Circulatory System Flashcards
(170 cards)
1
Q
How can varicose veins be surgically treated?
A
lasers that cause the blood vessel to scar over with connective tissue fibrosis and the blood vessel shuts down
2
Q
Do medium muscular veins contain laminae?
A
only internal elastic lamina
3
Q
____ is the cell death and loss of function associated with a vessel occlusion from a clot in the brain.
A
Cerebral infarct
4
Q
What can valvular incompetence lead to?
A
a murmur (blood leaking)
5
Q
What is the gradual narrowing of an artery by plaque formation called?
A
stenosis
6
Q
Elephantiasis is characterized by large amounts of fluid accumulation in the lower limbs. Why?
A
small worms hang out in the lymph and eventually block the vessels, which causes a huge amount of buildup in the affected body part
7
Q
What are the sites of exchange between blood and tissues?
A
capillaries
8
Q
What are metarterioles characterized by?
A
a discontinuous layer of smooth muscle in the tunica media
9
Q
Where would you find discontinuous capillaries?
A
in the liver, spleen, bone marrow
10
Q
When blood vessels dilate to form thin-walled, ballooned regions, they are called ___.
A
aneurisms
11
Q
Which capillaries have a basal lamina that is not continuous, where the cells are separated by large gaps?
A
discontinuous
12
Q
What does the tunica adventitia contain in larger vessels?
A
vasa vasorum
13
Q
What regulates the distribution of blood to capillaries?
A
pre-capillary sphincters (intermittent rings of smooth muscle within walls of arterioles)
14
Q
What are the specialized, discontinuous tight junctions between endothelial cells called?
A
fascia occludens
15
Q
In general, the amount of smooth muscle ___ with an increased diameter of vessel and the relative amount of connective tissue ___.
A
increases; decreases
16
Q
Which type of artery has more smooth muscle and less elastin in tunica media than elastic arteries?
A
muscular arteries
17
Q
The highly variable middle layer is called the tunica ___.
A
media
18
Q
How does the heart heal?
A
through fibrosis
19
Q
What are the smallest arterioles?
A
metarterioles
20
Q
What are capillaries supported by?
A
basal lamina and small number of pericytes
21
Q
What is the primary function. of the circulatory system?
A
transport O2, CO2, nutrients, and metabolic wastes
22
Q
By how much can coronary arteries decrease in diameter due to atherosclerosis?
A
90%
23
Q
These vessels are small veins that lack elastic laminae and may lack tunica media.
A
venules
24
Q
Which tunica layer is the outermost layer?
A
tunica adventitia
25
Lymph is formed as a result of ___ static pressures in arterioles.
high
26
This layer consists of loose fibroblastic tissue (fibroblasts, collagen, elastic fibers) and smooth muscle cells.
tunica adventitia
27
___ contain large amounts of elastic and smooth muscle and the vessel wall very thick relative to lumen diamter.
Arteries
28
Can vaso vasorum run with both arteries and veins?
YES; large vessels only
29
The contraction of ventricles is ___; the relaxation of ventricles is ___.
systole; diatole
30
Where are the sheets of elastic tissue located in elastic arteries?
tunica media (maintains blood pressure)
31
What material is exposed if the plaque enlarges or the endothelium becomes damaged?
collagen
32
Is the internal elastic lamina always present?
NO; if it is, it will be between the tunica intima and tunica media
33
What does the nervi vasculares do?
vasoconstriction and vasodilation (controls the smooth muscle contraction in the vessel walls)
34
In smaller vessels, what takes over the support function?
connective tissue (versus smooth muscle in large vessels)
35
___ and ___ are terminally differentiated.
Neurons; cardiac muscle
36
What is the innermost tunic layer lining the lumen?
tunica intima
37
What are the two components of the circulatory system?
pulmonary circulation and systemic circulation
38
What are the elastic arteries?
aorta
common carotid
subclavian
pulmonary
39
How is vasodilation and vasoconstriction accomplished if capillaries do not exhibit these capabilities?
smooth muscle of arterioles and pre-capillary sphincters
40
Do capillaries have smooth muscle in their walls?
