Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physiology1 > The Cardiovascular system > Flashcards

The Cardiovascular system Flashcards

1
Q

Factors affecting resistance

A
  1. Blood viscosity (affected by vol. and no. of erythrocytes)
  2. Total blood vessel length
  3. Blood vessel diameter (vasoconstricted=more resistance, vasodilated = less resistance)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What type of blood vessel acts as a ‘pressure reservoir’ and are near the heart?

A

Elastic/conduit arteries- they contain lots of elastin that allow them to expand and recoil as blood is ejected by the heart

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

What type of artery delivers blood to specific organs?

A

Muscular arteries- play a huge role in regulation of blood pressure

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

Define systolic and diastolic blood pressure

A

Systolic blood pressure - maximal arterial pressure reached during ventricular ejection
Diastolic blood pressure - minimum arterial pressure reached just before ventricular ejection

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

Is blood pressure higher in the systemic or pulmonary circulation?

A

Systemic circulation (heart–>body–>heart)

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

What is the term describing the difference between systolic and diastolic pressure?

A

Pulse pressure

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

What is arteriole function controlled by?

A

neural, hormonal and local chemicals

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

What is the basal level of contraction of arterioles called?

A

intrinsic tone

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

What are the 3 types of capillaries?

A
  • Continuous
  • Fenestrated
  • Sinusoidal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the 3 types of capillaries?

A
  • Continuous (skin, muscle)
  • Fenestrated (intestines, kidneys)
  • Sinusoidal (liver)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

In some tissues and organs, blood enters capillaries through ________.

A

Metarteriole

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

In some tissues and organs, blood enters capillaries through ________.

A

Metarterioles

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

Major functions of veins

A
  • Act as a low pressure reservoir

- maintain peripheral venous pressure

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

Major functions of veins

A
  • act as a low pressure conduits returning blood to the heart
  • maintain peripheral venous pressure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

define atrioventricular septum

A

the muscular wall separating the left and right ventricles

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

define pericardium

A

muscular sac enclosing the heart

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

define myocardium

A

muscular wall of the heart

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

define epicardium

A

fixes inner layer of pericardium to the heart

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

name all the valves of the heart

A
  • aortic semi-lunar valve
  • pulmonary semi-lunar valve
  • atrioventricular valves –> bicuspid and tricuspid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

function of the papillary muscles

A

do not open or close the AV valves but limit movement to prevent backflow

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

function of the chordae tendinae

A

fastens AV valves to the papillary muscles

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

function of the cardiovascular system is impacted by:

A
  • nervous system
  • endocrine system
  • kidneys
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

blood is supplied to the heart itself by ______

A

coronary arteries

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

features of skeletal muscle

A 
multi-nucleated
striated
elongated - fibre
use the sliding filament mechanism to contract
have gap junctions
large mitochondria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

features of cardiac muscle

A

single or double nucleated
striated
adjacent cells connected by intercalated disk

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

features of smooth muscle

A

single nucleus
spindle-shaped in sheet-like layers
single and multi-unit

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

node cells have the ability to stimulate their own action potentials, this is called ______

A

automaticity

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

1% of cardiac cells do not function in contraction, these cells are ____

A

the conducting system of the heart and are in electrical contact with the cardiac muscle cells via gap junctions

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

what the sympathetic nervous system innervate and what neurotransmitter does it release?

A

the entire heart and node cells

Norepinephrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what does the parasympathetic nervous system innervate and what neurotransmitter does it release?

A

node cells

acetylcholine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what type of receptors are those for acetylcholine?

A

muscarinic type

32
Q

what type of receptors are those for norepinephrine?

A

beta-adrenergic

33
Q

how is contraction conducted in the heart?

A

sinoatrial node –> atrial muscle cells –> atrioventricular node –> Bundle of His –> left and right bundle branches –> left and right purkinje fibres –> ventricular muscle cells

34
Q

how is an action potential transmitted?

A

through gap junctions between myocardial cells

35
Q

through which pathway does the wave of depolarisation travel to get to the AV node

A

internodal pathway

36
Q

why does the purkinje fibres also supply the papillary muscles?

A

it tell them to contract before the rest of the atria to help prevent backflow through the valves

37
Q

what does an ECG reading show?

A

the electrical activity not a single action potential

38
Q

P wave

A

result of the depolarization wave from the SA node to the AV node. Atria contract 0.1 seconds after the P wave starts

39
Q

QRS complex

A

is a result of ventricular depolarization and precedes ventricular contraction

40
Q

T wave

A

caused by ventricular repolarization

41
Q

define cardiac output

A

the product of heart rate and stroke volume

CO= HR X SV

units L/min

42
Q

define stroke volume

A

the difference between end diastolic volume and end systolic volume
SV = EDV - ESV

43
Q

what do positive chronotropic factors do?

A

increase heart rate

44
Q

what do negative chronotropic factors do?

A

decrease heart rate

45
Q

which nervous system increases heart rate?

A

sympathetic nervous system

46
Q

What is the Frank-Starling mechanism?

