Lecture 16-17 Flashcards

1
Q

What is the function of arteries?

A

Transport of oxygenated blood

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

What is the function of arterioles?

A

Act as valves for entry into capillaries

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

What is the function of capillaries?

A

Gas and nutrient exchange

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

What is the function of venules

A

Collects blood from capillary

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

What is the function of Veins?

A

Carry deoxygenated blood back to the heart

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

What are the layers of arteries?

A
Tunica interna (intima)
Tunica media
Tunica externa
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the 3 components of the tunica interna (intima)?

A

Endothelium
Basement membrane
Internal elastic lamina

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

Dennis, T or F? Tunica interna of the veins contains lining of simple squamous epithelium (endothelium), basement membrane, and layer of elastic tissue (internal elastic lamina).

A

False, Tunica interna of the arteries, not veins.

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

The ____ _____ is the thickest middle layer of the arteries that consists of elastic fibers and smooth muscle that extend circularly around the lumen.

A

Tunica media

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

Which layer of the arteries consists mainly of elastic and collagen fibers?

A

Tunica externa

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

T or F? In muscular arteries, an external elastic lamina composed of elastic tissue separates the tunica externa form the tunica media

A

True

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

Which type of arteries are capable of greater vasoconstriction and vasodilation to adjust blood flow.

A

Muscular

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

T or F? The aorta is a muscular artery with the largest diameter.

A

False, it is an elastic artery

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

The _____ innervates the smooth muscle in the tunica media.

A

SNS (Making the muscular arteries capable of greater vasoconstriction and vasodialation to adjust blood flow.

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

T or F? Normally, Endothelium is the only tissue that contacts blood.

A

True

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

T or F? Capillaries contain smooth muscle so they can perform vasoconstriction and vasodilation.

A

False, they DO NOT contain smooth muscle, so they CANNOT perform vasoconstriction or vasodilation.

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

T or F? Veins consist of the same 3 tunics as arteries but with more elastic tissue and smooth muscle than arteries.

A

False, less elastic tissue and smooth muscle

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

Veins are much more ________ than arteries which allows them to hold more blood and act as a reservoir.

A

compliant

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

_____ contains valves to prevent backflow of blood.

A

Veins

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

How is Cardiac Output (CO/Q) calculated?

A
CO = MAP / TPR
CO = HR x SV
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Blood flows through the body due to a ____ _____.

A

Pressure gradient

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

What is normal mean artery pressure?

A

Mean (MAP) = DBP + 1/3(SBP-DBP) = 93 mmHg
Diastolic = 80 mmHg
Systolic = 120 mmHg

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

How is Mean Arterial Pressure calculated (MAP)?

A
MAP = CO x TPR
MAP = DBP + 1/3(SBP-DBP)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

T or F? MAP represents the average arterial pressure during a single cardiac cycle.

A

True (average 93 mmHg [aorta])

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

_______ also represents the pressure gradient in the systemic circulation since the pressure in the right atrium is nearly 0 mmHg.

A

MAP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the mean pressure of the capillaries?

A

17 mmHg (mean)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the pressure gradient of veins and the right atrium?

A

0 mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the major driving force blood flow through the systemic circulation?

A

MAP which represents the pressure gradient.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

T or F? Pulmonary circulation is a low pressure system.

A

True

30
Q

What is the pressure range for pulmonary artery and capillaries?

A

Pulmonary artery = 8-25 mmHg

Capillaries = 7 mmHg

31
Q

In the capillary beds, when the sphincters contract, blow flows through the _____ ______.

A

Thoroughfare channel

32
Q

How is pulse pressure calculated?

A

Pulse pressure = SBP-DBP

33
Q

What factors affect pulse pressure?

A

Stroke volume

Compliance

34
Q

Greater _______ volume results in greater pressure rise with each heart beat.

A

stroke

35
Q

T or F? Lower compliance of artery results in a greater pressure rise with every beat

A

true

36
Q

What 2 factors directly affect CO/Q?

A
Heart rate (HR)
Stroke Volume (SV)
37
Q

What factor directly affect heart rate (HR)?

A

SNS and PNS

38
Q

What factor directly affect stroke volume (SV)?

A

Strength of contraction
(SNS - contractility)
(EDV - preload)

39
Q

What factor affect End Diastolic Volume (EDV)?

A

Venous Return

40
Q

What factors directly affect venous return?

A

Blood volume
Venous pump
Respiratory pump
Venous tone

41
Q

What factors directly affect blood volume?

A

RAAS (Renin-angiotensin-aldosteron system)
ANP (Atrial natriuretic peptide (factor, ANF)
ADH (Anti-diuretic hormone)

42
Q

What is systemic vascular resistance SVR?

