anatomy test 4
pleateu phase
Ca2+ channels influx slow ca2+ channels and open them up. causes the depolarization b/c there are less K+ channels
which of the following is/are physiological effect(s) of angiotensin II
Increased thirst, increased ADH release, vasoconstriction
Platelets are made when _______ "explodes" and release their contents into surrounding tissues?
Megakaryocytes
For the most of ventricular diastole, which valve(s) is/are open?
Mitral (bicuspid) valve
which of the following are granulocytes
Neutrophils and eosinophils
which component of the intrinsic conduction system passes through the outer ventricular wall of the heart, beginning at the apex?
Purkinje fibers
which of the following factors are important to the movement of blood through veins?
Skeletal muscle "milking" effects thoracic cavity pressure changes sympathetic venoconstriction
which statement best describes arteries?
all carry blood away from the heart
which of the following is not part of the intrinsic conduction system of the heart
atrioventricular (AV) valve
this specialized mechanoreceptor is located in the carotid sinuses and detects arterial wall stretch, signaling to the brain to decrease blood pressure.
baroreceptors
which of the following factors contribute to resistance in blood vessels?
blood viscosity, blood vessel diameter, blood vessel length
Skeletal and cardiac muscle share many similarities EXCEPT which of the following?
both contain intercalated discs
what is the Ca+ -sensistive protein in smooth muscle that initiates contraction?
calmodulin
Permitting the exchange of nutrients and gases between the blood and tissue cells is the primary function of ________.
capillaries
This form of hemoglobin is formed when CO2 binds to the globe's amino acids rather than the heme group
carbaminohemoglonin
when CO2 levels rise or O2 levels fall, _________ stimulate the brain stem to increase cardiac output
chemoreceptors
which of the following type of capillary are most common in the body?
continuous
the atria receive blood from which the following blood vessels
coronary sinus inferir vena cava
Na+ channels influx through fast voltage gated and Na+ channels open. Causes an inactivation of the phase which causes it to stop
depolarization
the innermost layer of the heart lines the heart chamber and is called the
endocardium
the hemoglobin molecule contain how many Fe2+ ions
four
The majority of the ______ component of hemoglobin is recycled by the liver and incorporated into bilirubin
heme
transferrin
in blood, iron is primarily transported via
With a patient that is administered an injection of erythropoietin (EPO) you would expect to see ________.
increased hematocrit
in the cardiac cycle, ventricular filling takes place in ________?
mid to late ventricular diastole
sympathetic nervous system
norepinephrine (noradrenaline) is released as a part of the _________ nervous system and it is used to increase heart rate, as well as contractility of cardiac muscle
This term refers to spontaneously changing memebrane potentials that initiate waves of depolarization that spread throughout the myocardium
pacemaker potentials
which of the following is NOT an example of a formed element of blood tissue?
plasma
This blood protein is essential to the eventual digestion of fibrin threads in a clot
plasmin
This plasma protein converts prothrombin into thrombin, continuing the coagulation cascade
prothrombin activator
when arterial pressure drops, ______ is released from the kidneys in order to convert angiotensinogen into angiotensin I
renin
Ca+ channels stop or inactivate while K+ voltage gated channels open, causing membrane potential to go back to normal
repolarization
_________ represents the difference between end systolic volume and end diastolic volume
stroke volume
which of the following factors is/are used in the calculation of cardiac output?
stroke volume and heart rate
if the length of the absolute refractory period in cardiac muscle cells was the same as it is for skeletal muscle cells, _________.
tetanic contractions might occur, which would stop the heart's pumping action
vasoconstiction
the narrowing of a blood vessel is known as
Monocytes
this blood cell class accounts for 3-8% of leukocytes. After exiting the bloodstream, they are classified as macrophages and serve as important phagocytes
Atrial natriuretic peptide (ANP)
this hormone causes the kidneys to decrease blood volume (and therefore, blood pressure) by allowing the excretion of NA+
When hematopoietic stem cells are exposed to _______, platelets ultimately develop.
thrombopoietin
which of the following ABO blood types is known as the "universal donor"?
type O
the overall "thickness" of blood is known as ____, and this factor increases resistance in the blood vessels
viscosity
which of the following substances is in highest abundance in blood plasma
water
coronary artery
which of the following vessels directly nourishes they myocardium?