A

the relationship between stroke volume and end-diastolic volume

The ventricle contracts more
forcefully during systole when it has been filled to a greater degree during diastole (stroke volume increases as end-diastolic volume increases)

47
Q

what accounts for the Frank-Starling mechanism?

A

a length-tension relationship because end-diastolic volume is a major determinant of how stretched the ventricular sarcomeres are just before contraction

increase end-diastolic volume, increase ventricular sarcomere stretching, increase contractile force generated, increases stroke volume

48
Q

what is the significance of the Frank-Starling mechanism?

A

maintains the equality of left and right cardiac outputs

If venous return is increases, end-diastolic volume increases so stroke volume increases to match the cardiac output of the other ventricle

49
Q

define ventricular contractility

A

the strength of a contraction at any given end-diastolic volume

50
Q

how is ventricular contraction increased?

A

The sympathetic nervous system is stimulated to increase norepinephrine secretion, which acts on beta-adrenergic receptors to increases ventricular contraction

plasma epinephrine acting on these receptors also increases contractility

51
Q

what is the effect of increased contractility?

A

results in greater stroke volume due to a more complete ejection of the end-diastolic volume

52
Q

what is heart rate dependent on?

A
  • choronotropic factors
  • sympathetic nervous system
  • parasympathetic nervous system
53
Q

what is stroke vol. dependent on?

A

end diastolic volume and end systolic volume

dependent on frank starling mechanism and contractility

54
Q

what is cardiac output dependent on?

A

stroke volume and heart rate

55
Q

what is total peripheral resistance and what is it dependent on?

A

total resistance to flow in systemic blood vessels from beginning of aorta to ends of venae cavae

vasculature

56
Q

arterial baroreceptors, eg aortic arch baroreceptor, respond to changes in?

A

arterial pressure

they are sensory neurons highly sensitive to stretch or distortion

degree of stretch directly proportional to blood pressure

57
Q

in term of baroreceptors, what happens if arterial pressure increases?

A

baroreceptor firing increases, this decreases sympathetic outflow to the heart, arterioles and veins and increases parasympathetic outflow to heart

58
Q

what happens if arterial pressure decreases?

A

decrease in baroreceptor firing, increase in sympathetic outflow, decreases parasympathetic outflow to the heart

plasma concentration of angiotensin II and vasopressin increases which increases arterial pressure by constricting arterioles

59
Q

what is the medullary cardiovascular center

A

a network of connected neurons in the medulla oblongata that act as the primary integrating center for the baroreceptor reflexes

60
Q

how to adjust arterial pressure long term?

A

change blood volume

61
Q

how to calculate mean arterial pressure

A

diastolic pressure + 1/3 (systolic pressure - diastolic pressure)

62
Q

how does increased arterial pressure decrease blood vol.?

A

increases urinary loss of sodium and water, therefore decreases plasma vol.

63
Q

define hypertension

A

chronically increased systemic arterial pressure

64
Q

methods of treating hypertension?

A
  • diuretics
  • beta-adrenergic receptor blockers
  • calcium channel blockers
  • angiotensin-converting enzyme inhibitors
65
Q

function of diuretics

A

increase excretion of sodium and
water, decreasing cardiac output with no
change in peripheral resistance

66
Q

function of beta-adrenergic receptor blockers

A

reduce cardiac output

67
Q

function of calcium channel blockers

A

Reduce entry of
calcium in vascular smooth muscle cells =
weaker contractions (vasodilation) = lowers peripheral
resistance

68
Q

function of angiotensin-converting enzyme inhibitors

A

: Final step in formation of
Angiotensin II (a vasoconstrictor) is mediated
by an ACE. Blocking this enzyme causes
vasodilation lowering peripheral resistance

69
Q

function of aldosterone

A

slow-acting steroid hormone that stimulates sodium reabsorption by kidney tubules

70
Q

what controls aldosterone secretion?

A

angiotensin II

71
Q

how does the renin-angiotensin system work to respond to changes in NaCl conc

A

intra-renal baroreceptors detect changes in stretching due to lower blood volume. This stimulates the production of renin which works to split angiotensin I from angiotensinogen. Angiotensin I is converted to angiotensin II which stimulates aldosterone secretion, which stimulates sodium reabsorption by kidney tubules. Therefore increasing plasma volume and blood volume.

72
Q

where are angiotensin-converting enzymes found?

A

on endothelial cells

73
Q

what is the vasopressin?

A

rapid acting peptide produced by the pituitary gland

which stimulates water reabsorption

74
Q

what is atrial natriuretic peptide (ANP) and what does it do?

A

produced by cardiac cells to inhibit sodium reabsorption by kidney tubular cells
acts on renal blood vessels to increases filtration rate causing sodium excretion
inhibits the action of aldosterone

75
Q

what happens within hours of blood loss?

A

Compensatory movement of
interstitial fluid into the capillaries
to increase plasma volume
REDISTRIBUTION NOT REPLACEMENT

Other slower effects include:

  • an increase in thirst
  • a decrease in salt and water excretion

Mediated by hormones and kidney function:
- renin, angiotensin and aldosterone

76
Q

what happens within days of blood loss?

A

cells are replaced by erythropoiesis and haematopoiesis

Physiology1 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions