peripheral nervous system
a part of the nervous system made up of nerves that extend throughout the body
somatic nervous system
division of the peripheral nervous system that controls VOLUNTARY actions
autonomic nervous system
(breathing, heartbeat)
the part of the nervous sytem that controls body functions that are not consciously directed
sympathetic nervous system
(fight or flight response)
part of the nervous system that works to INCREASE the heart rate; can be associated with fear/threat (fight or flight response)
parasympathetic nervous system
(relax)
part of the autonomic nervous sytem that works to SLOW heart rate
epicardium
epi+cardi+um
the outermost layer of the heart; a thin layer of connective tissue and fat that protects the heart and also contains the blood vessels that supply oxygen and nutrients to the heart (coronary arteries)
myocardium
myo+cardi+um
the middle and thickest layer of the heart; made up of cells capable of continuous rhythmic contraction
endocardium
endo+cardi+um
the thin, innermost layer of the heart; forms a smooth, elastic surface that allows blood to flow without stopping or clotting
superior vena cava
one of the largest VEINS in the body; returns oxygen-depleted blood from the upper body to the heart
inferior vena cava
one of the largest VEINS in the body; returns oxygen-depleted blood from the lower body to the heart
aorta
the body’s largest ARTERY, which branches off into the body’s smaller arteries to distribute oxygen-rich blood
coronary arteries
the arteries that provide oxygen and nutrients to the tissues of the heart
septum
in cardiology, the wall dividing the right and left sides of the heart
atria/atrium
the upper 2 chambers of the heart
ventricles
the lower 2 chambers of the heart
systole
the phase in which the heart is at work, contracting and pushing blood out of the left ventricle
diastole
the phase when the heart relaxes or rests
tricuspid valve - atrioventricular valve
(tri)
the heart valve located between the right atrium and right ventricle
pulmonary valve - pulmonary semilunar valve
the heart valve located between the right ventricle and and the pulmonary artery
bicuspid valve - mitral valve
(bi)
the heart valve located between the left atrium and left ventricle
aortic valve - aortic semilunar valve
the heart valve located between the left ventricle and aorta
pulmonary circuit
the circulation of blood between the heart and the lungs
systemic circuit
the circulation of blood between the heart and the rest of the body (except the lungs)
exchange sites
places in the body where oxygen and substances needed by the cells are delivered and waste products removed
