EKG 205 QUIZ 1

How much blood does the heart pump in 24 hours?

Between 7,000 to 8,640 per day

Epicardium

outermost layer; contains coronary arteries

Myocardium

middle, thickest layer; made of muscle

Endocardium

Thin, innermost layer; forms heart valves

Pericardium

Double walled sac that encloses the heart

atrial kick

Atria contracts, squeezing remainder of blood into ventricles

absolute refractory

NO stimulus can cause depolarization

Relative Refractory

Strong stimulus can cause depolarization

Supernormal refractory period

Weak stimulus can cause depolarization

action potential

Phase 4 (cell is at rest), Phase 0 (cell is stimulated/ depolarized), Phase 1 and 2 (early repolarization, calcium is released), Phase 3 (rapid repolarization, sodium and potassium return to their normal places)

Role of pulmonary veins

return oxygenated blood from lungs to left atrium

Where is deoxygenated blood normally found in the heart

right side

what does an EKG illustrate

electrical activity of the heart

cardiac cycle

mechanical events that occur to pump blood

diastole

ventricles relax and fill with blood

systole

ventricles contract and expel

automaticity

ability to create an impulse without outside stimulation

conductivity

ability to conduct an impulse to neighboring cells

excitability

ability to depolarize

contractility

ability to contract

what hormone does sympathetic nervous system secrete

norepinephrine

what hormone does the parasympathetic nervous system secrete

acetylcholine