PHA 538 Lab 12: Heart Anatomy Flashcards

Vocabulary flashcards covering the anatomy, layers, vessels, and conduction system of the heart based on Lab 12 materials.

Pericardium

A double layer sac surrounding the heart composed of a fibrous and a serous pericardial membrane.

Fibrous pericardium

The outermost layer of the pericardium made of tough, dense irregular connective tissue; it protects the heart, prevents overfilling, and anchors it to the diaphragm.

Serous pericardium

A thin double-layered membrane deep to the fibrous pericardium composed of a parietal layer and a visceral layer.

Parietal layer of serous pericardium

The simple squamous epithelium that lines the internal surface of the fibrous pericardium.

Parietal layer of serous pericardium

The simple squamous epithelium that lines the internal surface of the fibrous pericardium.

Pericardial cavity

contains serous fluid to reduce friction during heart contractions.

Pericardial cavity

contains serous fluid to reduce friction during heart contractions.

Epicardium

The outermost layer, consisting mostly of mesothelium and adipose tissue; it contains blood vessels and nerves.

Endocardium

The innermost layer, composed of simple cuboidal epithelium and loose connective tissue; it lines the chambers, valves, and base of great vessels.

Apex

The inferior tip of the left ventricle located posterior to the $5^{th}$ intercostal space; it is the site for auscultation of the bicuspid valve closure.

Right atrium

receives deoxygenated blood from the superior and inferior vena cavae, the coronary sinus, and anterior cardiac veins.

Right auricle

increases its volume capacity during excessive venous return.

Pectinate muscles

increase atrial contraction force without increasing muscle mass.

Left atrium

receives oxygenated blood from the lungs via pulmonary veins.

Right ventricle

receives deoxygenated blood from the right atrium and pumps it to the lungs via the pulmonary trunk.

Papillary muscles

prevent valve inversion.

Chordae tendineae

prevent valve prolapse into the atria during ventricular systole.

Septomarginal trabeculae (moderator band)

it reinforces the wall and assists conduction.

Interatrial septum

divides the right and left atria to prevent the mixing of blood.

Interventricular septum

divides the right and left ventricles.

Right atrioventricular (tricuspid) valve

prevents backflow of blood.

Left atrioventricular (mitral / bicuspid) valve

prevents backflow during ventricular contraction.

Pulmonary semilunar valves

prevent blood backflow into the ventricle.

Aortic semilunar valve

prevent blood from flowing back into the ventricle.

Superior vena cava (SVC)

collects deoxygenated blood and drains it into the right atrium.

Inferior vena cava

collects deoxygenated blood from the body below the diaphragm and drains it into the right atrium.

Pulmonary trunk

carry deoxygenated blood to the lungs.

Pulmonary veins

carry oxygenated blood from the lungs to the posterior wall of the left atrium.

Aorta

carries oxygenated blood to the systemic circulation.

Coronary sinus

receives venous drainage from the great, middle, and small cardiac veins and drains into the right atrium.

Sinoatrial (SA) node

The pacemaker of the heart located in the posterior wall of the right atrium; it initiates the normal contractile rhythm.

Atrioventricular (AV) node

Conducting cells in the floor of the right atrium that transmit and slightly delay electrical impulses to allow the atria to empty before ventricular contraction.

Atrioventricular (AV) bundle

Conducting cells in the interventricular septum that receive impulses from the AV node and transmit them to the bundle branches.

Purkinje fibers

Conductive fibers that spread electrical impulses from the apex toward the atria within the ventricular walls.

Cardiac plexus

A network of nerves receiving axons from the Vagus nerves and sympathetic trunk that influences heart rate and contraction force.

Vagus nerve (CN X)

Provides parasympathetic axons to the heart to reduce heart rate, decrease contraction force, and cause vasoconstriction of coronary arteries.

Cardiac nerves

Postganglionic sympathetic fibers that increase heart rate, increase contraction force, and cause vasodilation of the coronary arteries.