A&P II_Exam II Flashcards
CIRCULATION (189 cards)
1
Q
Flow (Q) can also be related to?
A
Cross-Sectional Area (A) & Linear Velocity of flow (V)
2
Q
Cross-Sectional (Surface Area) area is _____ proportional to _____ of flow.
A
Inversley
Velocity
3
Q
Velocity of flow is slowest in ____ and fastest in ____.
A
Capillaries
Large Vessels
4
Q
Blood flow is the fastest in which of these vessels?
A. Aorta
B. Capillaries
C. Veins
D. Arterioles
A
A. Aorta
5
Q
Laminar Flow has greatest velocity in the ____ of the vessel
A
Center
6
Q
Laminar Flow has the lowest velocity near the ______.
A
Vascular Wall
7
Q
What is caused by shear stress produced as blood flows past stationary wall?
A
Streamlining
8
Q
What is the volume of blood flowing back to the heart through systemic veins?
A. Retrograde Artery Flow
B. Venous Return
C. Capillary Junction Flow
A
B. Venous Return
9
Q
What causes venous return decrease?
A
Pressure in R. Atria or R. Ventricle Increased
10
Q
The Skeletal Muscle Pump and Respiratory Pump help ____.
A
Return blood to right side of the heart.
11
Q
Are venous valves open or closed during Skeletal Pump (at rest)
A
Venous valves are open - Allowing blood to flow towards the heart.
12
Q
Which valves open/close during muscle relaxation in the Skeletal Pump.
A
After muscle relaxation, the proximal valve closes and distal valve opens.
13
Q
Two steps in Respiratory Pump
A
Inhalation, Exhalation
14
Q
Describe pressure changes in Respiratory Pump
A
Inhalation - Pressure increased in abdominal cavity (abdominal veins compressed)
Exhalation - Increase pressure in thoracic cavity pressure
15
Q
______ pressure exerted by blood on the walls of a blood vessel
A
Hydrostatic
16
Q
BP is determined by
A
Cardiac Output
Blood Volume
Vascular Resistance
17
Q
BP progressively drops as ____ increases from the left ventricle.
A
Distance
18
Q
How do negative feedback systems control blood pressure?
A
Making adjustments in: Heart Rate, Stroke Volume, Systemic Vascular Resistance, and Blood Volume.
19
Q
Cardiovascular Center is located in what part of the brain?
A
Medulla Oblongata
20
Q
Cardiovascular Center regulates what?
A
Heart Rate, Contractility, and Blood Vessel Diameter
21
Q
Cardio-Stimulatory Center: Neurons that ____ the heart.
A
Stimulate
22
Q
Cardio-Inhibitory Center: Neurons that ____ the heart
A
Inhibit
23
Q
What types of other “INPUTs” are sent to the CV Center?
A
Higher brain regions - Cerebral Cortex, Limbic System, Hypothalamus
Sensory Receptors - Proprioreceptors, Baroreceptors, Chemoreceptors
24
Q
CV Center Output:
A
Sympathetic - Impulses reach heart via cardiac accelerator nerves
Parasympathetic - Impulses along vagal nerves to heart.
25
The nervous system regulates blood pressure via _____ .
Negative Feedback Loops.
26
Two types of reflexes used in regulation of blood pressure via Nervous system?
Baroreceptor Reflexes
| Chemoreceptor Reflexes
27
Location of baroreceptors
Aorta, Internal Carotid Arteries, and other large arteries in neck and chest.
28
Two most important reflexes for Baroreceptors:
Carotid sinus reflex and Aortic Reflex
29
Carotid Sinus Reflex helps regulate blood pressure in ____
The Brain.
30
Aortic Reflex regulates ____ blood pressure
Systemic
31
How do baroreceptors sense a drop in blood pressure?
They are stretched less.
32
Baroreceptors are stretched more due to
Increase in blood pressure.
33
Chemoreceptor Reflexes monitor
Chemical composition of blood
34
Chemoreceptors are located close to ____
Baroreceptors.
35
Chemoreceptors are stimulated by
Hypoxia, acidosis, hypercapnia
36
Hormones help to ____ regulate blood pressure
Slowly
37
How do hormones regulate blood pressure?
