AP II

What are the three components of the cardiovascular system?

Heart, blood vessels, and blood.

What are the three primary functions of the cardiovascular system?

Transportation, regulation, and protection.

What is the function of arteries?

Carry blood away from the heart.

What is the function of veins?

Carry blood toward the heart.

What is the function of capillaries?

Exchange gases, nutrients, wastes, and other substances between blood and tissues.

Where does pulmonary circulation begin and end, and what is its purpose?

Begins in the right ventricle, ends in the left atrium, and oxygenates blood.

Where does systemic circulation begin and end, and what is its purpose?

Begins in the left ventricle, ends in the right atrium, and delivers oxygenated blood to the body.

Which circulation operates at lower pressure, and why?

Pulmonary circulation because the lungs are close to the heart and their capillaries are delicate.

Why are pulmonary arteries and pulmonary veins unique?

Pulmonary arteries carry deoxygenated blood; pulmonary veins carry oxygenated blood.

Where is the heart located, and where do the apex and base point?

The heart is in the middle mediastinum. The apex points left, inferior, and anterior; the base points posterior.

What structures are found in the mediastinum?

Heart, great vessels, trachea, esophagus, thymus, lymphatic structures, nerves, and connective tissue.

What are the four functions of the pericardium?

Protects the heart, anchors it, prevents overfilling, and reduces friction.

List the layers superficial → deep.

Fibrous pericardium → Parietal serous pericardium → Pericardial cavity → Visceral serous pericardium (Epicardium) → Myocardium → Endocardium.

List the layers deep → superficial.

Endocardium → Myocardium → Epicardium → Pericardial cavity → Parietal serous pericardium → Fibrous pericardium.

What is the fibrous pericardium, and what is its function?

The tough outer connective tissue layer that anchors the heart and prevents overstretching.

What is the parietal serous pericardium?

The serous membrane lining the inside of the fibrous pericardium.

What is the visceral serous pericardium, and what is another name for it?

The serous membrane covering the heart; also called the epicardium.

What is found in the pericardial cavity, and what is its function?

A thin film of serous fluid that reduces friction during heart contractions.

Which three layers make up the heart wall?

Epicardium, Myocardium, and Endocardium.

Which layer forms most of the heart wall, and why is the left ventricle thicker?

The myocardium; the left ventricle generates higher pressure for systemic circulation.

What is the function of the endocardium?

Lines the chambers and valves and is continuous with blood vessel endothelium.

What is cardiac tamponade?

Fluid accumulation in the pericardial cavity that decreases ventricular filling, stroke volume, and cardiac output.

A myocardial infarction damages which layer of the heart?

Myocardium.

Describe the four chambers of the heart and their functions.

Right atrium: receives deoxygenated blood. Right ventricle: pumps deoxygenated blood to the lungs. Left atrium: receives oxygenated blood. Left ventricle: pumps oxygenated blood to the body.

What is the difference between an atrium and an auricle?

The atrium is the chamber; the auricle is an ear-like pouch that increases atrial capacity.

Where is the tricuspid valve located, and how many cusps does it have?

Between the right atrium and right ventricle; 3 cusps.

Where is the mitral (bicuspid) valve located, and how many cusps does it have?

Between the left atrium and left ventricle; 2 cusps.

Where is the pulmonary semilunar valve located, and how many cusps does it have?

Between the right ventricle and the pulmonary trunk; 3 cusps.

Where is the aortic semilunar valve located, and how many cusps does it have?

Between the left ventricle and the aorta; 3 cusps.

Describe the major great vessels of the heart.

Superior vena cava: returns blood from upper body. Inferior vena cava: returns blood from lower body. Pulmonary trunk: carries blood from the right ventricle. Pulmonary veins: return oxygenated blood to the left atrium. Aorta: carries oxygenated blood from the left ventricle. Coronary sinus: returns blood from the myocardium to the right atrium.

Trace blood flow through the heart.

Body → Superior/Inferior Vena Cava → Right Atrium → Tricuspid Valve → Right Ventricle → Pulmonary Semilunar Valve → Pulmonary Trunk → Pulmonary Arteries → Lungs → Pulmonary Veins → Left Atrium → Mitral Valve → Left Ventricle → Aortic Semilunar Valve → Aorta → Body.