NO - no tunica media (so no vasomotor activity)
41
What does the blood vascular system consist of?
heart and blood vessels
42
What happens when the inflammatory response to cholesterol becomes chronic?
atherosclerosis and plaque formation (phagocytosis can cause this phenomena)
43
AV shunts are common in skin and are a type of ___.
anastomosis
44
What substance adheres to the damaged, exposed proteins of the endothelial wall?
cholesterol (later reabsorbed)
45
What is the part of the circulatory system concerned with exchange of gases, fluids, nutrients, metabolites, and waste products?
microcirculation
46
Where is the lymph returned back to the bloodstream?
at the junction of the left internal jugular vein and the left subclavian vein
47
Can the amount of subendothelial connective tissue vary?
YES; depends on size of the blood vessel
48
Vasodilation is ___ and occurs in the absence or inhibition of sympathetic stimulation.
passive (+ controversial)
49
What is a characteristic of matured atherosclerotic vessel walls?
proliferation of smooth muscle cells and formation of fibrous connective tissue capsule
50
What happens when the cells within the plaque start to die?
necrosis and "hardening" or calcification of the artery walls
51
What facilitates diapedesis both chemically and mechanically?
the intercellular spaces are enlarged by substances like serotonin, which then increases the permeability of the vessels
52
Where does microcirculation occur?
within capillaries (but also arterioles and venules)
53
What is atherosclerosis associated with clinically?
increased blood pressure (from decreased lumen diameter and increased systolic bp - Bernoulli)
54
If the vessel becomes occluded it is referred to as ___.
thrombosis
55
What type of endothelial cells is the tunica intima made of?
simple squamous endothelial cells (lines lumen)
56
On which layer do sympathetic, post-ganglionic nerve fibers act on the muscle to induce vasoconstriction?
tunica media
57
___ and ___ have thicker tunica adventitia as they are larger vessels than venules.
Collecting venules; muscular venules
58
Which sensory receptors are located in the carotid sinus and aortic arch?
baroreceptors
59
What is a piece of thrombus called when it breaks off?
embolus (leads to thromboembolic disease)
60
What is the passive drainage system called that returns lymph (extravascular fluid) to blood vascular system?
lymph vascular system
61
What is the most common cause of ischemic heart disease?
atherosclerosis
62
Will smaller muscular arteries have an external elastic lamina?
NO
63
What controls the luminal diameter of muscular veins and venules (similar for arteries)?
the amount of smooth muscle in the tunica media
64
What maintains blood pressure?
the expansion and recoil of elastic arteries (forces blood into the conducting vessels)
65
The ____ is composed of smooth muscle cells (majority) and fibroblastic connective tissue.
tunica media
66
___ are important in neovascularization and wound healing.
Pericytes
67
___ and ___ are specialized sensory receptors located in the walls of blood vessels.
Baroreceptors; chemoreceptors
68
What is the purpose of the vaso vasorum despite the fact that there is a large vessel right below it?
after a few layers, the blood supply is unable to reach the cells below it, so the vaso vasorum supplies these cells with oxygen
69
When the colloidal oncotic pressure is exceeded, the pressure of plasma proteins leads to ____.
the leakage of water, electrolytes, and plasma proteins from capillaries into extracellular space (to be picked up by lymphatic system)
70
In response to low O2 tension, smooth muscle in walls of arterioles relaxes, which results in ____.
vasodilation
71
The arterial system conducts blood ____ the heart.
away from
72
Do elastic arteries possess both internal and external elastic laminae?
YES
73
What is the cyclical pumping of the heart called?
pulsatile blood flow
74
What is the most common acquired abnormality of blood vessels?
atherosclerosis or arteriosclerosis
75
What is indicative of venous valve failure?
varicose veins
76
What principle is affiliated with the change in diameter of blood vessels and relative pressure?
Bernoulli's Principle
77
Are there elastic laminae in arterioles?
