Worksheet IV:
Circulatory System-Vessels
1. _________________________ proposed the existence of
capillaries and outlined the circulation pattern we understand today.
2. Name the 3 layers of arteries and veins from outermost to
innermost.
______________________________
______________________________
______________________________
3. The tunica media is divided into 2 layers; an outer layer of __a__
muscle innervated by the __b__ (Which ANS division?) and an inner layer
of __c__ connective tissue. This __c__ layer is much __d__
(larger/smaller) in arteries.
a. ______________________________
c. ______________________________
b. ______________________________
d. ______________________________
4. Identify the tunic of blood vessels based on the information given
below.
a. Vasa vasorum present.
_______________________________
b. Composed of endothelium.
_______________________________
c. Composed of simple squamous
epithelium.
_______________________________
d. Responsible for vasodilation and
vasoconstriction. _______________________________
e. Anchors and protects vessels.
_______________________________
f. Composed of smooth muscle and elastic
fibers. _______________________________
g. This tunic is absent in venules.
_______________________________
h. This tunic is absent in arterioles.
_______________________________
i. Only tunic present in capillaries.
_______________________________
5. __a__ transport blood away from the heart and usually carry
__b__ (oxygenated/deoxygenated) blood. The exception to this
pattern for __a__ is the __c__. __d__ transport blood towards the
heart and usually carry __e__ (oxygenated/deoxygenated) blood.
The __f__ is the exception to this pattern for __d__.
a. ______________________________
d. ______________________________
b. ______________________________
e. ______________________________
c. ______________________________
f. ______________________________
6. Name the 3 kinds of arteries.
______________________________
______________________________
______________________________
7. Identify the kind of artery based on the information given
below.
a. Contain elastic lamina.
______________________________
b. Thick-walled, large diameter, large amounts of
elastic
tissue.
______________________________
c. Carry blood to specific organs; e.g. splenic,
gastric,
hepatic, etc.
______________________________
d. Smallest in diameter; only 2 tunics.
______________________________
e. Lumen is less than 0.5 mm in
diameter.
______________________________
f. Most important in vasoregulation.
______________________________
g. Tunica media is mostly smooth muscle; medium
diameter. ___________________________
8. List 5 characteristics of veins.
_____________________________________
_____________________________________
_____________________________________
_____________________________________
_____________________________________
9. The largest veins are:
______________________________.
10. Dilated veins with malfunctioning valves are called __a__
veins. __a__ veins of the anal canal are called __b__. Give
3 factors that influence the formation of __a__ veins: __c__, __d__,
and __e__.
a. ______________________________
d. ______________________________
b. ______________________________
e. ______________________________
c. ______________________________
11. List 3 kinds of capillaries.
______________________________
______________________________
______________________________
12. Identify the kind of capillary based on the information given below.
a. Highly modified, very leaky capillaries in liver,
marrow,
and lymphoid tissues.
______________________________
b. Important in slowing blood flow for
processing. ______________________________
c. Endothelium cells united by tight
junctions.
______________________________
d. Abundant in skin and muscles.
______________________________
e. Great permeability, endothelial cells riddled
with pores. _____________________________
f. Found where absorption occurs; e.g. small
intestine,
kidneys, and endocrine organs.
______________________________
13. An interweaving group of capillaries is called a(n)
__a__. The part of the __a__ where an artery connects directly to
a vein is called the __b__. Exchange of gases, nutrients, or
wastes __c__ (does/does not) occur in __b__. __d__, however,
branch off the __b__ on the arteriole end and return to the __b__ at
the venule end. Gases, nutrients, and wastes __e__ (are/are not)
exchanged in __d__. __f__, smooth muscle valves, surround
each root of a __d__ and regulate blood flow.
a. ______________________________
d. ______________________________
b. ______________________________
e. ______________________________
c. ______________________________
f. _______________________________
14. List 3 kinds of openings or transport methods in
capillaries. ______________________________
______________________________
______________________________
15. Give the mean pressure value for the vessels listed below.
Aorta __________________________
Arteries ________________________
Arterioles _______________________
Capillaries ______________________
Venules ________________________
Veins __________________________
Vena cavae _____________________
16. Name 4 factors that affect arterial (blood) pressure.
_______________________________
_______________________________
_______________________________
_______________________________
17. Of the 4 factors listed in question #16, the most important
is __a__. __a__ is the most important because __a__ varies
inversely with the 4th power of the vessel __b__. Therefore,
small changes in __c__ can produce __d__ changes in __a__.