A

Aka Total peripheral resistance (TPR) which is the resistance to blood flow through all of the vasculatures in the body

43
Q

T or F? Veins are less compliant than arteries.

A

False, more compliant

44
Q

What factor directly affect TPR?

A

Diameter of arterial vessel

45
Q

What factors directly affect the diameter of an arterial vessel?

A

SNS
RAAS (Renin-angiotensin-aldosterone system)
ANP (Atrial natriuretic peptide (factor, ANF)
ADH (Anti-diuretic hormone)

46
Q

Rhythmic contraction of skeletal muscle helps to push blood in the veins towards the heart, this describes the ____ _____

A

Venous pump; this increases venous return

47
Q

During inspiration, abdominal pressure increases and intrathoracic pressure decreases, this describes the _______ ______

A

Respiratory pump; this increases venous return

48
Q

T or F? Venous tone refers to the venoconstriction and venodilation

A

True; Venoconstriction increases venous tone and Venodilation decreases venous tone

49
Q

T or F? Activation of the RAAS increases blood pressure.

A

True

50
Q

What is renin substrate and where is it secreted from?

A

AKA angiotensinogen and is secreted from the liver

51
Q

T or F? The RAAS actives when the arterial pressure deviates (increases or decreases) from normal pressure ranges.

A

False, only activates when arterial pressure decreases.

52
Q

What converts Angiotensin I to Angiotensin II?

A

Angiotensin-converting enzyme (ACE prominent in capillary wall of the lungs)

53
Q

What does angiotensin II directly affect?

A
Stimulates SNS
Aldosterone Increase (causes renal retention of salt/water)
Renal retention of salt/water
Vasoconstriction
Inhibit renin release from kidneys
54
Q

Where is vasopressin released?

A

Vasopressin aka Anti-diuretic hormone (ADH) is released from the posterior pituitary gland.

55
Q

T or F? ADH increases blood pressure by vasoconstriction and promotes kidney reabsorption of water and salt.

A

False, all true except does not promote salt absorption.

56
Q

What are the 3 ADH receptors?

A

V1a - mediate vasoconstriction effects
V1b
V2 - mediate antidiuretic effect in kidney

57
Q

What is released by the cells of the atria in response to increased stretch (volume)?

A

Atrial natriuretic peptide (factor), ANP (ANF)

58
Q

What does ANP promote?

A

Lowering of blood pressure by

  1. Vasodilation
  2. Acts on kidneys promoting loss of salt and water in urine
  3. Suppresses secretion renin, aldosterone, and ADH
59
Q

What does ANP promote?

A

Lowering of blood pressure by

  1. Vasodilation
  2. Acts on kidneys promoting loss of salt and water in urine
  3. Suppresses secretion renin, aldosterone, and ADH
60
Q

What is release by the ventricles in response to pressure & volume overload?

A

Brain Natriuretic Peptide (Factor)(BNP or BNF); functions similar to ANP (ANF) to decrease blood volume.

61
Q

The SNS innervates most vessels except?

A

Capillaries, precapillary sphincters, and metarterioles.

62
Q

What are the type of receptors the SNS innervates to cause constriction of most vessels?

A

Alpha-1 adrenergic receptors

63
Q

Which systems are spared the vasoconstrictor effect of the SNS?

A

Coronary and cerebral systems because they both have poor vasoconstrictor innervations.

64
Q

T or F? The SNS only causes vasoconstriction.

A

False, low concentration of epinephrine binds to B2 receptors causing vasodilation.

65
Q

How does the SNS act on the heart?

A

SNS directly increases heart rate and contractility

66
Q

T or F? Majority of blood vessels are NOT innervated by PNS.

A

True

67
Q

How does the PNS act on the heart?

A

PNS directly decreases heart rate and contractility

68
Q

What regulates the ANS?

A

Vasomotor center by means of signals sent by receptors (Baroreceptors, Chemoreceptors, and Atrial/Pulmonary stretch receptors)

69
Q

Where are baroreceptors located?

A

Baroreceptors are stretch receptors located in walls of large arteries (carotid artery and aortic arch)

70
Q

How does an increase or decrease in baroreceptor stretch affect TPR and CO?

A

Increase stretch would increase firing rate (more action potential) and increase PNS and decrease SNS. Oppositely for decrease stretch.

71
Q

Chemoreceptors located in the carotid and aortic bodies sense decrease in ___ content and an increase in _____ and ____ content.

A

O2; CO2; H+; As blood pressure decreases, blood flow decreases through chemoreceptors. Chemoreceptor becomes stimulated and excites vasomotor center resulting in increased blood pressure.

72
Q

Which receptor is important in minimizing changes in pressure in response to volume changes?

A

Low-pressure receptors (Atria/Pulmonary stretch receptors)