Altering cardiac output,
| Changing systemic vascular resistance, and adjust total blood volume.
38
Renin-Angiotensin-Aldosterone (RAA) system is activated when?
Blood volume/flow decrease to kidneys. RAA increases BP by increasing water retention.
39
Sinusoids are found in?
- Liver
- Spleen
- Bone Marrow
- Lymph nodes (carry lymph, not blood)
- Many endocrine glands (adrenal glands, pituitary gland, thyroid gland for examples)
(Yes... Some tissues contain more than one type of capillary)
40
List the locations where blood travels in order.
From the heart - arteries - arterioles - capillaries - venules - veins - back to heart
41
Some parts of the body blood may pass from one capillary network into another capillary network (one region into another in high concentrations). What is this called? What are some examples?
Portal System
Examples:
- Hepatic portal circulation (liver)
- Hypophyseal portal system (pituitary)
42
What allows the liver to get “first-pass” on the blood from the stomach, spleen, pancreas, gallbladder and the mesentric (intestinal) circulation?
Hepatic Portal System
43
__________ portal system allows the liver to also clean up some of the blood before it goes into systemic circulation.
Hepatic
44
Postcapillary Venules are very small _____ that receive blood flow directly from ______ beds.
Veins, capillary
45
Walls of the smallest venules are porous allowing phagocytic WBCs to pass through to inflamed or infected tissue. What is the name of this process, and what type of venule does it apply to?
Diapedesis; Postcapillary Venules
46
How does Epinephrine/Norepinephrine help regulate BP?
EPI/NOREPI increase CO by increasing rate and force of contraction.
Causes vasocontriction in arterioles in skin and abdominal glands.
Causes vasodialation of arterioles in cardiac and skeletal muscle.
47
Antidiuretic Hormone (ADH) regulation of BP.
ADH released from hypothalmus due to dehydration or decreased blood volume.
Promotes water retention in kidneys.
Causes vasoconstriction - increase BP.
48
Atrial natriuretic peptide/hormone (ANP/ANH)
Lowers BP by causing vasodilation.
Promotes loss of salt and water in urine (Reduces BP).
49
Erythropoietin (EPO)
Released by kidneys when blood flow/oxygen is decreased
EPO stimulates production of erythrocytes in bone marrow.
EPO is a Vasoconstrictor.
50
Autoregulation of BP
Ability of tissue to automatically adjust its blood flow to match metabolic demands.
51
Oxygen demand increase in Autoregulation of BP
Vasodilator dilate the arterioles and relax precapillary sphincters = more blood.
52
Which two stimuli cause autoregulatory changes in blood flow?
Physical Changes and Vasodialating/Vasoconstricting Chemicals
53
Vasodilating Chemical types:
K, H, Lactic Acid, Adenosine, Nitric Oxide, Kinins, Histamine
54
Vasoconstricting chemical types:
Thrombaxane A2, Serotonin, endothelins
55
Two types of circulation that respond to low O2
Pulmonary and Systemic Circulation
56
How do you check circulation?
Pulse, BP
57
Pulse is
an alternate expansion and recoil of elastic arteries after each systole of left ventricle
58
Pulse is strongest ____
closer to heart
59
Pulse becomes weaker in ____ and disappears in ____.
Arterioles, capillaries
60
Common Pulse Points on the body:
```
Carotid (Neck)
Brachial (Upper Arm)
Radial (Lower Arm)
Ulnar (Lower Arm)
Femoral (Inguinal)
Popliteal (Knee)
Posterior Tibial (Ankle)
Dorsalis Pedis (Foot)
```
61
Blood Pressure (Clinical Term)
Pressure in arteries generated by L ventrical during systole and pressure remaining during diastole.
62
How is BP measured?
Using a sphygmomanometer (BP Cuff)
63
What are the sounds heard during BP measurement
First Sound - Systolic BP
| Last Sound - Diastolic
64
Define Mean Arterial Pressure (MAP)
Average blood pressure in arteries.
(Roughly 1/3) of the way between diastolic and systolic
65
Mean Arterial Pressure (MAP) equation:
MAP = Diastolic BP + ([Systolid - Diastolic BP] / 3)
66
Normal Mean Arterial Pressure Range
70-110
67
Tissue perfusion ___ as someone transitions from ____ to exercise.
Increases, Rest
68
Site of Vasodilation and Vasoconstriction during exercise:
Vasodilation: Skeletal Muscles, Heart, Lungs, Liver, Skin
Vasoconstriction: Kidneys, digestive system, and reproductive system
69
Select the blood vessels below that are unique in basic anatomical structure. ( select all that apply)
```
A. Arteries
B. Arterioles
C. Capillaries
D. Venules
E. Veins
```
C. Capillaries
| D. Venules
70
List the artery and vein wall layers from internal to external.
```
Tunica Interna (intima)
Tunica Media
Tunica Externa (adventitia)
```
71
# Choose the best discription and location of vasa vasorum.
A. Small elastic fibers, located in the surrounding tissue
B. Small nerves, located in the smooth muscle layer
C. Small vessels that transport O2 and nutrients to cells of blood vessel walls, located in the tunica externa
C. Small vessels that transport O2 and nutrients to cells of blood vessel walls, located in the tunica externa
72
What helps anchor vessels to surrounding tissue?
Tunica Externa (adventitia)
73
The tunica externa is composed primarily of?
Collagenous fibers
74
What are the two major types of arteries?
A. Connective, Vasa vasorum
B. Fibrous, Muscular
C. Elastic, Snovial
D. Muscular, Elastic
D. Muscular, Elastic
75
The primary function of Arteries is to _______ from the _____ to tissues throughout the body.
Blood, Heart
76
True or Flase there is a clear line of demarcation between elastic and muscular arteries?
False, a gradual transition from one to the other occurs.
77
Why are elastic arteries found closest to the heart?
They are capable of withstanding higher pressures.
78
List the basic types of blood vessels.
Arteries, Arterioles, Capillaries, Venules, Veins
79
What type of venule functions as significant sites of exchange of nutrients and wastes?
Postcapillary Venules
80
What two types of venules make up the most distensible elements of the entire vascular system? (I.e. Serve as reservoirs for large amounts of blood if needed; blood volume increases of 360% have been measured in these venules).
Postcapillary and Muscular Venules
81
As postcapillary venules move away from capillaries, they gain 1-2 layers of smooth muscle that become thicker walled (50-200um diameter) preventing metabolic exchange with interstitial fluid. What type of venule did this transition into?
Muscular Venules
82
What type of vessel lack internal and external elastic laminate?
Note: This type of vessel is still distensible enough to adapt to variations in volume and pressure of blood passing through them and have high capacitance (capacity to distend to store high volume of blood).
Veins
83
Blood pressure in ______ is considerably less than that of _______.
Veins; Arteries
84
Blood exits a lacerated ______ by steady oozing flow; Conversely, blood exits a lacerated ______ in spurts with the pressure of the heart beat.
Veins; Arteries
85
Many veins (especially in the ______) contain valves.
Limbs
86
What portion of the valves form cusps?
Thin folds of tunica interna (intima)
87
Cusps project into the _______ with the “cup” portion aiming toward the ________.
Lumen; Heart
88
Low blood pressure in veins allows blood to flow backwards during ventricular ________
Diastole
89
What aids in venous return by helping to prevent excessive backflow/retrograde flow and pooling?
Valves
90
Vein with thin endothelial wall, no smooth muscle.
Vascular Sinus
91
What type of vein has surrounding dense connective tissue that replaces the tunica media and tunica externa in providing support? What is an example of this type of vein?
Vascular Sinus; Coronary Sinus
92
In the _______ limbs, superficial veins are much larger than the deep veins.
In the _______ limbs, deep veins are much larger than the superficial veins.
Upper; larger
Lower; larger
93
True or False:
Some lower limb superficial veins dump directly into venae cavae and bypass deep veins.
False; the superficial veins in the upper limbs are much larger than the deep veins and some dump directly into venae cavae and bypass deep veins.
94
True or False:
Lower limb deep veins serve as principle return pathway to heart
True
95
One-way valves in penetrating vessels allow blood to pass from ________ to _________ veins, but prevent _________ flow.
