the rest of the body
Pulmonary Arteries Bring oxygen-poor blood to the
lungs
Pulmonary Veins Bring oxygen-rich blood from each
of the lungs to the left atrium
Left Atrium
Pulmonary Valve Prevents blood from flowing back
into the right ventricle after it has entered the
pulmonary artery
Aortic Valve Prevents blood from flowing back
into the left ventricle after it has entered the
aorta
Right Atrium
Mitral Valve Prevents blood from flowing back
into the left atrium after it has entered the
left ventricle
Tricuspid Valve Prevents blood from flowing back
into the right atrium after it has entered the
right ventricle
Left Ventricle
Inferior Vena Cava Vein that brings oxygen-poor
blood from the lower part of the body to the
right atrium
Septum
Right Ventricle
Question What is the advantage of a 4-chambered
heart?
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I. Heart

• Coronary Artery
• Supplies the heart muscle itself with
• blood

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• C. Heartbeat
• Sinoatrial Node (Pacemaker)
• Located in the right atrium
• Cardiac muscles contract in waves causing blood
  to leave the atria into ventricle
• Stimulated by nerve impulse from the medulla
• Atrioventricular Node
• Location base of right atrium beginning of
  right ventricle
• Transfers impulse from atria muscles and
  transfers them to ventricle muscles
• Ventricles contract causing blood to leave heart

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I. Heart

• C. Heartbeat
• Each heartbeat is called a cardiac cycle two
  atria contract then two ventricles contract
  (systole), and the entire heart relaxes
  (diastole)
• A normal heart beats 70 times per minute.

• Makes a lub-dub sound as the valves of the
  heart are opening and closing.

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I. Heart

• 1. Electrocardiogram
• (ECG or EKG)
• A test that records the electrical activity of
  the heart.
• The P wave represents contraction (systole) of
  the atria.
• The QRS wave contraction of the ventricle
• The T wave
• The relaxation of the muscle (diastole)

Question What are some problems associated with
the Sinoatrial Node? How can it be fixed?
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(No Transcript)
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I. Heart

• 2. Pacemaker
• Abnormal heartbeats can be controlled by an
  artificial pacemaker that is run on batteries

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II. Blood Vessels
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II. Blood Vessels C. Arteries

• 4. Blood Pressure
• Definition Force that is exerted by the blood
  upon the walls of the blood vessels.
• a. Regulated in 2 ways
• Sensory neurons attached to blood vessels detect
  blood pressure
• If too low neurons (nerve cells) stimulate
  nervous system to increase heart rate
• If too high stimulate nervous system to
  decrease (slow down) heart rate
• Kidneys
• When blood pressure is high kidneys remove
  water from the blood
• When blood pressure is low kidneys keep water
  volume high in blood

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III. Components of Blood

• Blood is composed of
• 55 plasma
• 45 blood cells
• red blood cells
• white blood cells
• platelets

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III. Components of Blood
Plasma
Platelets
White Blood Cells
Red Blood Cells
Blood Sample that has been Centrifuges
Whole Blood Sample
Sample Placed in Centrifuge

• A. Plasma
• Composes 55 of blood volume Centrifuged Blood
• 90 water and 10 dissolved gasses, wastes,
  nutrients, salts and proteins (Plasma Proteins)
• Albumins, Globulins and Fibrinogen

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III. Components of Blood

• B. Red Blood Cells (Erythrocytes)
• Transport oxygen and carbon dioxide
• Uses Hemoglobin iron containing protein that
  binds to oxygen
• Disc shaped to increase surface area
• One milliliter contains 5 million

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III. Components of Blood

• C. White Blood Cells (Leukocytes)
• Fight infection
• 5 Types neutrophils, eosinophils, basophils,
  lymphocytes and monocytes (located in lymph
  vessels)
• Located in Circulatory and Lymphatic Systems

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White Blood Cells
Function Engulf and destroy small bacteria and
foreign substances Attack parasites limit
inflammation associated with allergic
reactions Release histamines that cause
inflammation release anticoagulants, which
prevent blood clots Give rise to leukocytes that
engulf and destroy large bacteria and
substances Some destroy foreign cells by causing
their membranes to rupture some develop into
cells that produce antibodies, which target
specific foreign substances
Cell Type Neutrophils Eosinophils Basophils M
onocytes Lymphocytes
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III. Components of Blood

• D. Platelets (Thrombocytes)
• More numerous than WBCs 250,000 platelets in a
  small drop of blood
• Much smaller than RBCs
• Are fragments of cells
• Made in the bone marrow
• Live 5 days
• Aid in forming blood clots
• Adhere to site of injury and release chemicals to
  help blood clot

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• IV. Lymphatic System
• A. Network of nodes, vessels and organs
• B. Primary function return fluid lost by the
  blood to the Circulatory System
• C. Contains fluid called Lymph
• D. Restricts backward flow by the use of valves
• E. Nodes are used to trap bacteria
• F. Organs
• Spleen
• Harbors Phagocytes removes damaged blood cells
• Thymus
• Location of matured T Cells

Superior vena cava
Thymus
Heart
Thoracic duct
Spleen
Lymph nodes
Lymph vessels
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V. Blood Types
Blood Type Antigens on RBCs Antibodies in Plasma Can Receive Blood From Can Donate To
A A Anti-B O and A A and AB
B B Anti-A O and B B and AB
AB AB None A, B, AB and O AB
O O Anti-A Anti-B O A, B, AB, and O
AB universal recipient (can receive all blood
types) O universal donor (can donate to all
blood types)
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Blood Type of Donor
Blood Type of Recipient
A B AB
O
A B AB O
Unsuccessful transfusion
Successful transfusion
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VI. Circulatory Problems

• Atherosclerosis Condition in which lipids
  collect under the inner lining of damaged artery
  walls, eventually narrowing or blocking the
  artery and obstructing blood flow.

Heart Murmur Whooshing sound caused by the back
flow of blood from the left ventricle across the
mitral valve back into the left atrium
Anemia A decrease in number of healthy red
blood cells
Atherosclerosis
Coronary Thrombosis (Heart Attack) Blockage of
coronary arteries preventing oxygen to reach a
particular area of the heart muscle
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VI. Problems Cont.

• Stroke Occurs when blood vessels leading to or
  in the brain clot or burst causing that area of
  the brain to die due to lack of oxygen

Leukemia cancer that originates in the blood
causes overproduction of leukocytes
Sickle Cell Anemia Genetic disorder,
resulting in misshaped red blood cells
Rheumatic Fever A serious inflammatory
condition which follows Streptococcal pharyngitis
(strep throat). Can damage valves in the heart.
Sickle Cell
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How is Blood Pressure Measured?

• b. Sphygmonometer
• Normal Blood Pressure 120/80
• 120 ventricles contract (systolic)
• 80 - ventricles relax (diastolic)
• c. Hypertension excessively high blood
  pressure, medical consequences (140/90 or
  higher), can be caused by alcohol, smoking, diet
  and distress

• Hypertension Video