NO
78
These small vessels are the major site of vasoconstriction and vasodilation.
arterioles
79
What kind of barrier does the tunica intima form?
semi-permeable, supported by basement membrane
80
How does transport across capillaries occur?
via fenestrae, transcytosis or diapedesis
81
Foam cells contain large amounts of ____ in the cytoplasm.
cholesterol
82
How do cancers metastasize?
by utilizing the blood circulatory system and lymphatics
83
What vasoactive substances can act on venules?
histamine, serotonin
84
Where do white blood cells exit circulation?
at post-capillary venules
85
In the circulatory system, cholesterol has a similar function to ___.
platelets
86
What do valves in veins prevent?
backflow (especially in limbs and thorax)
87
What do larger lymph vessels possess that smaller lymph vessels do not?
contractile ability due to tunica media
88
What is the associated pain called due to a decrease in O2 available to the heart?
angina
89
Besides small blood vessels, what else is contained within the tunica adventitia?
nervi vasculares (autonomic nerves)
90
Which capillaries have an endothelium with a continuous lining? Where are these found?
continuous (muscle, lungs, CNS)
91
How is extracellular fluid drained?
by a series of interconnected, blind-ending tubules (lymphatics)
92
What is the system of blind-ending, interconnected tubules?
lymphatic system
93
The lymph vascular system lacks ____ and relies on muscle contraction and body movement to move lymph.
intrinsic pump (valves)
94
What layers of tunica do capillaries lack?
tunica media and tunica adventitia
95
What do the terminal branches of the arterial system supply?
capillary beds
96
What is the pathway of systemic circulation?
left atrium + ventricle >> aorta >> rest of the body
97
The internal elastic lamina is composed of ____ fibers.
elastic
98
How does thrombus formation result from plaques?
when plaques damage the vessel wall, it triggers the intrinsic pathway of the clotting cascade which initiates thrombus formation
99
___ detect blood pressure using sensory mechanisms (stretch sensors).
Baroreceptors
100
What does the area of the infarct look like?
black and necrotic
101
Large and medium-sized veins are called ____ veins.
muscular
102
Which kind of artery is greater than 1 cm in diameter and receive blood directly from the heart?
elastic arteries
103
In ____ venules, both the tunica media and tunica adventitia are reduced or absent.
post-capillary
104
Why would you want a "leaky" capillary?
because in some tissues there are materials that need to be released or absorbed easily (hormones, large macromolecules)
105
____ of blood vessels occurs due to action of sympathetic, post-ganglionic nerve fibers.
Vasocontriction
106
Do lymph vessels contain valves?
YES - and potentially a basement membrane or pericytes
107
What color are each of the stained squiggles in the tunica media histological slide?
yellow - smooth muscle
pink - collagen
dark - elastic fibers
108
These arteries contain a distinct internal elastic lamina.
muscular arteries
109
What is the secondary function of the circulatory system?
thermoregulation, transport of immune cells and hormones
110
Which sensory receptors are located at the bifurcation of the carotid artery and in aortic bodies in the aortic arch?
Chemoreceptors
111
What are sinusoids?
large diameter discontinuous capillaries
112
How is the movement of lymph accomplished?
skeletal muscle contraction
113
Are the spaces between cells in discontinuous capillaries fenestrae?
NO - these are different
114
What are lymph endothelial cells highly activated in?
phagocytosis
115
The sudden occlusion by an embolus is referred to as a ____.
sudden ischemic event
116
What forms around a plaque in the bloodstream?
a capsule
117
Lymph vessels are most similar to ___.
veins
118
How big is a capillary?
barely bigger than a red blood cell
119
If present, this layer is located between the tunica media and tunica adventitia.
external elastic lamina
120
Which vessels contain pre-capillary sphincters?
arterioles
121
An oncologist is deciding the best course of treatment for her patient with breast cancer. The decision between a unilateral or a bilateral mastectomy is based on ___.
the asymmetry of the thoracic lymph ducts and if the cancer has metastasized
122
Is there a tunica media in lymph vessels?
yes - very thin
123
The regulation of blood pressure accompanied by changes in the diameter of the blood vessels occurs via ___.
sympathetic control of smooth muscle in vessel walls
124
Which capillaries have an endothelium that possess small pores within cells? Where are these found?
fenestrated (endocrine glands, GI tract)
125
Through what kind of stimulation and innervation may vasodilation occur?
via indirect parasympathetic innervation (endothelial cells release NO which causes smooth muscle cells to relax)
126
Where does fluid normally leave the circulatory system?
via capillaries
127
What leads to the fluid retention and swelling after an immune response?
the diapedesis of white blood cells allowing leakage of fluid into the space
128
What do fascia occludens allow?
diapedesis of white blood cells
129
Most of the adventitia is ___.
collagen
130
What are the two types of circulatory systems?
open and closed (invertebrates)
131
What colors do proteins stain on H&E?
pink
132
How many layers of endothelial cells do capillaries have?