Superficial; Deep; Reverse
96
Superficial veins are _____ colored lines passing under the skin. Venous blood is deep-dark ______ in color but their thin walls and the tissue of the skin absorbs ______-light wavelengths. This allows _______ light to pass through the surface to our eyes where we see them as _____.
Blue; Red; Red; Blue; Blue
97
In regards to blood distribution at rest, what percentage of blood is in:
```
_____ systemic veins and venules
_____ systemic arteries and arterioles
_____ the systemic capillaries
_____ pulmonary blood vessels
_____ the heart
```
```
64%
13%
7%
9%
7%
```
98
As systemic veins and venules hold so much blood, they become known as ________ _________? (Also, ________ _________)
Blood reservoirs; Capacitance vessels
99
What reduces the volume of blood in the blood reservoirs diverting it to where it’s needed?
Venoconstriction
100
What is the primary purpose of the cardiovascular system?
Circulate gases, nutrients, wastes and other substances to and from the cells of the body.
101
What are the 3 basic mechanisms substances enter and leave capillaries?
1. Diffusion (think concentration gradient)
2. Transcytosis (think large/awkward molecule movement)
3. Bulk Flow (think pressure gradient)
102
True or False: O2 and nutrients are usually present in arterial blood in higher concentrations than in tissue/interstitial fluid
True; Diffuses down its concentration gradient into interstitial fluid
103
True or False: CO2 and other wastes released by body cells are in higher concentration in interstitial fluid.
True; Diffuses down its concentration gradient into the blood (which then makes it venous in nature)
104
Movement down the concentration gradient is?
Diffusion
105
The following describe what type of capillaries:
- Continuous capillaries
- Very “tight” junctions
- Endothelial cells very closely packed together
- Blocks many substances from passing through this _____-_____ barrier.
Brain capillaries; blood-brain
106
What parts of the brain lack blood-brain barrier and allow capillary exchange to occur more freely?
Hypothalamus, pineal gland, and pituitary gland
107
Small quantity of material crosses capillary walls very slowly by ____________.
Transyctosis
108
Cell membrane surrounds what it wants to bring into the cell, creating a “vesicle”. What is this action called?
Endocytosis
109
Vesicle fuses with cell membrane, releases contents, becomes part of cell membrane afterward. What is this action called?
Exocytosis
110
What capillary crossing method is used for mainly large, lipid-insoluble molecules?
Transcytosis
111
How does Insulin enter the bloodstream?
Transcytosis
112
Certain antibodies (also proteins) pass from maternal circulation into fetal circulation by what process?
Transcytosis
113
What two pressure-driven mechanisms does Bulk Flow consist of?
1. Filtration
| 2. Reabsorption
114
What is the passive process by which large amount of fluid moves into and out of capillaries rapidly? This is pressure driven, not concentration.
Bulk Flow
115
What process consists of things moving against their concentration gradient because of the pressure being exerted?
Bulk Flow
116
What process is considered far more efficient than diffusion?
Bulk Flow
117
Filtration is pressure driven movement of fluid and solutes _____ blood within the __________ into __________ ___________.
From; capillaries; interstitial fluid
118
What are two pressures that promote filtration?
1. Blood hydrostatic pressure (BHP)
| 2. Interstitial fluid osmotic pressure (IFOP)
119
Reabsorption is pressure driven movement of fluid and solutes ________ the __________ __________/space into the __________
from; interstitial fluid; blood
120
What is the one main pressure that promotes reabsorption (normally)?
Blood colloid osmotic pressure (BCOP)
121
What does the following describe:
- Balance of the filtration and reabsorption pressures
- Determines whether volumes of blood and interstitial fluid remain steady or change
- Supported by Starling’s law of the capillaries
Net Filtration Pressure (NFP)
122
What is the Net Filtration Pressure (NFP) formula, and what do the acronyms mean?
NFP = (BHP + IFOP) - (BCOP + IFHP)
BHP: Blood hydrostatic pressure
IFOP: Interstitial fluid osmotic pressure
BCOP: Blood colloid osmotic pressure
IFHP: Interstitial fluid hydrostatic pressure
123
If Net Filtration Pressure (NFP) is positive, what does it promote?
