The Heart: Structure and Function

Flashcards covering heart anatomy, physiology, the circulation path, and common cardiac conditions based on lecture transcripts.

Daily Heart Beat Frequency

The heart beats $100,000$ times every day.

Blood Pumping Volume per Minute

The volume of blood the heart pumps every minute is $1.5 \text{ gallons}$.

Normal Heart Valve Size

A normal heart valve is approximately the size of a half dollar coin.

Grey Whale Heart

The largest heart ever recorded belonged to this animal.

Standard Heart Size

On average, a person's heart is about the size of their clenched fist.

Atria

The upper two chambers of the heart that receive and collect blood.

Ventricles

The lower two chambers of the heart that pump blood out of the heart.

Septum (or Seplum)

The muscle that divides the heart into right and left halves.

Heart Valves (Purpose)

To prevent backflow of blood and ensure blood flows in one direction.

Tricuspid Valve

The valve through which blood passes when moving from the right atrium to the right ventricle.

Pulmonary Semilunar Valve

The valve blood passes through as it leaves the right ventricle to enter the pulmonary arteries.

Mitral (Biscuspid) Valve

The valve that blood flows through to move from the left atrium into the left ventricle.

Aortic Semilunar Valve

The valve blood passes through as it exits the left ventricle to enter the aorta.

Superior and Inferior Vena Cava

The large veins that carry deoxygenated blood from the upper and lower body to empty it into the right atrium.

Pulmonary Arteries

Vessels that take blood from the heart to the lungs so gas exchange can occur.

Pulmonary Veins

The vessels that bring oxygenated blood back from the lungs to the left atrium of the heart.

Aorta

The main artery that carries blood from the left ventricle to be pumped to the rest of the body.

Pulmonary Circuit

The movement of blood specifically from the heart to the lungs and back to the heart.

Systemic Circulation

The movement of blood specifically from the body to the heart and back to the body.

Systole

The phase of the cardiac cycle where the heart muscle contracts; includes Atrial and Ventricular subtypes.

Diastole

The phase of the cardiac cycle when the atria and ventricles relax and start to fill with blood.

Myogenic Control

The characteristic where the heart continues to beat based on an electrical signal from within the heart muscle itself.

Sinoatrial (SA) Node

Also known as the pacemaker, it starts the electrical signal as blood fills the right atrium and sets the heart's pace.

Atrioventricular (AV) Node

The part of the electrical system where impulses pause for $0.1 \text{ s}$ as blood fills the ventricles.

Bundle of His and Purkinje Fibers

Components of the cardiac conduction system that move signals along the walls of the ventricles to cause them to contract.

Congestive Heart Failure

A condition where the heart is too weak or stiff to pump blood effectively.

Myocardial Infarction

A heart attack caused by a blocked coronary artery, resulting in a lack of oxygen and the death of heart muscle.

Atrial Fibrillation

A condition characterized by abnormal electrical impulses in the atrium causing an irregular heart beat.