1
133
Cardiac myocytes are unable to regenerate. How are they differentiated?
terminally differentiated
134
Are the blood endothelial cells highly active in phagocytosis?
NO
135
What is the pathway of pulmonary circulation?
right atrium + ventricle >> pulmonary arteries >> lungs >> pulmonary veins >> left atrium
136
The venous system conducts blood ___ the heart.
towards
137
The inflammation of the AV valves leads to valvular incompetence which is called ___.
vegetative endocarditis (and thromboembolic disease)
138
What is the majority of the layer of the wall of a venule?
tunica intima
139
___ are direct connections between arterial and venous systems and bypass the capillary bed.
AV shunts
140
Where can aneurisms commonly burst?
aorta, brain
141
What cells are produced when the inflammatory response in the blood becomes chronic?
production of foam cells
142
What are vasa vasorum?
small blood vessels that supply the tunica media and adventitia in large arteries and veins
143
What is valvular incompetence?
the thickening of AV valves associated with increases turbulence and regurgitation
144
____ act like traps and contain lymphoid tissue for sampling and activate the immune cells to produce antibodies.
Lymph nodes
145
The external elastic lamina is also composed of elastic fibers, but they are ___ organized compared to the internal elastic lamina.
LESS
146
What is the function of the lymphatic system?
it drains excess fluid (lymph) from the extracellular space and returns it to the bloodstream
147
Do large muscular veins contain laminae?
BOTH internal and external laminae
148
___ detect changes in O2, CO2 tension, and pH levels using sensory mechanisms.
Chemoreceptors
149
Is thoracic drainage symmetrical or asymmetrical?
asymmetrical
150
Lymph vessels have ___ permeability and ___ walls than veins.
greater; thinner
151
In arteries, it is the thickest of the layers and may contain reticulin and elastic fibers, which are ___ collagen.
tunica media; Type III collagen
152
Where to pericytes originate from?
the same precursor cells as endothelial cells
153
Which is thicker in the venous system, the tunica media or tunica adventitia?
tunica adventitia
154
What phase are cardiac myocytes "stuck in?"
Go phase
155
____ contain relatively little smooth muscle (tunica media only a few cells thick).
Arterioles
156
Where does the lymphatic system converge?
thoracic duct and right lymphatic duct
157
Do invertebrates use their circulatory system for oxygenating tissues?
NO
158
What is the function of the venous system?
functions as a low pressure collecting system for returning blood from capillaries to the heart
159
What is the purpose of a shunt?
to bypass a capillary bed
160
What is "death by ischemia?"
myocardial infarction
161
Where is the preferential site for diapedesis of white blood cells?
post-capillary venules
162
Why does immobility lead to edema (swelling)?
there is very limited skeletal muscle contraction to pump the lymph upwards in the body
163
Why does lymph fluid stain light pink?
because lymph is a high protein fluid
164
Can pericytes contract and differentiate?
YES - into endothelial or smooth muscle cells after injury
165
The tunica ___ is the thickest layer in arteries; the tunica ___ is the thickest layer in veins.
media; adventitia
166
Blood vessels of the circulatory system have a common basic structure of ___.
3 concentric layers called tunics
167
What is a vein or artery that directly connects two capillary beds?
portal vessels (hepatic portal, venous portal)
168
What is the characteristic "sine-wave" shaped dark layer located directly under the tunica intima?
internal elastic lamina
169
Will all muscular arteries have an internal elastic lamina?
YES
170
Why is fibrotic healing not as effective as the original matrix?
connective tissue has less contractile ability and function as cardiac muscle (so this results in a loss of function)