Filtration
124
If Net Filtration Pressure (NFP) is negative, what does it promote?
Reabsorption
125
Tunica externa (adventitia), connective tissue composed primarily of collagenous fibers contains a ______ amount of elastic fibers.
Small
126
Small nerves that control contraction and dilation in the smooth muscle layer of vessel walls are called?
Nervi vasorum
127
What two tunica lamina are found only in arteries, not veins?
Tunica Media external elastic lamina
Tunica Interna, internal elastic lamina
128
What structures
of the vessel wall has a variable number of window like openings that facilitate diffusion of materials in both directions?
Tunica Media External Elastic Lamina (membrane)
Most external part of the Tunica Interna, internal elastic lamina (membrane)
129
The tunica media smooth muscle layer is innervated by ______ nerve fibers only.
Sympathetic
130
What does the smooth muscle layer of the tunica media regulate?
Regulates the diameter of the vessel lumen
Smooth muscle contracts/dilates for blood flow regulation as needed
131
Which layer of the vessel wall has direct contact with blood as it flows through the lumen?
Endothelium of the Tunica Interna (Intima) makes up the lumen lining the vessel wall
132
What three layers make up the Tunica Interna (Intima)?
Consists of multiple layers
1. internal elastic lamina layer (arterial)
2. basement membrane layer (arterial, venous)
3. endothelial cell layer (arterial, venous)
133
True/False the basement membrane (subendothelial layer) of the tunica Interna is permeable and provides physical support for the epithelial layer?
True
134
Von Willebrand factor
Helps platelet adhesion when needed (effects clotting)
135
Tissue plasminogen activator
Promotes fibrinolysis ( helps break up clots)
136
Thromboxane
Local vasoconstrictor; type of a prostaglandin
137
Nitric oxide
Local vasodilator
138
Prostacyclin
A local vasodilator; type of a prostaglandin
139
Endothelin
A local vasoconstrictor
140
Elastic fibers in elastic arteries allow for _____ as large volumes of blood with higher pressure are pumped into them from the ______. Once the elastic fibers expand, vessel walls _____ which promotes propelling blood forward in the system.
Expansion, Heart, Recoil
141
List some Elastic Arteries
Aorta, Pulmonary trunk/pulmonary arteries, Brachiocephalic, Subclavian, Common Carotids, Common iliacs
142
When do elastic arteries propel blood onward?
While the ventricles are in diastole
143
As blood is expelled into aorta or pulmonary trunk, the walls expand accounting for surge. What is the term for the momentary storage of mechanical energy created by the expansion of the aorta/pulmonary walls called?
Pressure reservoir
144
What are the purposes of elastic arteries?
Propel blood onward
Conduct blood from the heart to medium sized muscular arteries
145
What is another name for elastic arteries?
Conducting arteries
146
How do muscular arteries push blood forward to arterioles?
Extensive musculature instead of elastic recoil
147
Name the Artery type that is capable of greater vasoconstriction and vasodilation, helping adjust the rate of blood flow?
Muscular Arteries
148
What is the muscular artery lumen diameter range?
.1mm - 10mm
149
Which artery type has the largest lumen diameter?
Elastic Arteries
| Usually > 10mm lumen size
150
What arteries are muscular arteries?
Axillary arteries
Brachial arteries
Femoral arteries
151
Why are muscular arteries also known as distributing arteries?
They continue to branch and distribute blood to arterioles
152
What term is used to describe a union of branches of two or more vessels in the same tissue?
Anastomoses
153
______ provides alternate routes for blood to reach or leave an organ and may occur between arteries, arterioles, venules or veins.
Anastomoses
154
Will anastomoses occur between two different vessels (vein and artery)?
Not normally; arteriovenous fistula is not a normal occurance
155
When a blockage or slow flow occurs in small vessels, sometimes _______ are created. This is called collateral circulation.
Anastomoses
156
Neovascularization or angiogenesis is a product of what?
Collateral circulation (anastomoses)
157
List the differences and similarities between veins and arteries of the tunica externa (adventitia).
