Biology 1203: Heart and Blood: week 2

What is the directional orientation of the base of the heart?

It is directed posteriorly, superiorly, and to the right.

The inferior surface of the heart rests on what structure?

The diaphragm.

The heart is located _ to the lungs.

medial

The protective membrane surrounding the heart is called the _.

pericardium

From superficial to deep, what are the three main layers of the heart wall?

Epicardium, myocardium, and endocardium.

What are the two layers of the pericardium?

The fibrous pericardium and the serous pericardium.

The serous pericardium is divided into which two layers?

The parietal pericardium and the epicardium (visceral pericardium).

What is the name of the fluid-filled space between the layers of the serous pericardium?

The pericardial cavity.

The epicardium is also known as the _ layer.

visceral

What is the myocardium?

The muscular tissue layer of the heart responsible for contraction.

What is the endocardium?

The thin inner lining of the heart chambers.

Which side of the heart pumps blood to the lungs?

The right side of the heart.

Which side of the heart pumps blood to the rest of the body?

The left side of the heart.

What is the function of the right atrium?

Receives deoxygenated blood from the body.

What is the function of the right ventricle?

Pumps deoxygenated blood to the lungs.

What is the function of the left atrium?

Receives oxygenated blood from the lungs.

What is the function of the left ventricle?

Pumps oxygenated blood to the body.

What blood vessels return blood from the body to the heart?

The superior and inferior vena cava.

What blood vessels return blood from the lungs to the heart?

The pulmonary veins.

What blood vessel carries blood from the heart to the lungs?

The pulmonary trunk (pulmonary arteries).

What blood vessel carries blood from the heart to the body?

The aorta.

What structure separates the right and left sides of the heart?

The septum.

What is the name of the valve between the right atrium and right ventricle?

The tricuspid valve.

What is the name of the valve between the left atrium and left ventricle?

The bicuspid (mitral) valve.

What is the function of atrioventricular (AV) valves?

Prevent backflow of blood into the atria during ventricular contraction.

What are the two semilunar valves?

The pulmonary semilunar valve and the aortic semilunar valve.

What is the function of the semilunar valves?

Prevent backflow of blood into the ventricles.

What structures anchor the AV valves to prevent them from flipping backward?

The chordae tendineae.

What muscles attach to the chordae tendineae?

Papillary muscles.

What is the purpose of papillary muscles?

Prevent valve prolapse during ventricular contraction.

What is the coronary circulation?

The blood supply to the heart muscle itself.

What arteries supply blood to the heart muscle?

The coronary arteries.

Where do the coronary arteries branch from?

The base of the aorta.

What veins drain blood from the heart muscle?

The cardiac veins.

Where does blood from the cardiac veins drain?

Into the coronary sinus.

Where does the coronary sinus empty?

Into the right atrium.

What is the sinoatrial (SA) node?

The heart’s natural pacemaker.

Where is the SA node located?

In the right atrium.

What is the atrioventricular (AV) node?

A conduction center that delays the electrical impulse before it enters the ventricles.

Where is the AV node located?

In the inferior portion of the right atrium.

What structure carries impulses from the AV node into the interventricular septum?

The AV bundle (bundle of His).

What are the right and left bundle branches?

Pathways that carry impulses down the interventricular septum.

What are Purkinje fibers?

Conduction fibers that distribute the impulse through the ventricular myocardium.

What is systole?

The phase of the cardiac cycle when the heart contracts.

What is diastole?

The phase of the cardiac cycle when the heart relaxes.

What is cardiac output?

The volume of blood pumped by each ventricle per minute.

What is heart rate?

The number of heartbeats per minute.

What is stroke volume?

The amount of blood pumped by one ventricle in a single contraction.

What is blood pressure?

The force of blood against arterial walls.

What is systolic pressure?

Arterial pressure during ventricular contraction.

What is diastolic pressure?

Arterial pressure during ventricular relaxation.

What is the function of red blood cells?

Transport oxygen.

What is the function of white blood cells?

Defend the body against pathogens.

What is the function of platelets?

Help with blood clotting.

What is plasma?

The liquid portion of blood.

What is hematocrit?

The percentage of blood volume occupied by red blood cells.

What is hemoglobin?

The oxygen-carrying protein in red blood cells.

What is anemia?

A condition of reduced red blood cells or hemoglobin.

What is leukemia?

Cancer of white blood cells.

What is thrombosis?

Formation of a blood clot within a blood vessel.

What is embolism?

Movement of a blood clot to another location in the body.

What is atherosclerosis?

Buildup of fatty deposits in arterial walls.

What is a myocardial infarction?

Heart attack caused by blockage of coronary blood flow.

What is the systemic loop?

A system of systemic capillaries that are responsible for moving low oxygen blood