EXAM 1 Flashcards
Which channels account for the “plateau” observed in the ventricular (fast) cardiac muscle action potential?
voltage-gated slow (L-type) Ca+2 channels,
Which channels account for action potential depolarization in slow, autorhythmic cardiac fibers?
voltage-gated slow (L-type) Ca+2 channels,
An increase in ventricular contractile force due to Frank-Starling mechanisms would be termed an increase
preload
The adrenergic receptors that directly mediate increases in heart rate and contractility are classified as:
beta-1; β1,
Parasympathetic nervous system effects on heart rate are mediated by which SA node receptors?
muscarinic
What is the carotid sinus baroreceptor action potential (AP) response to an acute increase in blood pressure?
AP frequency increases
Even though vessel radius decreases, the cross-sectional area of a capillary bed increases, causing blood flow velocity to:
decrease
What is the most important force driving filtration at the arterial end of a capillary?
Blood hydrostatic pressure
The most important determinant of “long-term” regulation of blood pressure would be:
blood volume
During strenuous exercise, which parameter would change the most?
muscle blood flow
Which component is the most important contributor to blood viscosity?
albumin
Which state would not be associated with anemia?
polycythemia
An elevated band cell count would indicate overproduction of which cell type?
neutrophils
What is the primary function of thrombin?
converts fibrinogen to fibrin
The first clotting factor the intrinsic and extrinsic pathways have in common is:
factor X
What does not prevent the spontaneous formation of a clot
the presence of tissue thromboplasin`
An individual has type B, Rh- positive blood. The individual has ____ antigens and can produce anti-________ antibodies
B and D; A
What is the largest leukocyte that contains small cytoplasmic granules and typically a kidney- or horseshoe shaped nucleus
Monocyte
A normal hematocrit is _______ of total blood volume.
37% to 52%
What are the least abundant of the formed elements?
Basophils
The universal donor of RBC’s, but not necessarily plasma, is blood type_______
O, Rh- negative
What would happen if all of the hemoglobin contained within the RBC’s became free in the plasma
it would increase blood osmolarity
A person with type AB blood has _____ RBC antigens
A and B
a patient is diagnosed with Leukocytosis if they have more than ________ WBCs/ul
10,000
The cessation of bleeding is specifically called
hemostasis
Where does myeloid hemopoiesis take place in adults
Red bone marrow
Which cells aid the bodys defense processes by secreting histamine anf heparin?
Basophils
Most strokes and heart attacks are caused by the abnormal clotting of blood in an ubroken vessel. Moreover, a pieceo of the _____ may break loose and being to travel in the bloodstream as an ______.
thrombus; embolus
What is not normally found in plasma
Glycogen
The main reason why an individual with Type AB, Rh- negative blood cannot donate blood to an individual with Type A, Rh-positive blood is because ______
anti- B antibodies in the recipent will agglutinate RBCs of the donor
What would not decrease the blood colloid osmotic pressure?
a diet predominatly based on meat
What is not a function of blood
produces plasma hormones
the number of _____ typically increases in response to bacterical infections.
neutrophils
a defiency of _____ can cause permicious anemia
vitamin B12
What are the most abundant agranuocytes
Lymphocytes
Blood clots in the limbs put a patient most at risk for ______
pulmonary embolism
Which of the following might be injected into apatient who is prone to forming blood clots and therefore at risk of a heart attack or stroke
Heparin
What is not true of a patient with anemia
their blood viscosity is increased
What is the most abundatn protein in plasma
Albunin
Leukopoiesis beigns with the differentation of
pluripotent stem cells
Why are pregnant Rh- women given an injection of Rh immune globulin?
Antibodies in the injection bind fetal RBC antigens so they cannot stimulate her immune systen to produce anti- D antibodies.
During coagulation, which of the following is found in the extrinsic mechanism only?
