The Cardiovascular System

Q - How many liters of blood does the adult human body contain?
A.5 liters
B. 10 liters
C. 15 liters

A – A. 5 liters
• 5.3 quarts
• 7-8% of a person’s body weight

Q - How long does a red blood cell survive in the bloodstream?
A.120 days
B. 1 year
C. Forever

A – A. 120 days
• As red blood cells age, they are removed by microphages in the liver and spleen

Q – What is hemoglobin?
A. A chemical that stimulates the production of blood cells
B. A molecule specially designed to hold waste products and remove them from the body
C. A molecule specially designed to hold oxygen and carry it to cells that need it

A – C. A molecule specially designed to hold oxygen and carry it to cells
• that need it oxygen throughout the body

Q – What is a hematocrit?
A. The measure of red blood cells in the blood.
B. A hormone that stimulates production of blood cells.
C. The nucleus of a red blood cell.

A – A. The measure of red blood cells in the blood.
• The ratio of cells in normal blood is 600 red blood cells for each white blood cell and 40 platelets.

Q – How does blood get its red color?
A. From proteins located in the bone marrow.
B. From the waste products in the blood.
C. From the iron in hemoglobin.

A – C. From the iron in hemoglobin.
• Each molecule of hemoglobin contains four iron atoms, and each iron atom can bind with one molecule of oxygen.

Q – What is the function of white blood cells?
A. To carry oxygen from the lungs.
B. To fight infection.
C. To create clots.

A – B. To fight infection
• White blood cells help fight infection in the body.

Q – What does it mean when there’s an increase of white body.
B. Your body just finished fighting an infection.
C. There’s no oxygen in the blood.

A – A. There’s an infection somewhere in the body.
• A normal adult body has 4,000 to 10,000 white blood cells per microliter of blood

Q – What substance makes up the majority of plasma?
A. Proteins
B. Water
C. Electrolytes

A – B. Water
• Plasma is 90% water
• The other 10% dissolved into plasma are materials such as proteins, electrolytes, carbohydrates, cholesterol, hormones, and vitamins.

Q - If you are a universal donor, what blood type do you have?
A. Type A
B. Type AB
C. Type O

A – C. Type O
• People with Type O blood are universal donors, because anyone can get a type O blood transfusion
• Someone with Type AB blood is a universal recipient because this blood has no antibodies that could react with donated blood
• More than a third of the US population has
Type O+

Q – How does blood enter the heart?
A. Pulmonary artery
B. Superior vena cava & inferior vena cava
C. Mitral valve

A – B. Superior vena cava and inferior vena cava
• No blood gets into the heart without passing through the superior vena cava and the inferior vena cava first.

Q – How many gallons of blood does the heart pump in a day?
A. 20 gallons
B. 200 gallons
C. 2,000 gallons

A – C. 2,000 gallons
• 2,000 gallons = 7,571 liters

Q – How many times does your heart beat each day?
A. 1,000 times
B. 10,000 times
C. 100,000 times

A – C. 100,000 times
• The heart beats 100,000 times daily to supply every cell in the body with freshly oxygenated blood

The Cardiovascular System
Major functions of this system:
 delivers oxygen
 removes carbon dioxide & other waste products
Simply the job of the cardiovascular system is transportation.

Heart Anatomy
• Roughly the size of a clenched fist.
• Hollow and cone–shaped
• Weighs less then one pound
• Beats about 100,000 times in ONE day and about 35 million times in a year.

Orientation of the Heart
Apex – Bottom pointed part of heart. Points toward the left hip and rests on the diaphragm.
Around the 5 th intercostal space
*Maximal impulse, where heart sounds are loudest
Base – Posterosuperior aspect of the heart. Points toward the right shoulder and lies beneath the second rib.

Heart Anatomy
Where is the heart located?
•Superior surface of diaphragm
•Enclosed within the mediastinum
•Flanked on either side by the lungs
•Anterior to the vertebral column, posterior to the sternum

Coverings and walls of the heart
The lining of the pericardial cavity is a serous membrane called the pericardium.
• Surrounds heart and roots of the great vessels
Two layers:
1. Fibrous pericardium (tough, white fibrous tissue)
2. Serous pericardium (thin, smooth inner portion)

Covering of the heart
The fibrous pericardium is a dense connective tissue it:
A. protects the heart
B. anchors the heart to the surrounding walls
C. prevents the heart from overfilling with blood

Covering of the heart
Deep to the fibrous pericardium is the two-layer
serous pericardium .
1. Visceral pericaridum or epicardium - Covers the outer surface of the heart.
2. Parietal pericardium - Lines the surface of the pericardial sac, which surrounds the heart.

Heart wall
The heart walls are composed of three layers:
1. Epicardium – Covers the outer surface of the heart
(squamous epithelial cells)
2. Myocardium – Forms most of the heart wall, this is the layer that contracts
3. Endocardium – Heart’s inner layer; bundles of smooth muscle

Chambers of the heart
- The heart has four hollow chambers.
- Two atria (singular: atrium); pump blood into the ventricles
-Two ventricles ; serve as the pumping chambers of the heart
Each lined with endocardium for smooth blood flow throughout the heart.

Heart valves
• The heart is equipped with four valves. The valves allow forward flow of blood through the heart and prevent backward flow
Pulmonary Valve
Aortic Valve Bicuspid (mitral) Valve
Tricuspid Valve from the atria through the ventricles out the great arteries leaving the heart.

Bicuspid and Tricuspid Valves (AV valves)
Bicuspid or Mitral valve (left AV valve)
- Consists of two flaps of endocardium
Tricuspid Valve
-Is the right AV valve
-Has three flaps

Semilunar valves
Between the ventricle & an artery
1. Pulmonic
2. Aortic
Each set of valves operates at a different time.
1. The AV valves are open during heart relaxation and closed when the ventricles are contracting.
2. The semilunar valves are closed during heart relaxation and are forced open when the ventricles contract.
http://video.about.com/heartdisease/How-the-Valves-Work.htm

Posterior View

Blood Vessels (Tubes)
The three major types of vessels are arteries, capillaries, and veins:
1. Arteries carry blood away from the heart
2. Veins carry blood toward the heart
3. Capillaries are the smallest blood vessels. They carry blood to and from all the small places in the body.
** Arterioles and venules are also vessels

Circulatory System
• Blood flows through a network of blood vessels that extend between the heart and peripheral tissues
• The vascular system has 2 distinct circulations:
1. Pulmonary circulation – short loop that runs from the heart to the lungs and back to the heart.
2. Systemic circulation – routes blood through a long loop to all parts of the body and returns to the heart.
• Each circuit begins and ends at the heart, and

Systemic and Pulmonary Circulations
Pulmonary circuit
- from heart to lungs back to heart
Systemic circuit
- from heart to body back to heart http://www.mayoclinic.com/health/circulatory-system/MM00636