chapter 19 homework
Blood is pumped into the pulmonary circuit from the
right ventricle
Where is the majority of blood volume located during rest?
systemic venous system
total peripheral resistance (TPR)
the amount of friction blood encounters during flow through blood vessels.
blood pressure
the force of the blood against the vessel wall.
Blood pressure would INCREASE as a result of a DECREASE in __________.
blood vessel diameter
RBCs move single file through this structure.
capillary
Which of the following changes would produce the greatest change in total peripheral resistance?
10% change in vessel diameter
In which of the following would the resistance be greater?
a vessel 10 microns in diameter
body conditions that affect blood volume:
blood donation and excessive sweating
physiological changes that increase BP:
increase TPR, increase blood vessel length, increase cardiac output, increase blood volume, increase blood viscosity
physiological changes that decrease BP:
increased blood vessel diameter
Each of the following changes will result in increased blood flow to a tissue except
increased hematocrit
Each of the following will cause an increase in blood pressure except
increased levels of ANP (atrial natriuretic peptide).
Turbulence __________.
increases resistance
Which of the following is true regarding the inferior vena cava?
it's considered a large vein
The brachial and femoral arteries are examples of which type of artery?
muscular
Blood pressure increases with all of the following except increased
parasympathetic innervation.
The right ventricle pumps blood to the __________.
pulmonary circuit
Blood moves forward through veins because of all of the following except
pumping by the smooth muscle in the wall of the vein
Natriuretic peptide release by the heart __________.
results in increased sodium loss in urine
Which chamber of the heart receives blood from the systemic circuit?
right atrium
These vessels hold the largest percentage of the blood supply.
systemic venous system
Total peripheral resistance is related to all of the following except
the osmolarity of interstitial fluids.
________ refers to all the factors that resist blood flow in the entire circulatory system.
total peripheral resistance
Which of the following is the innermost layer of a blood vessel?
tunica intima
The layer of the arteriole wall that can contains smooth muscle and can produce vasoconstriction is the
tunica media
Which layer of a blood vessel contains concentric sheets of smooth muscle tissue?
tunica media
Which wall layer is thicker in the artery than in the vein?
tunica media
List the factors that contribute to total peripheral resistance.
vascular resistance, vessel length, vessel luminal diameter, blood viscosity, and turbulence
Blood pressure is lowest in the
veins
Which of the following are the smallest venous vessels?
venules
When will the blood pressure be greater?
when the peripheral vessels constrict
Describe a capillary.
a small blood vessel whose thin wall permits exchange between blood and interstitial fluid by diffusion.
Each of the following will lead to a decrease in blood pressure except
release of renin
Describe the pulmonary circuit.
transports blood from the right ventricle through the pulmonary arteries, capillaries in the lungs, and pulmonary veins and returns it to the left atrium.
Describe the systemic circuit
transports blood through the arteries, capillaries, and veins of the body from the left ventricle to the right atrium.
Which of the following layers of a vessel contains collagen fibers with scattered bands of elastic fibers?
tunica externa
The process of decrease in any vessel diameter that occurs due to smooth muscle contraction is called
vasoconstriction
blood viscosity
the friction red blood cells encounter when moving past each other.
Why is it beneficial for capillary pressure to be very low?
It is beneficial for capillary pressure to be low to allow time for diffusion between the blood and the surrounding interstitial fluid.
Why are valves located in veins but not in arteries?
Valves are located in veins to prevent blood from flowing backward because venous pressure is too low to keep the blood moving back toward the heart.
When renin is released from the kidney,
angiotensin I formation is triggered.
cardiac output
the volume of blood pumped out by one ventricle each minute.
All of the following contributes to turbulent blood flow except
3rd and 4th heart sounds
List the five general classes of blood vessels
arteries, arterioles, capillaries, venules, veins
Where is blood pressure highest?
artery
Which of the following is not a characteristic of venous valves?
channeling blood away from the heart
Which of the following would have the greater effect on vascular resistance?
decreasing the diameter of a blood vessel by 1/2
The common iliac artery is an example of which type of artery?
elastic
Arrange the structures in the following list in the order that blood will encounter as it flows from the heart back to the heart in the cardiovascular circuit.
elastic arteries, muscular arteries, arterioles, capillaries, venules, medium-sized veins, large veins
How is blood pressure maintained in veins to counter the force of gravity?
Blood pressure is maintained in veins by the contractions of surrounding skeletal muscles that squeeze venous blood toward the heart and the presence of valves which prevent backflow of the blood.
Describe the distribution of total blood volume in the body.
The volume is divided into the systemic venous system (64%), systemic arterial system (13%), in the heart (7%), pulmonary circulation (9%), and systemic capillaries (7%).
What factors are involved in the formation of varicose veins?
form when the vein walls weaken and the valves fail so blood begins to pool in the veins.
Compared to arteries, veins
have thinner walls
Neural and endocrine regulatory mechanisms influence which factors?
heart rate, stroke volume, peripheral resistance, and venous pressure
body conditions that affect TPR:
high-altitude living, smoking, growth, increased sympathetic activity
Homeostatic mechanisms in response to blood loss include all of the following except
inhibition of EPO secretion.
The vein in the arm commonly sampled for blood by venipuncture is the
median cubital vein