Cardiovascular Structure and Function

What are the major components of the CVS?

Heart (the pump) and vessels (the piping)

What is the heart made of?

Living and non-living extracellular material called connective tissue

What kind of a pump is the heart?

Variable output

What is the purpose of the CVS?

Delivering resources and removing wastes

Where is oxygen taken?

From the lungs to all cells

Where are nutrients and water taken?

From the intestinal tract to all cells

Where are stored energy reserves taken?

From liver and adipose cels to all cells

Where are hormones taken?

From endocrine cells to target cells

Where are metabolic wastes removed?

From all cells to the kidneys

Where is heat removed?

From all cells to skin

Where is carbon dioxide removed?

From all cells to the lungs

What is the medium for the CVS?

Water

What are the two circulatory loops?

Pulmonary loop and systemic loop

What does the pulmonary loop do?

Goes to the lungs, carrying oxygen-depleted blood laden with carbon dioxide

Where does the pumping energy for the pulmonary loop come from?

Right Heart

What does the systemic loop do?

Goes through the body carrying blood charged with oxygen and nutrients to the body tissues

How is blood flow driven through the systemic loop?

Left Heart

What are the two chambers in the right and left heart?

Atrium (receives blood) and ventricle (pumps blood)

What are the 3 functional areas of circulatory loops?

Arterial vessels, capillaries, and venous vessels

Alveoli:

Surrounded by capillaries to create a site for gas exchange

What does gas exchange follow at alveolar sacs?

The concentration gradient (O2 in, CO2 out)

What keeps alveoli open?

Surfactant (reduces surface tension)

What are the atria?

Low-pressure pumps that “top off” ventricles with additional blood

What are the ventricles?

High-pressure pumps that provide the motive force for blood flow through the circulatory loops

How much does atrial contraction fill the ventricle?

25%

Where does the right atrium receive blood from?

Vena cavae

Where does the left atrium receive blood from?

Pulmonary vein

What are the valves in the heart?

Atrioventricular valves (tricuspid and mitral) and semilunar valves (pulmonary and aortic)

What is the tricuspid valve?

The right AV valve

What is the mitral (bicuspid) valve?

The left AV valve

What is the pulmonary valve?

The valve at the entrance of the pulmonary artery

What is the aortic valve?

The valve at the entrance of the aorta

What do AV valves do?

Prevent backflow from ventricles to atria

What keeps valves from inverting into atria?

Chordae tendineae and papillary muscles

Why does the mitral valve experience problems more commonly than the tricuspid valve?

The left ventricle experiences higher pressures

What are chordae tendineae?

Tendon-like cords inside the heart

What do chordae tendineae do?

Connect the AV valves flaps to the papillary muscles in the ventricles; also maintain valve position during contraction