Arteries
●Thinner than the tunica media layer
●Collagenous and elastic fibers present
●Nervi vasorum and vasa vasorum present
```
Veins
●Normally the thickest layer
●Collagenous fibers predominate
●Some smooth muscle fibers
●Nervi vasorum and vasa vasorum present
```
158
List the differences and similarities between veins and arteries of the tunica media.
Arteries
●Normally thickest layer
●Smooth muscle cells and elastic fibers predominate
●Proportions of these vary with distance from the heart
●External elastic lamina (membrane)
●Boundary between tunica media and tunica externa
Veins
●Normally thinner than tunica externa
●Smooth muscle cells and collagenous fibers predominate
●Has nervi vasorum and vasa vasorum in this layer as well
●No external elastic lamina present
159
List the differences and similarities between veins and arteries of the tunic intima.
Arteries
●Internal elastic lamina
●Endothelial cells line this layer
●Usually appears wavy because of constriction of smooth muscle in tunica media
Veins
●Endothelial cells line this layer
●Has valves (more in lower limbs than upper)
●Thickened cusps of endothelium reinforced with connective tissue (similar to semilunar valves of heart)
●No external elastic lamina present
160
Approximately how many microscopic arterioles are their in the body?
400 million
161
What level is known as resistance vessels?
Arterioles
162
What controls the pressure going into the capillaries?
Arterioles
163
True/False capillaries are near almost every vessel in the body?
True
164
Tissues with _____ metabolic demand have more extensive capillary networks.
Higher
165
List some tissues with a higher metabolic demand with extensive capillary networks.
Muscles, brain, liver, kidneys, Nervous system
166
Approximately how many capillaries are there in a average adult?
20 billion
167
Which blood vessel is the smallest?
Capillaries
168
What layer of arterioles stays in partial contraction at all times due to sympathic stimulation?
Tunica Media
169
Resistance is due to blood components ______ againes vessels walls during vasoconstriction and vasodilation.
Rubbing
170
A change in _____ _____ causes changes to blood pressure overall
Arteriole diameter
171
How is back pressure created and where does the blood circulation travel?
When aterioles constrict, blood flow is slowed going into capillaries (down stream), creating back pressure.
This back pressure is put into systemic circulation (up stream)
172
______ are short vessels that connect arterioles to the capillary networks.
Metarterioles
173
What tightly regulates blood flow from metarteriol into capillaries?
Pre-capillary Sphincters
174
If all precapillary sphincters in the body were completely ______ at same time, very little blood would exist in arteries, arterioles, venules, veins or organs.
Open,
175
Open when the tissue they feed need oxygen or removal of waste products, then close again.
Pre-capillary Sphincters
176
When all sphincters _____, blood flows from arteriole, into metarteriole through the thoroughfare channel and then into venule
Closed
177
What tunica layer is thickest in veins?
Tunica Externa (adventitia)
178
Aside from the thickness of vein tunica externa (adventitia), what is another difference between arteries and vein adventitia?
Vein adventitia have some smooth muscle fibers mixed in with the predominantly collagenous fibers.
179
Which wall layer is the thickest for arteries?
Tunica Media
180
Proportions of these vary with distance from the heart?
Smooth muscle cells and elastic fibers
181
What is the boundary between tunica media and tunica externa(adventitia)?
External elastic lamina (membrane)
182
Usually appears wavy because of constriction of smooth muscle in tunica media.
Arteries (tunica intima)
183
What is the big difference between veins in the Tunica media/externa and veins in the Tunica Intima?
The Tunica Intima layer of veins has valves ( more in the lower limbs than upper).
184
What is the true layer that has contact with luminal contents?
Endothelium layer of the Tunica Interna (Intima)
185
What vessel wall layer proliferates to form new cells in the repair of blood vessels or the growth of new blood vessels (angiogenesis)?
Endothelium of the tunica interna (intima)
186
Elastic Arteries have other names, what are they?
Conducting Arteries and Pressure Reservoir
187
Does not have elastic recoil, relies on extensive musculature to push blood forward.
Muscular Arteries Tunica Media layer contains more smooth muscle and less elastic fibers than elastic arteries
188
What muscular arteries are known as distributing arteries?
Axillary Arteries
Brachial Arteries
Femoral Arteries
189
What arteries appear more uniformed and have a greater elasticity?
Elastic Arteries