Thromboplastin
What is the function of thromboplastin in hemostasis
it initiates the exstrintic pathway of coagulation
The ABO blood group is determined by _____ in the plasma membrace of RBC’S
glycolipids
A patient is suffering from ketoacidosis caused by an unregulated high protein diet. Which functions of the blood has been compromised ?
stabilizing the bodys pH
Some lymphocytes can survive as longas
decades
What is not true regarding sickle-cell disease?
it is a cause of malaria
Erythrocytes transport oxygen and ______
transport some carbon dioxide
When a clot is no longer needed, fibrin is dissolved by ______
plasmin
What is not secreted by platelets?
thrombopoletin
Where in the body are hemopoietic stem cells found?
red bone marrow
Serum is essentially identical to plasma except for the absence of _________
fibrinogen
What is the final product of the breakdown of the organic nonprotein moiety of hemoglobin?
Bilirubin
The strutural framework of blood clot is fromed by ________
a fibrin polymer
Platelets release ______ a chemical vasoconstrictor that contributes to the vascular spasm
serotonin
Most oxygen is transported in the blood bound to ______
heme groups in hemoglobin
Which of the following is not contained in the buffy coat
Erythrocytes
Which of the following proteins is not normally found in plasma
Hemoglobin
Where do most RBC’s die
spleen and liver
Where are most clotting factors synthesized in the body?
liver
What is most likely to cause anemia
renal disease
Tissues can become edematous (swollen) when which of the following occurs?
there is a dietary protein deficiency
An increased Erythopoietin (EPO) output by the kidneys would lead to all of the following except?
increased hypoxemia
Which of the following has not been implicated in causing leukopenia
Dehydration
The viscosity of blood is due more to the presence of ______ than to any other factor
erythrocytes
What would not lead to polycythemia
iron deficiency
what is nota feature of cardiac muscle
they have about the same endurance as skeletal muscle fibers.
Most of the ventricle filing occurs _____
during atrial diastole
the shallow depression seen on the external surface of the heart between left and right ventricles is called the ________
intreventricular sulcus
Opening and closing of the heart valves is caused
pressure gradients
Atrial depolarication caused the
P wave
The ________ valve regulates the flow of blood between the right ventricles and the vessels leading to the lungs
Pulmonary
In a normal ECG, the deflection that is generated by ventricular repolarization is called the ________
T wave
Stroke volume is increased by
increased venous return
Mitral valve prolaspe generates a murmur associated with the _______heart sound that occurs when the _______-
lubb (51); ventricles contract
When sodium channels are fully open, the membrane of the ventricular cardiomyocte__________
sharply depolarizes
What is not a part of the cardiac conduction system?
Tendinous cords
When the ventricles relax, the _______ valve prevents backflow of blood into the left ventricle.
Aortic
Isvolumetric contraction occurs during the _________ of the electrocardiogram
R wave
When the left ventricle contracts, the _________ valve closes and the _________ valve is pushed open.
mitral; aortic
The right atrioventricular valve (tricuspid) regulates the opening between the ________ and the ________
right atrium; right ventricle
The ________ performs the work of the heart
myocardium
An extended period of time between the P wave and the QRS complex may indicate what?
the signal is taking too long to get to the AV node
The volume of blood ejected by each ventricle in one minute is called the __________
cardiac output
Obstruction of the _______ will cause a more severe myocardial infacrtion than the obstruction of any of the others.
left coronary artery
What carrys oxygen poor blood
venea cava and pulmonary arties
The long absolute refractory period of the cardiomyocytes
prevents tetanus
Mitral valve prolapse causes blood leak back into the _________ when the ventricles contract
Left atrium
The ________ are the superior chambers of the heart
atria; ventricles
Atrial systole begins
immediately after the P wave
If the Sinoatrial node is damanged, the heart will likely beat at _________bpm
40 to 50
The plateau in the action potential of cardiac muscle results from the action of ___________
slow Ca2+ channels
Assume that the left ventricle of a childs heart has an EDV=90mL, and ESV=60mL, and a cardiac output of 2,400 ml/min. His SV is ___________ml/beat and his HR is ________
30; 80
Electrical signals pass between cardiomyocytes through the
gap junctions
Which is the correct sequence of events of the cardiac cycle
Ventricular filing—-> isvolumetric contraction—> ventricular ejection—>isovolumetric relaxation
Which of the following belongs to the pulmonary circuit
Pulmonary arteries and pulmonary veins
What is a feature shared by cardiac muslce and skeletal muscle
muscle fiber striations
The _______ is the pacemaker that initiates each heart beat.
