The Cardiovascular System

Question 1

Location of the Heart:

Answer 1

Position: Located within the mediastinum.
Extent: Extends obliquely about 5 inches from the second rib to the fifth intercostal space.
Orientation: Rests on the diaphragm, anterior to the vertebral column, and posterior to the sternum.
Distribution of Mass: Two-thirds of the heart mass lies left of the midsternal line.
Apex: Points downward toward the left hip.

Question 1

Function of the heart

Answer 1

Description: Muscular pump that propels blood through the lungs to the tissues.
Heart Disease: Results from disturbances in function.

Question 2

Heart Coverings:

Answer 2

Pericardium:
Description: Double-walled sac.
Outer Layer: Composed of tough connective tissue.
Epicardium:
Description: Visceral layer of the pericardium covering the myocardium.

Question 3

Layers of the Heart Wall:

Answer 3

Epicardium:
Description: Outer layer of connective tissue containing coronary arteries.
Myocardium:
Description: Middle layer, thickest layer, muscular; responsible for the heart’s pumping action.
Endocardium:
Description: Innermost layer, smooth membrane; heart valves are part of the endocardium.

Question 4

Chambers of the Heart:

Answer 4

Right Half:
Components: Right atrium (RA) and right ventricle (RV).
Function: Acts as the pulmonary pump, circulating blood into the pulmonary artery and lungs.
Left Half:
Components: Left atrium (LA) and left ventricle (LV).
Function: Acts as the systemic pump, circulating blood into the aorta, organs, and tissues.

Question 5

Main Blood Supply:

Answer 5

Description: Shortest circulation in the body.
Reasoning: Myocardium is too thick for nutrient diffusion

Question 6

Arterial Supply:

Answer 6

Origin: Aorta branches into right and left coronary arteries.
Pathway: Arterial blood is carried to the heart.