a. ______________________________
c. ______________________________
b. ______________________________
d. ______________________________
18. __a__ is defined as the amount of pressure exerted on the
inside of a vessel wall. __b__ directly affects __a__ because
__a__ is equal to __b__ times peripheral resistance. If __b__ is
increased and peripheral resistance is held constant, then __a__ will
__c__ (increase/decrease/remain unchanged).
a. ______________________________
c. ______________________________
b. ______________________________
19. If blood volume is __a__ (increased/decreased/not affected) because
of hemorrhage or dehydration then blood pressure will __b__
(increase/decrease/not be affected).
a. ______________________________
b. ______________________________
20. If blood viscosity is __a__ (increased/decreased/not affected)
because of polycythemia then blood pressure will __b__
(increase/decrease/not be affected).
a. ______________________________
b. ______________________________
21. Many factors control blood pressure. __a__ or local controls
make automatic adjustments in blood flow in direct proportion to
requirements. Organs regulate their own blood flow by
vasoconstriction or vasodilation. Receptors for stretch, pH, and
chemicals use reflex arcs to make adjustments in pressure. In general,
receptors send information via __b__ neurons to the __c__ center in the
medulla. __d__ neurons send messages out to __e__ effectors in
blood vessels. Specifically, increased vessel diameter activates
__f__ which __g__ (increases/decreases) the number of impulses going to
the __c__ center. The __c__ center __h__ (excites/inhibits) __d__
neurons going to __e__ effectors (muscle type) and this causes __i__
(vasoconstriction/vasodilation) and as a result __j__
(increases/decreases) blood pressure. The __c__ works via reflex,
but can also be modified by higher brain centers such as the __k__ and
__l__.
a. ______________________________
g. ______________________________
b. ______________________________
h. ______________________________
c. ______________________________
i. _______________________________
d. ______________________________
j. ______________________________
e. ______________________________
k. ______________________________
f. ______________________________
l. _______________________________
22. __a__ receptors detect changes in blood oxygen or pH. These
receptors are found in the __b__ and __c__ bodies. These
receptors are less important in modifying blood pressure, but are more
important in modifying the rate and depth of __d__.
a. ______________________________
c. ______________________________
b. ______________________________
d. ______________________________
23. Name 7 chemicals that affect blood pressure, tell whether
they increase or decrease blood pressure, and how they initiate the
change.
Chemical
Change caused if released How
effect is caused. ____________________
_____________________
___________________________________
____________________
_____________________
___________________________________
____________________
_____________________
___________________________________
____________________
_____________________
___________________________________
____________________
_____________________
___________________________________
____________________
_____________________
___________________________________
____________________
_____________________
___________________________________
24. The __a__ (Give organ.) controls blood pressure by tubular
reabsorption and secretion. It also can control BP by releasing the
hormone __b__.
a. _______________________________
b. ________________________________
25. Name 4 forces that move substances across a capillary's
endothelium.
_______________________________
_______________________________
_______________________________
26. What 3 categories of substances move across a capillary wall by
diffusion?
_______________________________
_______________________________
_______________________________
27. Identify the forces that move fluids across the capillary
endothelium based on the information given below.
a. Force caused by large nondiffusible substances in
fluids. _____________________________
b. Force or pressure exerted by the interstitial
fluids outside
of capillaries.
_______________________________
c. Force exerted by a fluid pressing against (from
inside
out) a vessel wall.
_______________________________
d. Force created by albumins in plasma of
capillaries. _______________________________
e. Force created by solutes present in interstitial
fluids. _______________________________
28. Answer the following questions about fluid movements in a capillary.
a. Capillary hydrostatic pressure (HPc) at the
arterial end
of a capillary.
_______________________________
b. HPc at the venous end of a capillary.
_______________________________
c. Direction (into capillary or out of capillary)
that fluids
are forced by HPc-arterial end.
_______________________________
d. Direction (into capillary or out of
capillary) that fluids
are forced by HPc-venous end.
