Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Physiology 215 > Module 6: Vascular Physiology > Flashcards

Module 6: Vascular Physiology Flashcards

1
Q

T/F
Flow is proportional to the pressure gradient

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

T/F
Flow is proportional to resistance

A

False
It’s inversely proportional

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Within the circulatory system, where is blood pressure the highest?

A

In the aorta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How is a pressure gradient formed?

A

As blood travels from the aorta to the rest of the body, the friction between the blood and blood vessel causes a decrease in pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 3 factors that contribute to blood flow

A

The viscosity of the blood
Vessel length
Vessel radius

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How does the viscosity of the blood contribute to blood flow?

A

The thicker the blood, the higher the frictional forces and therefore the resistance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How does the length of the vessel contribute to blood flow?

A

At a constant radius, a longer vessel has higher resistance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How does vessel radius impact blood flow?

A

Smaller radius creates more resistance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the 5 components to the vascular tree?

A

Systemic arteries
Arterioles
Capillaries
Venules
Systemic veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

T/F
The pulmonary system receives 80% of cardiac output

A

WRONG
It receives 100% bc all of the blood coming out of the right ventricle goes here

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the 3 layers of a blood vessel?

A

The inner layer
The middle layer
The outer layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe the structure of the inner layer of a blood vessel

A

Composed of a single layer of endothelial cells surrounded by a basement membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the structure of the middle layer of a blood vessel

A

Made up of circular arrangements of smooth muscle cells and CT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the structure of the outer layer of a blood vessel

A

Made of collagen-rich CT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Where is elastic fibre found in blood vessels

A

Between the outer and middle layer and the middle and inner layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

T/F
Maximum blood pressure occurs during systole

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the systolic pressure in a healthy person?

A

120mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is passive recoil?

A

The un-stretching of the arteries that create a squeezing effect on the blood to keep arterial pressure higher

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

When does passive recoil occur?

A

During diastole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the normal diastolic pressure in a healthy person?

A

80mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

By what device is blood pressure measured?

A

By a sphygmomanometer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

The sounds of blood flowing through blood pressure monitoring are called what?

A

Korotkoff sounds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

When is the first kortkoff sound heard? What does this represent?

A

Occurs when cuff pressure is between 120-80mmHg
Represents peak systolic pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

When is the last kortkoff sounds heard? What does this represent?

