Nursing Anatomy and Physiology Final Exam Review (exam 4, spring 2017)
what is the sequence of events in the transmission of an impulse through the heart muscle
1. SA node 2. through the atria 3. AV node 4. AV bundle 5. bundle branches 6. purkinje fibers 7. through the ventricles
sinusoids are found in:
1. bone marrow 2. spleen
sympathetic observation of the heart:
1. increases the heart rate 2. increases the force if contractions
which leukocytes are granulocytes
1. neutrophils 2. eosinophils 3. basophils
which can be used to characterize blood flow in the human body
1. there is a unidirectional blood flow 2. arteries carry blood away from the heart (a= away) 3. veins carry blood toward the heart
during a cardiac cycle, how many of the four chambers contract at any one time:
2
which segment of the ECG reflects the plateau of ventricular muscle cells' action potentials:
S-T segment
an autorhythmic heart cell is one in which (auto= spontaneous)
action potentials fire spontaneously (auto= spontaneous)
just prior to atrial contraction:
all four chambers are at rest and AV valves are open
the plateau phase of an action potential:
allow cardiac muscle cells to contract and then relax without locking up
which of the following would cause a decrease in cardiac output
an increase in afterload
norepinephrine is considered a positive chronotropic agent because it causes
an increase in the firing rate of SA node cells
which valve prevents the backflow of blood onto the left ventricle when the ventricles relax:
aortic semilunar valve
according to the Frank -Starling law:
as the volume of blood entering the heart increases, ventricular contractions become more forceful
in an ECG, the P wave is generated when the:
atria depolarize
which type of leukocyte releases histamine:
basophil
cardiac output is the amount of blood that is pumped:
by a single ventricle in one minute
once an SA nodal cell reaches threshold, the depolarization phase occurs during which?
calcium come in through fast voltage-gates channels
gas, nutrient, and waste exchange occur between the _______ and the tissues of the body:
capillaries
valves in veins:
cause venous blood flow to go in only one direction
which is the most common type of capillary:
continuous
which action leads to the closure of the right atrioventricular(AV) valve:
contraction of the right ventricle
vagal tone refers to the:
decreasing of the heart rate below its inherent rhythm by parasympathetic stimulation
the main function of leukocytes is to:
defend against pathogens
during the plateau phase of a cardiac muscle cell's action potential, the membrane stays:
depolarized as potassium exits and calcium enters
oxygen and carbon dioxide are transported between the blood and interstitial fluid by way of:
diffusion from areas of higher concentration to lower concentration
the largest arteries of the body are classified as:
elastic arteries
the membrane of a contractile cardiac muscle cell contains:
fast voltage-gated sodium channels and close voltage-gated calcium channels
as a venous pathway moves closer to the heart, the veins:
get larger
cardiac output equals the:
heart rate multiplied by stroke volume
occlusion of blood vessels tends to lead to:
inadequate blood supply and damage to body tissues
the shutting of the semilunar valves occurs during which phase:
isovolumetric diastole
blood moves into and then out of a heart chamber because:
it moves along its pressure gradient, and that gradient depends on contraction and relaxation during the cardiac cycle
cardiac output is usually expressed in:
liters per minute
the type of leukocyte that will migrate in the blood and: take up residence in the tissues as a macrophage is a(n)
monocyte
the layer of the heart wall composed of the cardiac muscle tissue is the (cardiac=heart, m(yo)=muscle)
myocardium (cardiac= heart, m(yo)=muscle)
A drug that decreased calcium levels in a muscle cell and thereby lowered the number of crossbridges formed during the hearts contractions would be a:
negative inotropic agent
which are the most numerous of the leukocytes
neutrophils
the heart valves:
permit the passage of blood in one direction
which carries oxygenated blood from the lungs to the heart:
pulmonary veins
in an ECG, what does the T wave represent:
repolarization of the ventricles
which heart chambers contain deoxygenated blood
right atrium and right ventricle
someone with tachyarrhythmia would be expected to show an abnormally:
small Q-T interval
which circuit of the cardiovascular system is responsible for sending blood to the kidneys, stomach and pelvic regions:
systemic circuit (s=systems)
which part of the circulatory system holds the largest amount of blood:
systemic veins
during ventricular contraction:
the semilunar valves open and the AV valves close
the ______ is composed of an endothelium and a subendothelial layer made up of a thin layer of areolar connective tissue
tunica intima (inti= internal)
the _____ is composed of circularly arranged layers of smooth muscle cells
tunica media (med= middle)
A network of small arteries called the _______ provides a blood supply to the tunica externa (exter=outside) of very large vessels
vasa vasorum
the term "epicardium" is another name for:
visceral layer of the serosal pericardium