_______________________________
e. Interstitial fluid hydrostatic pressure (HPif) at
the arterial
end of a capillary.
_______________________________
f. HPif at the venous end of a
capillary.
_______________________________
g. Direction (into capillary or out of capillary)
that fluids
are forced by HPif-arterial end.
_______________________________
h. Direction (into capillary or out of
capillary) that fluids
are forced by HPif-venous end.
_______________________________
i. Net hydrostatic pressure (HPnet) at the arterial
end
of a capillary.
_______________________________
j. HPnet at the venous end of a
capillary.
_______________________________
k. Direction (into capillary or out of capillary)
that fluids
are forced by HPnet-arterial end.
_______________________________
l. Direction (into capillary or out of
capillary) that fluids
are forced by HPnet-venous end.
_______________________________
m. Osmotic pressure (OPc) in the
capillary.
_______________________________
n. OP of the interstitial fluids
(OPif).
_______________________________
o. OPnet along the capillary.
_______________________________
p. Direction (into capillary or out of
capillary) that fluids
are forced by OPnet.
_______________________________
q. Fluids will leave capillaries
if:
_______________________________
r. Is HP greater than or less than OP at the
arterial end? _______________________________
s. Refer to r. Which direction do fluids move at the
arterial
end of the capillary?
_______________________________
t. Is HP greater than or less than OP at the venous
end? _______________________________
u. Refer to t. Which direction do fluids move
at venous
end of the capillary?
_______________________________
v. Therefore there is net a fluid loss at the
(arterial or
venous end):
_______________________________
w. Lost fluids are returned to main circulation by
the: _______________________________
29. How does the aorta act as a second heart?
_____________________________________________
___________________________________________________________________________________
30. Outline the reflex arc for vasomotor control.
____________________________________________
___________________________________________________________________________________
31. What is the difference between hydrostatic and osmotic
pressures? __________________________
___________________________________________________________________________________
32. Why would a soldier be told to wiggle his toes in his boots when he
is standing at attention for a long period of time?
_______________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
33. Why do veins tend to collapse more than arteries when they
are placed on a slide? _____________
___________________________________________________________________________________
34. What kind of problems would a person with diabetes insipidus have
with his blood pressure? Why?
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
35. How would a high salt diet affect hydrostatic pressure and what
problems would this cause? _______
___________________________________________________________________________________
___________________________________________________________________________________
36. How are thoroughfare channels important in regulating blood flow?
___________________________
___________________________________________________________________________________
___________________________________________________________________________________
37. Which is the most important factor affecting arterial
pressure? Why? _________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
38. Excluding the heart, which is the most important organ affecting
blood pressure? Why? ___________
___________________________________________________________________________________
___________________________________________________________________________________
39. How would polycythemia vera affect blood pressure? Why?
________________________________
___________________________________________________________________________________
___________________________________________________________________________________
40. How can long term exercise actually lower one's blood
pressure? ___________________________
___________________________________________________________________________________
___________________________________________________________________________________
Answers: Worksheet IV-Vessels.
1. William Harvey
2. Tunica adventitia (externa), tunica media, tunica intima
(endothelium).
3. a. smooth
c.
elastic
b. Sympathetic NS
d. larger
4. a. Tunica externa
f. Tunica media
b. Tunica intima
g.
Tunica media
c. Tunica intima
h.
Tunica externa
d. Tunica media
i.
Tunica intima
e. Tunica externa
5. a. Arteries
d. Veins
b. oxygenated
e.
deoxygenated
c. pulmonary artery
f. pulmonary vein
6. Elastic, muscular, arterioles
7. a. Elastic
d.
Arterioles
b. Elastic
e.
Arterioles
c. Muscular
f.
Arterioles
g.
Muscular
8. Trasnport blood to the heart/Usually deoxygenated/Low
pressure/Thin walled and large diameter/Valves present.
9. Vena cavae
10. a. varicose
d.
Pregnancy
b. hemorrhoids
e. Long
periods of standing
c. Obesity
11. Continuous/Discontinuous (fenestrated)/Sinusoids
12. a. Sinusoid
d.
Continuous
b. Sinusoid
e.
Discontinuous
c. Continuous
f.
