VANDERS HUMAN PHYSIOLOGY MECHANISM
OF BODY FUNCTION CONCEPT REVIEW
GUIDE 2026 BODY REGULATION AND
INTEGRATED FUNCTION
◉ Erythrocytes. Answer: red blood cells
◉ Formed Elements. Answer: cells and cell fragments
◉ Hematocrit. Answer: percentage of blood volume that is
erythrocytes (45% in men; 42% in women)
◉ Hemodynamics. Answer: the relationship among blood pressure,
blood flow, and the resistance to blood flow
◉ Hydrostatic Pressure. Answer: the pressure exerted by any fluid
◉ Leukocytes. Answer: white blood cells
◉ Microcirculation. Answer: arterioles, capillaries, and venules
,◉ Plasma. Answer: the extracellular matrix of blood cells; 55% of
the body's total blood volume
◉ Platelets. Answer: cell fragments; used for blood clotting
◉ Portal System. Answer: exceptions to the usual anatomical pattern
of blood flow for some organs such as the liver and the anterior
pituitary gland. Blood passes through two capillary beds, arranged
in a series and connected by veins, before returning to the heart.
◉ Resistance (R). Answer: how difficult it is for blood to flow
between two points at any given pressure difference; the measure of
friction that impedes flow
◉ Viscosity. Answer: one determinant of resistance; a function of the
friction between molecules of a flowing fluid; the greater the
friction, the greater the friction, the greater the viscosity
◉ Absolute Refractory Period. Answer: the inability of the heart to
generate tetanic contractions; the period during and following an AP
when an excitable membrane cannot be re-excited. Because of the
prolonged, depolarized plateau in the cardiac muscle AP, the
absolute refractory period of cardiac muscle lasts almost as long as
the contraction, and the muscle cannot be re-excited multiple times
during an ongoing contraction
,◉ Afterload. Answer: the arterial pressures against which the
ventricle pump
◉ Atrioventricular (AV) Node. Answer: the portion of the conducting
system that is the link between atrial depolarization and ventricular
depolarization; located at the base of the right atrium; the
propagation of action potentials through the AV node is relatively
slow allowing atrial contraction to be completed before ventricular
excitation occurs
◉ Atrioventricular (AV) Valve. Answer: located between the atrium
and ventricle in each half of the heart; one-way valves; permit blood
to flow from atrium to ventricle but not backwards. Responsible for
the "lub" sound.
◉ Aortic Valve. Answer: opening of the left ventricle into the aorta
("dup" sound)
◉ Automaticity. Answer: the capacity for spontaneous, rhythmic
self-excitation provided to the SA node by the pacemaker potential.
◉ Bicuspid Valve. Answer: the left AV valve
, ◉ Bundle Branches. Answer: the right and left branches that the
Bundle of His divides into; conducting fibers that separate at the
bottom (apex) of the heart and enter the walls of both ventricles
◉ Bundle of His. Answer: after the AV node has become excited, the
AP propagates down the interventricular septum via this pathway;
also called the atrioventricular bundle
◉ Cardiac Cycle. Answer: orderly process of depolarization triggers
this cycle of atrial and ventricular contractions and relaxations
◉ Cardiac Output (CO). Answer: the volume of blood each ventricle
pumps as a function of time (liters per minute); in a steady state, the
CO flowing through the systemic and pulmonary circuits is the same
◉ Conduction System. Answer: Approx. 1% of cardiac cells that do
not function in contraction but have specialized features that are
essential for normal heart excitation; cells of the heart that are in
electrical contact with the cardiac muscle cells via gap junctions
◉ Contractility. Answer: the strength of contraction at any given
end-diastolic volume
◉ Coronary Arteries. Answer: Arteries supplying the myocardium;
exit from behind the aortic valve cusps in the very first part of the
OF BODY FUNCTION CONCEPT REVIEW
GUIDE 2026 BODY REGULATION AND
INTEGRATED FUNCTION
◉ Erythrocytes. Answer: red blood cells
◉ Formed Elements. Answer: cells and cell fragments
◉ Hematocrit. Answer: percentage of blood volume that is
erythrocytes (45% in men; 42% in women)
◉ Hemodynamics. Answer: the relationship among blood pressure,
blood flow, and the resistance to blood flow
◉ Hydrostatic Pressure. Answer: the pressure exerted by any fluid
◉ Leukocytes. Answer: white blood cells
◉ Microcirculation. Answer: arterioles, capillaries, and venules
,◉ Plasma. Answer: the extracellular matrix of blood cells; 55% of
the body's total blood volume
◉ Platelets. Answer: cell fragments; used for blood clotting
◉ Portal System. Answer: exceptions to the usual anatomical pattern
of blood flow for some organs such as the liver and the anterior
pituitary gland. Blood passes through two capillary beds, arranged
in a series and connected by veins, before returning to the heart.
◉ Resistance (R). Answer: how difficult it is for blood to flow
between two points at any given pressure difference; the measure of
friction that impedes flow
◉ Viscosity. Answer: one determinant of resistance; a function of the
friction between molecules of a flowing fluid; the greater the
friction, the greater the friction, the greater the viscosity
◉ Absolute Refractory Period. Answer: the inability of the heart to
generate tetanic contractions; the period during and following an AP
when an excitable membrane cannot be re-excited. Because of the
prolonged, depolarized plateau in the cardiac muscle AP, the
absolute refractory period of cardiac muscle lasts almost as long as
the contraction, and the muscle cannot be re-excited multiple times
during an ongoing contraction
,◉ Afterload. Answer: the arterial pressures against which the
ventricle pump
◉ Atrioventricular (AV) Node. Answer: the portion of the conducting
system that is the link between atrial depolarization and ventricular
depolarization; located at the base of the right atrium; the
propagation of action potentials through the AV node is relatively
slow allowing atrial contraction to be completed before ventricular
excitation occurs
◉ Atrioventricular (AV) Valve. Answer: located between the atrium
and ventricle in each half of the heart; one-way valves; permit blood
to flow from atrium to ventricle but not backwards. Responsible for
the "lub" sound.
◉ Aortic Valve. Answer: opening of the left ventricle into the aorta
("dup" sound)
◉ Automaticity. Answer: the capacity for spontaneous, rhythmic
self-excitation provided to the SA node by the pacemaker potential.
◉ Bicuspid Valve. Answer: the left AV valve
, ◉ Bundle Branches. Answer: the right and left branches that the
Bundle of His divides into; conducting fibers that separate at the
bottom (apex) of the heart and enter the walls of both ventricles
◉ Bundle of His. Answer: after the AV node has become excited, the
AP propagates down the interventricular septum via this pathway;
also called the atrioventricular bundle
◉ Cardiac Cycle. Answer: orderly process of depolarization triggers
this cycle of atrial and ventricular contractions and relaxations
◉ Cardiac Output (CO). Answer: the volume of blood each ventricle
pumps as a function of time (liters per minute); in a steady state, the
CO flowing through the systemic and pulmonary circuits is the same
◉ Conduction System. Answer: Approx. 1% of cardiac cells that do
not function in contraction but have specialized features that are
essential for normal heart excitation; cells of the heart that are in
electrical contact with the cardiac muscle cells via gap junctions
◉ Contractility. Answer: the strength of contraction at any given
end-diastolic volume
◉ Coronary Arteries. Answer: Arteries supplying the myocardium;
exit from behind the aortic valve cusps in the very first part of the
