Heart Anatomy and Functions

Flashcards covering key vocabulary related to the anatomy and functions of the heart.

Heart rate

Average of 75 beats per minute.

Cardiac output

The amount of blood the heart pumps per minute, approximately 5.25 L/min.

Pericardium

A double-walled sac that contains the heart and helps prevent undesired movement.

Epicardium

Visceral layer of serous pericardium, simple squamous epi

Atria

Upper chambers of the heart that receive blood.

Ventricles

Lower chambers of the heart that pump blood out of the heart.

Pulmonary circuit

Carries blood from the right ventricle to the lungs and back.

Systemic circuit

Transports oxygen-rich blood from the left ventricle to the rest of the body.

Chordae tendineae

Fibrous cords that anchor the heart valves and prevent them from everting.

Intercalated discs

Structures that connect cardiac muscle cells, containing gap junctions and desmosomes.

Sinoatrial node

The pacemaker of the heart that regulates heart rate.

Coronary circulation

The flow of blood to the tissues of the heart. Inadequate circulation causes heart attack

Heart failure

A condition in which the heart becomes unable to pump enough blood to meet the body's needs.Weakened ventricles fail to empty completely and become overfilled, causing a backup/edema (congestion) in tissues outside pulmonary or systemic circuits

Myocardium

cardiac muscle, bulk of the heart wall

Endocardium

lines chambers and covers valves, simple squamous epi, called “endothelium”

Heart valves

composed of dense connective tissue, 2 or 3 cusps. permit passage of blood in one direction and prevent backflow

Fibrous skeleton of heart

Dense connective tissue located between atria and ventricles. Anchors heart valves and is framework for cardiac muscle movement

Conduction system of heart

The conduction system of the heart is a pathway of specialized cardiac muscle cells that generate and conduct electrical impulses, regulating the heartbeat and coordinating contraction.

Cardiac plexus and the parasympathetic NS

The cardiac plexus is a network of nerve fibers and ganglia located near the heart that regulates heart function. It interacts with the parasympathetic nervous system to control heart rate and maintain homeostasis.

Cardiac plexus and sympathetic NS

The cardiac plexus also interacts with the sympathetic nervous system, which increases heart rate and contractility during stress or exercise, contributing to the body’s fight or flight response.