Sinoatrial node
After entering the right atrium, the furthest a red blood cell can travel is the ________
superior vena cava
Oxygen poor blood passes through the
tricuspid and pulmonary arties
Pericardial fluid is found between the _______ and the __________
parietal; visceral membranes
The chordae tendinae of the AV valves are anchored to the _______ of the ventricles .
papillary muscles
What blood vessels recieves blood directly from the right ventricule?
pulmonary trunk
the heart is located in the space called the
mediatinum
Which of the following is the most superficial layer enclosing the heart?
parietal pericardium
Congestive heart failure of the right ventricle_______
can cause systemic edema
Any abnormal cardiac rhythm is called_____
arrhythmia
Cells of the sinoatrial node _______ during the peacemaker potential
depolarize slow
The frank-sterling law of the heart states that stroke volume is proportional to _______
the end-diastolic volume
The _________ carry blood toward the lungs
pulmonary trunk and artries
During isovolumetric contraction,the pressure in the ventricles_________
rises rapidly
Hypertension is commonly considered to be chronic resting blood pressure higher than
140/90
Where is the greatest volume of blood found in the body
veins
what is the most important force driving reabsorption at the venous end of capillary
blood colloid osmotic pressure
What is true about TIAs
often early warning signs of an impending stroke
During exercise, arterioles to the skeletal muscles
dilate in response to increased muscle metabolites
which of the following is absent in humans
right and left brachiocephalic arteries
How is venous return to your heart affected when you go for an easy jog
it is increased due to increased skeletal muscular pump activity
Which of the following is a portal system
heart –> artery–> arteriole –> capillary bed –> arteriole –> capillary bed –> venule –> vein –> heart
What is the most important force driving filtration at the arterial end of a capillary
blood hydrostatic pressure
What does the medullary ischemic reflex result in
increased circulation to the brain
What causes reactive hyperemia to increase tissue perfusion
local controls
If someone falls and suffers a trauma what do you do
lie them down and elevate their legs
a bee sting can trigger a massive release of histamine, which causes ______ and a(n) ________ in arterial blood pressure
vasodiliation; decrease
What is the most important force in venous flow?
the pressure generated by the heart
Pulmonary arteries have _________ blood pressure compared to systemic artries
considerably lower
The lungs receive a systemic blood supply by way of which vessel(S)
Bronchial arteries
What are powerful vasoconstrictors
Norepinephrine and angiotension II
Which of the following does not contribute to venous return
widespread vasodilation
A mean arterial pressure below 60 mmHg can casue what?
Syncope
What contributes the principal venous drainage of the thoracic organs
the azygos system
Myocardial infarction can lead to what type of shock
Cardiogenic
Why does our blood pressure go up as we age
our arteries get “hard” and absorb less systolic force
Which vessels have the thickest tunica media
large arteries
Alternative route of blood supply is called..
anastomoses
Where is the vasomotor center located
medulla oblongta
Which vessel supplies 80% of the cerebrum
internal carotid artery
What decreases blood pressure
Natriuretic peptides
What would decrease the velocity of blood flow
increased viscosity
What is taken up by the capillaries at their venous end
waste products
What is associated with vasomotion
smooth muscle in the tunica media
What type of shock occurs when bacterial toxins trigger vasodilation and increase capillary permeability
septic
what activities would fatigue your hand muscles the fastest
squeezing a ball as hard as you can without stoppin
What would decrease capillary filtration
dehydration
What best describes the cerebral arterial circle (circle of willis)
an anastomosis surrounding the pituitary gland
