HEART LECTURE

The semilunar valves prevent backflow of blood into the _____.

ventricles

Which vessel carries oxygenated blood?

pulmonary vein

Which structure anchors the chordae tendinae of the atrioventricular valves?

papillary muscle

Which layer of the heart wall is visceral pericardium?

epicardium

Which heart chamber has the thickest myocardium?

the left ventricle, because it pumps blood at a higher pressure

Irregular ridges of muscle called trabeculae carneae are located within the walls of the__________.

ventricle

Which vessels drain into the right atrium?

superior and inferior vena cava and the coronary sinus

Valves with narrowed openings, that occur when cusps have fused or become stiffened by calcium deposits, are considered__________.

stenotic

What is the function of the chordae tendineae and papillary muscles of the bicuspid and tricuspid valves?

preventing eversion of the valves into the atria

Blood moves from the left ventricle into what vessel?

ascending aorta

Blood leaving the right ventricle exits through the__________ valve.

pulmonary

Identify the vessel that returns most of the blood from the heart into the right atrium.

coronary sinus

The right and left coronary arteries __________.

supply blood to the heart muscle itself

The right coronary artery branches into which two arteries?

marginal artery and posterior interventricular artery

An atherosclerotic blockage in the circumflex artery would result in decreased (or lack of) blood flow to the __________.

left atrium and posterior part of the left ventricle

Double pump?

Pulmonary circuit

Systemic circuit

Layers of the pericardial sac

2 layers:

-Fibrous pericardium= strong layer of dense CT

-Serous Pericardium = 2layers; parietal and visceral

Systemic Circulation

-Circulation between HEART and ENTIRE BODY

-OXYGENATED blood pumped from HEART TO BODY

-DEOXYGENATED blood is RETURNED BACK TO HEART

Pulmonary Circulation

-Circulation between HEART and LUNGS

-OXYGENATED blood RETURNED back to HEART

-DEOXYGENATED blood pumped FROM HEART TO LUNGS

Functional syncytium

Cardiac muscle cells are electrically connected by gap junctions and thus the entire myocardium behaves as a single unit to contract

Pacemaker cells

-produce electricity in the body by rapidly changing their electrical charge from positive to negative and back again

-located in the right atrium

Coronary circulation

-part of the systemic circulatory system that supplies blood to and provides drainage from the tissues of the heart

Heart rate set by SA node

Rate altered by autonomic nerves