A

Occurs when cuff pressure is less than 80mmHg
represents minimum diastolic pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is pulse pressure?
The difference between the systolic and diastolic pressures
26
What is mean arterial pressure (MAP)
The average pressure during the cardiac cycle
27
Large pressure swings occur where in the cardiovascular system?
In the ventricles during each heartbeat
28
Blood pressure steadily drops from the ___ to the ___ and ______
capillaries to the venules and large veins
29
How do arteriole walls differ from the walls in arteries?
They lack the high collagen content and elastin Are also much smaller in size
30
What part of the circulatory system is deemed the "resistance vessels of the circulatory system"
The arterioles
31
T/F Arteriolar resistance (total peripheral resistance) is not a constant value. Why?
True! Because arterioles are very dynamic in the regulation of their radius
32
What is shunting
The decrease in arteriole radius in the digestive system to allow blood to go to different organs
33
Describe vasoconstriction
Occurs when arterioles contract and their radius becomes smaller Increases pressure Decreases blood flow
34
Describe vasodilation
Occurs when arterioles relax and radius increases Decreases pressure Increases blood flow
35
What is vascular tone?
The state of partial constriction in arterioles
36
Why is vascular tone important?
Allows the arterioles to either dilate or constrict as necessary
37
Intrinsic control can either be:
chemical or physical
38
Extrinsic control can either be:
neural or hormonal
39
List the local chemical influences that can lead to vasodilation (7)
Decreased oxygen Increased carbon dioxide Increased acid Adenosine release Increased potassium Increased osmolarity Prostaglandin release
40
T/F Chemical influences act directly on the smooth muscle cells
False They trigger the endothelial cells to release chemical messengers that act directly on the smooth muscle cells
41
T/F Histamine causes vasodilation
True
42
What are the local physical influences of blood vessels
Temperature Shear stress Myogenic response to stretch
43
How does temperature influence blood vessel dilation/constriction?
Applying heat can cause vasodilation Applying cold can cause vasoconstriction
44
How does shear stress influence blood vessel dilation/constriction?
Increase in shear stress cause friction, which causes a release of nitric oxide to create vasodilation within the vessel to cause a reduction in the shear stress
45
How does myogenic response to stretch influence blood vessel dilation/constriction?
When smooth muscle cells are passively stretched, their myogenic response causes vasoconstriction to oppose this stretch The opposite is true if there is less stretch in the smooth muscle
46
T/F Chemical and physical influences often work at the same time
True
47
T/F Arteriolar smooth muscle is dual innervated
False It's only innervated by the sympathetic nervous system
48
Increasing sympathetic activity does what to arteriolar tone?
Increases it
49
Decreasing sympathetic activity does what to arteriolar tone?
Decreases it
50
How does hormonal input cause arteriolar contraction?
The sympathetic nerves release norepinephrine, which bind to a1-adrenergic receptors that allow increased calcium entry into the smooth muscle
51
T/F norepinephrine release does not impact the arterioles in the brain
true
52
How do you calculate mean arterial pressure (MAP)?
Total peripheral resistance (TPR) * cardiac output (CO)
53
T/F Vasopressin and Angiotensin II are vasoconstrictors
True
54
What are the walls of capillaries made of?
A single layer of endohelial cells
55
Exchange across the capillaries in all parts of the body (excluding brain) occur by what?
Diffusion
56
In the brain, exchange occurs through what? Why?
carrier-mediated transport due to the blood-brain barrier
57
What factors make capillaries ideal for diffusion?
Short distance between them and other cells Large surface area (provides many sites for exchange) Slow velocity of blood (allows for more time for exchange)
58
What are capillary beds?
Branching networks of capillaries
59
What is the purpose of a metarteriole
To provide a bypass between the arterioles and venules
60
What is the function of precapillary sphincters?
To control the flow of blood through a capillary bed
61
When the precapillary sphincter is relaxed, how is blood flow act?
Blood flows through the metarteriole and entire capillary bed
62
When the precapillary sphincter is contracted, how is blood flow affected?
Blood only flows through the metarteriole, bypassing the capillary bed
63
What is bulk flow?
The movement of protein-free plasma from the capillary lumen into the interstitial space Is the summation of filtration and reabsorption
64
What is filtration? When does it occur?
Fluids are forced out of the capillaries Occurs when outward forces are greater than inward forces
65
What is reabsorption? When does it occur?
Fluid is forced into the capillaries Occurs when inward forces are greater than outward forces
66
What forces contribute to bulk flow? (4) (good luck w this one. hard)
Capillary blood pressure Interstitial fluid colloid osmotic pressure Interstitial fluid hydrostatic pressure Plasma colloid osmotic pressure
67
What is capillary blood pressure?
The hydrostatic pressure exerted by the blood on the capillary walls that try to force fluid out of the capillary
68
What is interstitial fluid colloid osmotic pressure?
The osmotic pressure created by the presence of proteins in the interstitial fluid.
69
What forces of bulk flow want to push fluid out of the capillary?
Capillary blood pressure and interstitial fluid colloid osmotic pressure
70
What forces of bulk flow want to move fluid into the capillary?
Interstitial fluid hydrostatic pressure and plasma colloid osmotic pressure
71
What is interstitial fluid hydrostatic pressure?
The hydrostatic pressure exerted on the outside of the capillary by fluids in the interstitial space
72
What is the plasma colloid osmotic pressure?
The presence of protein in the plasma creating an osmotic pressure that tries to bring fluid into the capillary lumen
73
T/F Interstitial fluid colloid osmotic pressure is usually at 0mmHg
True
74
T/F In a normal, healthy individual, there is balance between filtration and reabsorption
False In a healthy individual, there is an imbalance
75
What does the lymphatic system consist of?
The spleen, thymus, lymph nodes, lymph channels and tonsils
76
What are the functions of the lymphatic system (4) ?
Return of excess fluid Defense against disease Transport of absorbed fat Return of filtered proteins
77
How does the lymphatic system create a defence against disease?
Lymph passes by lymph nodes on its way to the heart, which contain phagocytes and lymphocytes
78
T/F Venules generate little resistance to blood flow
True
79
Decreasing venous capacity does what to blood circulation?
Increases the amount of blood circulating
80
Increasing venous capacity does what to blood circulation?
Decreases the amount of blood circulating
81
What factors affect venous return (6)?
Sympathetic activity The skeletal muscle pump Gravity Venous valves Respiratory activity Cardiac suction
82
How does sympathetic activity impact venous return?
Increasing sympathetic activity decreases venous capacity, therefore increases venous return
83
How does the skeletal muscle pump impact venous return?
When the skeletal muscle pump is being actively used, the veins are compressed by the skeletal muscles contracting; reducing venous capacity and increasing venous return
84
How does gravity affect venous return?
When laying down, there is less hydrostatic pressure, making venous return greater When standing, the veins must fight gravity and the greater hydrostatic pressure, therefore increasing venous capacity and decreasing venous return
85
How do venous valves affect venous return?
Help to reduce hydrostatic pressure when standing, therefore increase venous return
86
How does respiratory activity affect venous return?
Increases venous return by increasing the pressure gradient between the venules and the heart
87
How does cardiac suction affect venous return?
The rapid expansion of the ventricular walls creates a suction effect during ventricular relaxation than even affects the atria, allowing for the atria to suck in blood, therefore increasing venous return
88
What is the function of baroreceptors?
To initiate a response that will return MAP back to its homeostatic set point
89
Where are baroreceptors located?
In the carotid sinus and aortic arch
90
If mean arterial pressure in increased, what happens to the baroreceptor's firing rate?
It increases
91
If MAP decreases, what happens to the baroreceptor's firing rate?
It decreases
92
Where is the cardiovascular control centre located?
In the medulla
93
What is hypertension?
Chronic high blood pressure levels
94
What is the most common type of hypertension?
Primary hypertension
95
T/F Hypertension progression can be slowed through medication
False Medication can help normalize MAP, but the disease will still progress
96
Describe secondary hypertension
The cause of hypertension is secondary to another problem

Physiology 215 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions