USI Summer Session Chapter 18 A&P - The Heart

16 terms by JustBrumley

Create a new folder

Advertisement Upgrade to remove ads

The Heart

size of a fist

In the mediastinum between second rib and fifth intercostal space
On the superior surface of diaphragm
Two-thirds to the left of the midsternal line
Anterior to the vertebral column, posterior to the sternum
Enclosed in pericardium, a double-walled sac

Pericardium

Protects, anchors, and prevents overfilling

Pericardium

Deep two-layered serous pericardium
Parietal layer lines the internal surface of the fibrous pericardium
Visceral layer (epicardium) on external surface of the heart
Separated by fluid-filled pericardial cavity (decreases friction)

Epicardium

visceral layer of the serous pericardium

Myocardium

Spiral bundles of cardiac muscle cells

Fibrous skeleton of the heart: crisscrossing, interlacing layer of connective tissue

Anchors cardiac muscle fibers
•Supports great vessels and valves
•Limits spread of action potentials to specific paths

Endocardium

continuous with endothelial lining of blood vessels

Atria

Separated internally by the interatrial septum

Coronary sulcus (atrioventricular groove) encircles the junction of the atria and ventricles

Auricles increase atrial volume

Ventricles

Separated by the interventricular septum

Anterior and posterior interventricular sulci mark the position of the septum externally

Atria: The Receiving Chambers

Walls are ridged by pectinate muscles

Vessels entering right atrium

Superior vena cava

Inferior vena cava

Coronary sinus

Vessels entering left atrium

Right and left pulmonary veins

Ventricles: The Discharging Chambers

Walls are ridged by trabeculae carneae

Papillary muscles project into the ventricular cavities

Coronary Circulation

The functional blood supply to the heart muscle itself

Arterial supply varies considerably and contains many anastomoses (junctions) among branches

Collateral routes provide additional routes for blood delivery

Coronary Circulation: Arteries

Right and left coronary (in atrioventricular groove), marginal, circumflex, and anterior interventricular arteries

Coronary Circulation: Veins

Small cardiac, middle, and great cardiac veins

Coronary sinus

Homeostatic Imbalances

Angina pectoris

Myocardial infarction (heart attack)

Angina pectoris

Thoracic pain caused by a fleeting deficiency in blood delivery to the myocardium

Myocardial infarction

(heart attack)

Prolonged coronary blockage

Areas of cell death are repaired with noncontractile scar tissue

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set