Human A & P Cardiovascular System
The superior mesenteric vein, which contains blood from the intestines, drains into the __________ which then carries blood to the liver.
hepatic portal vein,
Systolic pressure is the
highest pressure in the arteries, which occurs during contraction of the heart
The right atrium receives blood from the
inferior and superior venae cavae
Cardiac pain is due to
interruption of blood supply to cardiac muscle
Purkinje fibers are located in the
interventricular septum and ventriclesbetween the right atrium and right ventricle
The middle layer of the walls of veins differs from arteries in that
it contains less smooth muscle
The valve between the 2 chambers of the left side of the heart is the
mitral (bicuspid valve)
The thickest layer of the wall of the heart is the
myocardium
Plasma proteins help retain water in the blood by maintaining
osmotic pressure
The amount of blood that flows into capillaries is regulated by
precapillary sphincters
Which of the following vessels carries oxygen-rich blood?
pulmonary veins
Most of the blood enters the __________ during atrial relaxation.
ventricles
a decrease in arteriole diameter
will cause blood pressure to increase
Which vessel supplies blood to the liver, stomach and spleen?
celiac artery
The two major heart sounds are a result of
closing of heart valves
AV node (atrioventricular node)
connection btwn the atrium and ventricle
Blood is supplied to the myocardium by the _________, the first branches of the aorta.
coronary arteries
Blood is supplied to the myocardium by the __________ the first branches of the aorta.
coronary arteries,
The skeleton of the heart is composed of which provides sites of attachment for heart valves and muscle fibers.
dense connective tissue,
The visceral pericardium is also known as the
epicardium
nutrient and gas exchange occur in
capillary beds
how many pulmonary veins are there?
4
In the heart conduction system, action potentials move slowly through
AV Node
_____________ is embedded within the QRS complex and is not seen as a separate wave on the ECG.
Atrial repolarization
Atrial repolarization is embedded within the
QRS complex.
the sequence of travel by an action potential through the heart
SA Node, AV Node, AV bundle, bundle branches, purkinje fibers
Ventricular repolarization is represented by the
T wave
A mass of merging cells that act as a unit, 2 of which are found in the heart, is called
a functional syncytium
the left carotid and left subclavian arteries branch directly from the
aorta
the left ventricular contraction propels blood through the
aortic valve
order of vessels leaving and then returning to the heart
arteries, arterioles, capillaries, venules, veins
The P wave on an ECG represents
atrial depolarization
The uppermost or most superior part of the heart is the
base
The tricuspid valve is located
between the right atrium and right ventricle
describe the events of the cardiac cycle?
both atria contract while both ventricles relax; then both ventricles contract while both atria relax.
The right and left ___________ veins merge to form the superior vena cava.
brachiocephalic
The papillary muscles prevent the cusps from _________
bulging back into the atria
Concentrations of which of the following electrolytes have direct effects on the myocardium?
calcium and potassium
The blood vessel that participates directly in the exchange of substances between body cells and the blood is the
capillary
Most of the blood enters the ventricles during atrial
relaxation
During the flow of blood through the body, blood from the lungs returns to the
right atrium
oxygen poor blood enters the
right atrium
The cells that initiate the stimulus for contraction of the heart muscle are located in the
sinoatrial node (SA Node)
The middle layer of arterial walls is composed of
smooth and elastic connective tissue
External cardiac defibrillators are used for
sudden cardiac arrest
In the heart, action potential originates in
the SA Node
SA Node (sinoatrial node)
the heart's natural pacemaker, keeps the natural rhythm of the heart