Chapter 18: The Heart Review

right side

side that receives oxygen-poor blood from body tissues and then pumps this blood to lungs to pick up oxygen and dispel carbon dioxide

pulmonary circuit

blood vessels that carry blood to and from lungs form the ___

left side

side that receives oxygenated blood returning from lungs and pumps this blood throughout body to supply oxygen and nutrients to body tissues

systemic circuit

blood vessels that carry blood to and from all body tissues form the ___

right atrium

receives blood returning from the systemic circuit

left atrium

receives blood returning from the pulmonary circuit

right ventricle

pumps blood into the pulmonary circuit

left ventricle

pumps blood into the systemic circuit

myocardium

layer of the heart wall composed of cardaic muscle

coronary sulcus

encircles the junction of atria and ventricles like a crown

coronary sinus

collects blood draining from the myocardium

pulmonary veins

deliver oxygenated blood from the respiratory zones of the lungs to the heart

aorta

major systemic artery; arises from left ventricle of heart

largest artery in body

fibrous pericardium

the most superficial covering of the heart

atrioventricular (AV) Valves

prevents backflow into the atrium when the connected ventricle is contracting

tricuspid valve

right AV valve

bicuspid (mitral) valve

left AV valve

chordae tendineae

tiny white collage cords

anchors cusps to the papillary muscles protruding from the ventricular walls

semilunar (SL) valves

prevent backflow into the associated ventricles

arteries

transport oxygen-rcih blood from heart

veins

transport oxygen-poor blood to heart

coronary circulation

the functional blood supply of the heart; shortest circulation in the body

circumflex artery

supplies the left atrium and the posterior walls of the left ventricles

circumflex artery

what coronary vessel supplies oxyge-rich blood to left atrium and posterior walls of left ventricle

intrinsic cardiac conduction system

consists of noncontractile cardiac cells specialized to initiate and distribute impulses throughout the heart

pacemaker cells

special ability to depolarize spontaneously and so pace the heart

arrhythmias

irregular heart rhythm, often caused by defects in the intrinsic conduction system

fibrillation

condition of rapid and irregular or out-of-phase heart contractions

ECG

graphic record of the electrical activity of the heart

P wave

atria depolarization

QRS Complex

results from ventricular depolarization and precedes ventricular contraction

T wave

ventricular repolarization

P-R Interval

beginning of atrial excitation to beginning of ventricular excitation

S-T segment

plateau phases

beginning of ventricular depolarization through ventricular repolarization

sinoatrial (SA) node

Which component of the conduction system sets the pace for the heart as a whole?

systole

period when either the ventricles or atria are contracting

diastole

relaxation

heart murmurs

abornaml heart sound (usually from valve problems)

semilunar valves open

what happens when ventricular pressure exceeds the aortic pressure?

cardiac output

amount of blood pumped out of ventricle in one minute

stroke volume

amount of blood pumped out of a ventricle during one contraction

cardiac reserve

difference between resting and maximal cardiac output

preload

degree to which cardiac muscle cells are stretched just before they contract

controls stroke volume

Frank-Starling law

positive relationship between preload and stroke volume

venous return

amount of blood returning to heart and distending its ventricles

afterload

pressure that ventricles must overcome to eject blood

tachycardia

a heart rate over 100 beats per minute

bradycardia

a heart rate below 60 beats per minute

pulmonary edema

leakage of fluid into air sacs and tissue of lungs

end systolic volume

volume of blood remaining in a ventricle after contraction