CIRCULATION SYSTEM AND CARDIOVASCULAR DISEASES

READING ASSIGNMENT:
                    TEXT:  CHAPTER 42, PAGE 811 – 812, 814 – 826

I. Introduction

Open circulatory system
 

Closed circulatory system
(Cardiovascular system)

II. Components of Cardiovascular System

1. Atrium (atria, plural)

2. Ventricles

3. Blood vessels
a. Arteries
b. Arterioles
c. Capillaries
d. Venules
e. Veins

4. Single circulation:  A heart with two main chambers, one atrium and one ventricle.  (Fish)
 

5. Double circulation:  Three-chambered heart, two atria, one ventricle, and two circuits.  (Amphibian)
 

Pulmonary circuit
 

Systemic circuit
 
 
 
 
 
 
 
 

III. Mechanism and Structure of Double Circulation in Four-Chambered Mammalian Heart
 

 
 
 

1. Pulse (heart beat)

2. Heart murmur

3. Cardiac cycle

Systole

Diastole

4. Blood pressure

Measurement of blood pressure:

120/70

Systolic pressure

Diastolic pressure

5. Sinoatrial (SA) node (pacemaker)

6. Atrioventricular (AV) node

7. Electrocardiogram (ECG or EKG)

IV. Blood

A.  Components of Blood

1. Plasma

2. Cellular elements

a. Red Blood Cells (erythrocytes)
i. Structure
ii. Mammalian RBC
iii. Hemoglobin

b. White blood cells (leukocytes), five major types.

c. Platelets

 
B.  Stem cells and the replacement of cellular elements

 Pluripotent stem cells

 Leukemia and treatment

C. Blood clotting and Hemophilia
 

V. Cardiovascular Diseases

1.  The leading cause of death in the U.S. and most other developed nations.

2.  Heart attack
 
3.  Stroke

4.  Atherosclerosis

5. Hypertension (high-blood-pressure)

VI. Causes of Cardiovascular Disease and Ways to Maintain a Healthy Heart

GLOSSARY

Artery – A blood vessel that carries blood away from the heart to organs throughout the body.

Arterioles – Arteries branch into small vessels that convey blood to the capillaries.  These small vessels are called arterioles.

Atrium (atria, plural) – Chambers that receive blood returning to the heart.

Atherosclerosis – Growths of plaques develop on the inner walls of the arteries, narrowing their bore.

Blood pressure – The hydrostatic force that blood exerts against the wall of a vessel is called blood pressure.  The pressure is much greater in arteries than in veins and is greatest in arteries when the heart contracts during ventricular systole.

Capillaries – Microscopic vessels with very thin, porous walls are called capillaries.  The network of these vessels is called capillary beds.  Transfer of substances between the blood and the interstitial fluid occurs across the thin walls of capillaries.

Cardiac cycle – The heart alternately contracts and relaxes in a rhythmic cycle.  When it contracts, it pumps blood; when it relaxes, its chambers fill with blood.

Closed circulatory system (Cardiovascular system) – Blood is confined to vessels and is distinct from the interstitial fluid.  Materials are exchanged between the blood and the interstitial fluid bathing the cells. (Vertebrate)

Diastole – The stage of the heart cycle in which the heart muscle is relaxed, allowing the chambers to fill with blood.

Electrocardiogram (ECG or EKG) – A method to measure the electrical current produced during the heart cycle.

HDL – High-density lipoproteins. Reduce cholesterol deposition, good for our health.

Heart attack – The death of cardiac muscle tissue resulting from prolonged blockage of one or more coronary arteries, cut the oxygen supply to the heart.

Heart murmur - A defect in one or more of the valves in the heart, causing a condition known as murmur.

LDL – Low-density lipoproteins, associates with the depositing of cholesterol in arterial plaques, bad for our health.

Open circulatory system - Blood baths the internal organs directly, and no distinction between blood and interstitial fluid. (Invertebrates, Insects…)

Plaque – Smooth muscle layer of an artery thickens and becomes infiltrated with fibrous connective tissue and lipids, such as cholesterol.  They can become hardened by calcium deposits, which lead to arthersclerosis

Plasma – The liquid matrix of blood in which the cells are suspended.  90% is water.  Inorganic salts dissolved in blood in the form of dissolved ions to maintain osmotic balance and pH.

Platelets – Fragments of blood cells, about 2- 3 um in diameter, no nuclei and functions in blood clotting.

Pluripotent stem cells – Refer to cells originated from the red bone marrow.  These cells have the potential to differentiate into any type of blood cells or into cells that produce platelets.

Pulse (heart beat) – The rhythmic stretching of the arteries caused by the pressure of blood driven by the powerful contractions of the ventricles.

Sinoatrial (SA) node (pacemaker) – Located in the wall of the right atrium, near the point where the superior vena cava enters the heart.  It maintains the heart’s pumping rhythm by setting the rate at which all cardiac muscle cells contract.

Stroke – The death of nervous tissue in the brain, usually resulting from blockage of arteries in the head.

Systole – The stage of the heart cycle in which the heart muscle contracts and the chambers pump blood.

Veins – Blood vessel, which returns blood back to the heart.

Ventricles – Chambers that pump blood out of the heart.