Discontinuous
13. a. capillary bed
d. True
capillaries
b. thoroughfare channel
e. are
c. does not
f.
Precapillary sphincters
14. Intercellular clefts/Pinocytic vesicles/Membrane pores.
15. aorta-between 90 and 120/arteries-betw 80 and
110/arterioles-betw 60 and 80/capillaries-betw 20 and 40/venules-betw
15 and 20/veins-betw 5 and15/vena cavae-between 2 and 5. All
values in mmHg.
16. Cardiac output/Blood volume/Peripheral resistance/Viscosity
17. a. peripheral resistance
c.
diameter (radius)
b. radius
d. large
18. a. Blood pressure
c. increase
b. Cardiac output
19. a. decreased
b.
decrease
20. a. increased
b.
increase (The heart has to work harder to
move thicker blood.)
21. a. Autoregulation
g. increases
b. sensory
h.
inhibits
c. vasomotor
i.
vasodilation
d. motor
j.
decreases
e. smooth muscle
k. cerebral cortex
(hypothalamus)
f. mechanoreceptors (baroreceptors or
l. hypothalamus (cerebral cortex)
pressoreceptors)
22. a. Chemoreceptors
c. aortic (carotid)
b. carotid (aortic)
d. breathing
23. Angiotensin II, increases BP, by vasoconstriction/Vasopressin,
increases BP, by vasoconstriction/E, increases BP, by increasing heart
rate and vasoconstriction/NE-basically the same as E/Atrial natriuretic
factor, decreases BP, by increasing Na+ excretion and therefore water
loss, water loss decreases blood volume which decreases BP/Aldosterone,
increases BP, increases Na+ absorption causing water retention which
increases blood volume which increases BP/ADH, increases BP, by causing
kidneys to conserve water which raises blood volume which increases BP.
24. a. kidney
b. renin
25. diffusion, endocytosis, exocytosis, hydrostatic pressure
26. lipid-soluble, water, and water soluble substances
27. a. Osmotic pressure
d.
Osmotic pressure in capillaries OPc
b. Interstitial fluid hydrostatic pressure
(HPif) e. Osmotic pressure in interstitial fluid
(OPif)
c. Hydrostatic pressure of capillary (HPc)
28. a. 32 mmHg
m. 25
mmHg
b. 15 mmHg
n.
3 mHg
c. fluids forced out of capillary by HP
o. 25 - 3 = 22 mmHg
d. fluids forced out of capillary by HP
p. Fluids pulled back into capillary by OP
e. difficult to measure, probably negative
but q. netHP > net OP
we will use 0.
r. HP
> OP arterial end
f. same as in e.
s.
Fluids are forced out of capillary at arterial g.
Fluid movement not affected if value is 0, end.
but will be pulled out if negative.
t. HP < OP venous end
h. Same as in g.
u. Fluids are pulled back
into capillary at
i. netHPart end = 32 - 0 = 32
mmHg venous end.
j. netHPven end = 15 - 0 = 15mmHg
v. arterial end
k. Forces fluids out of capillary at arterial
end. w. lymphatic system
l. Forces fluids out of capillary at venous end.
29. The aorta is an elastic artery. The elastic stretches with each
ventricular contraction and ,as a stretched rubber band would do when
the tension is released, the artery recoils and pushes the blood onward.
30. Baroreceptor---sensory neuron---vasomotor center in medulla--motor
neurons (ANS)--smooth muscle effector in vessel wall.
31. Hydrostatic pressure is the force exerted by a liquid outward on
the inner wall of a vessel (or even your garden hose) while osmotic
pressure is caused by differences in solute concentrations on each side
of a membrane. Water is pulled from a hypotonic area to a
hypertonic area. The force that the moving water exerts on a cell
membrane is osmotic pressure.
32. Without the skeletal muscles massaging the veins that return blood
from the lower body, evntually blood begins to pool in the lower body
and away from the brain. The brain is deprived of oxygen, the
person faints, and blood flow returns to normal.
33.
* For question 28, pressure values vary. Therefore, you could
easily come up with different numerical values and be correct.
Just be consistent on what source you use and whatever numbers you
obtain. They should be in the same general direction and produce the
same general results as the numbers I have used.