Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

BRS Y1 > Week 8- Control of Heart Function > Flashcards

Week 8- Control of Heart Function Flashcards

1
Q

What is the medical term for increased heart rate?

A

Chronotrophy

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

What is the medical term for increased force of contraction?

A

Inotrophy

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

What nervous system affects the kidneys?

A

Sympathetic

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

What happens when theres reduced baroreceptor firing?

A

Increases sympathetic nerve activity

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

What happens when theres increased baroreceptor firing?

A

Reduced SNS activity

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

What makes up the arterial circuit

A

Aortic arch
Carotid sinus
Afferent arterioles of the kidneys

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

What receptors are associated with changes in sympathetic nervous system activity?

A

Baroreceptors

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

What 2 locations does parasympathetic stimulation arise from?

A

Cranial part of spinal chord

Sacral part of spinal chord

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

What 2 locations does sympathetic stimulation arise from?

A

Thoracic vertebra

Lumbar vertebra

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

What pre and post ganglionic neurotransmitters does the parasympathetic nervous system use?

A

Pre: Ach
Post: Ach

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

What pre and post ganglionic neurotransmitters does the sympathetic nervous system use?

A

Pre: Ach
Post: NA

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

In controlling the heart function, what role does the parasympathetic nervous system play?

A

Controlling the heart rate

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

In controlling the heart function, what role does the sympathetic nervous system play?

A

Controlling circulation

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

What receptors does the sympathetic nervous system activate?

A

Beta 1

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

What does the activation of beta 1 receptors in the heart do?

A

Activates cyclic AMP which increases heart rate

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

Where does nervous stimulation go to in the heart?

A

SAN

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

Under tonic (restful) conditions which branch of the nervous system is more active?

A

Parasympathetic

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

How do sympathetic nerves increase blood volume in the kidney?

A

They decrease glomerular filtration, decreasing sodium secretion increasing blood vol

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

In the renal system what do sympathetic nerve fibers innervate?

A

Afferent and efferent arterioles of the glomerulus

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

What is the primary sight of sympathetic activity in the kidneys?

A

Afferent arterioles

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

What receptors do sympathetic nerves act on in the kidneys? What effect does this have?

A

Alpha 1 receptors, causes vasoconstriction, reduces glomerular filtration rate and reduces sodium filtered

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

What cells are the site of synthesis, storage and release of renin?

A

Juxtaglomerular cells

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

What receptor allows renin secretion?

A

Beta 1 adrenoreceptor

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

What local mediators cause vasodilation?

A

Nitric oxide

Prostacyclin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What local mediators cause vasoconstriction?
Thromboxane A2 | Endothelins
26
What systemic mediators cause vasoconstriction?
Vasopressin Noradrenaline/adrenaline Angiotensin II
27
What systemic mediators cause vasodilation?
Kinin | Atrial natriuretic peptide (ANPs)
28
What 4 factors affect venous pressure?
Blood vol SNS activation of veins Skeletal muscle pumping Respiratory movement
29
What affects atrial pressure?
Venous return
30
What effects venous return?
Venous pressure
31
Whats the main pacemaker of the heart?
SAN
32
What is the nerve involved with the parasympathetic control of the heart?
Vagus
33
What does the parasympathetic nervous system do to the heart? What phase does it specifically affect and how?
Slows down the heart rate and decreases the slope of phase 4
34
What does the sympathetic nervous system do to the heart? What phase does it specifically affect and how?
Increases the heart rate and increases the slope of phase 4
35
What receptors detect blood volume?
Venous volume receptors
36
How do venous volume receptors increase blood pressure?
They increases renin secretion, which increases angiotensin II production, leading to vasoconstriction and increased blood pressure
37
What sensors are present in the cardiopulmonary circuit?
Volume sensors
38
What sensors are present in the arterial circuit?
Pressure sensors
39
Where is the vasomotor centre located?
Bilaterally in the reticular substance of the medulla and lower third of the pons
40
What comprises the vasomotor centre?
``` Vasoconstrictor area (pressor) Vasodilator area (depressor) Cardio-regulatory inhibitory area ```
41
What does the lateral portion of the VMC do to heart activity?
Influences heart rate and contractility
42
What does the medial portion of the VMC do to heart activity?
Signals via vagus nerve to decrease heart rate
43
How is the VMC influenced?
By higher centres in the brain which have excitatory or inhibitory effects on it
44
How does the VMC transmit impulses and to where?
Distally through the spinal chord to almost all blood vessels
45
How is blood pressure detected in the kidneys?
By arterial baroreceptors
46
What is venous volume distribution affected by?
Peripheral venous tone, gravity, skeletal muscle pump and breathing
47
What determines the amount of blood flowing back to the heart?
Central venous pressure (mean pressure in the right atrium)
48
How does venous constriction affect compliance and venous return?
Decreases compliance | Reduces venous return
49
In arterioles what does constriction determine?
Bloodflow to downstream organs Mean arterial blood pressure The pattern of blood flow to organs
50
How do local and systemic mechanisms of regulating blood flow differ in terms of their relation to smooth muscle?
Local mechanisms are intrinsic to smooth muscle | Systemic mechanisms are extrinsic to smooth muscle
51
How do local and systemic mechanisms of regulating blood flow differ in terms of their mediators?
Local mechanisms use endothelium derived mediators | Systemic mechanisms use non endothelium derived mediators
52
What are local mechanisms important for in the regulation of blood flow?
Reflex local blood flow regulation
53
Describe action potentials of the AVN
They are slow and calcium mediated
54
What is found at the base of the right atrium?
Triangle of Koch
55
How long is the cardiac action potential compared to normal action potentials?
200-300 ms compared to the usual 2-3ms
56
What are the 5 phases of the cardiac action potential?
``` Phase 0: upstroke Phase 1: early repolarisation Phase 2: plateau Phase 3: repolarisation Phase 4: resting membrane potential ```
57
What is the absolute refractory period?
The time period where no action potential can be initiated
58
What is the relative refractory period?
The time period where an action potential can be generated but only with strong stimulus
59
What is the resting membrane potential determined by?
K+ efflux
60
What is the upstroke determined by?
A large increase in the membrane permeability to sodium
61
Why do different parts of the heart have different action potential shapes?
They have different ion currents flowing and different ion channel expression
62
What phases are missed out of the SAN action potential?
Phase 1 and 2 (early repolarisation and plateau)
63
What type of calcium channels does the SAN have?
T type (T= transient aka faster)
64
What does the L in L type channels stand for?
Latent (slow)
65
What is the funny current of the SAN?
Flow of sodium current that causes phase 4
66
What activates phase 4 of the SAN?
Cyclic AMP

BRS Y1 (52 decks)

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