Brainscape's Knowledge GenomeTM

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


See full index

Circulation and Respiration > Week 1: Tuesday > Flashcards

Week 1: Tuesday Flashcards

1
Q

what does the autonomic nervous system do

A
  • innervates viscera - unconscious control
  • mediates homeostasis
  • visceral sensory and visceral motor neurons that function in visceral reflexes
  • takes 2 motor neurons in series to innervate organs
  • parasympathetic and sympathetic
  • dual innervation of organs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is homeostasis

A

maintenace of critical physiological parameters of the internal environment within the limits comparible with life

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

what are the functions of the parasympathetic divistion

A
  • conserves and restores energy reserves (anabolic)
  • promotes digestion, absorption, and storage
  • protective - miosis - contriction of pupil
  • rest and digest
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

where does the parasympathetic nervous system originate

A
  • from a restricted part of brain and spinal cord (cranial-sacral)
  • has own set of peripheral ganglia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are the functions of the sympathetic division

A
  • prepares body for action
  • mobilizes energy stores (catabolic)
  • mediates responses to stress
  • fight or flight
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

where does the sympathetic nervous system originate

A
  • from restricted part of spinal cord (thoracolumbar)
  • has own set of peripheral ganglia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is dual innervation

A
  • many organs have a sympathetic and a parasympathetic innervation (one excites and other inhibits)
  • some organs don’t (skin, sweat glands, arrector pili muscle, vascular smooth muscle, adrenal gland and adipose tissue) - only sympathetic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

resting membrane potential

A
  • net negative charge inside the cell membrane
  • ion pumps maintain concentration gradient
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what are contractile cardiac cells

A
  • generate force
  • not autorhythmic, but do conduct action potentials
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what are autorhythmic cardiac cells

A
  • provide a pathway for spreading excitation through the heart (pacemaker cells, conduction fibers)
  • don’t generate much contractile force
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what are fast-response action potentials

A
  • contractile cardiac cells
  • Na+ driven (fast Na+ channels)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what are slow-response action potentials

A
  • autorhythmic cardiac cells
  • Ca2+ driven (L-type Ca2+ channels)
  • pacemaker potentials lead to spontanous action potentials
  • due to hyperpolarization-activated cyclic nuceotide-gated (HCN) channels (funny current) and T-type calcium channels
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are the 3 steps in action potentials in contractile cardiac cells

A
  1. rapid depolarization
  2. plateau
  3. repolarization
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what are the 6 important membrane currents in contractile cardiac cells

A
  1. INa: sodium current
  2. ICa: L-type Ca current
  3. Ito: transient outward K current
  4. IKr: rapidly activated delayed rectifying K current
  5. IKs: slowly activating delayed rectifying K current
  6. IK1: inward rectifying K current
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what membrane currents are in phase 4 of autorhythmic cells

A
  • If: funny current, HCN channel
  • ICa2+ (T): T-type voltage gated channel
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what membrane currents are in phase 0 of autorhythmic cells

A

ICa2+ (L): L-type voltage gated channel

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

what phases are absent in autorhythmic cells

A

phase 1 and 2

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

what membrane currents are in phase 3 of autorhythic cells

A

IK: potassium current, dlayed rectifier potassium

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

what membrane current is important for parasympathetic regulation of HR

A

IKACh: rectifying potassium current

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

what happens at intercalated disks

A
  • desmosomes provide structural strength
  • cells linked by gap junctions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what do gap junctions allow the cell to behave as

A

a functional syncytium

22
Q

during a heartbeat where is the first action potential initiated

A

the SA node

23
Q

what is the AV node

A

the only pathway through which the signal can pass between the atria and ventricles

slight delay from SA to AV node

24
Q

why is there a delay between the SA and AV node

A

reduction of gap junctions and reduction of diamter of cells

25
Q

what does the delay allow

A

allows the heart to be “topped off”by the atrial contractions

26
Q

what does the AV node provide

A

unidirectional passage of action potential through the atria to ventricles

27
Q

what can the AV node act as if needed

A

an auxiliary pacemaker

28
Q

if any pacemaker/conduction cell can initiate its own action potential, then why is the SA node the heart’s pacemaker

A

because of the hierarchy of normal automaticity (inate firing rate) and the concept of overdrive suppression

29
Q

what is tachycardia

A

abnormally high heart rate (based on site of origin)

30
Q

what is bradycardia

A

abnormally low heart rate

31
Q

what is sick sinus syndrome

A

dysfunction of the SA node

32
Q

what is afterdepolarizations

A

depolarizations during the refractory period
* eary afterdepolarizations (phase 2-3)
* delayed afterdepolarizations (phase 4)

33
Q

what is a block

A

a conduction pathway is blocked from transmitting the action potential

34
Q

what is a block caused by

A
  • trauma
  • toxins
  • infections
  • heart defects
35
Q

what is a third degree block

A
  • a complete block
  • no atrial action potentials conducted to ventricles
36
Q

what is a second degree block and the two types

A
  • some atrial action potentials conducted to ventricles
  • type one: time from atria to ventricular depolarization gets longer and skip happens
  • type two: delay in communication but delayis random
37
Q

what is a first degree block

A
  • all atrial action potential transmitted to ventricles
  • delay at the AV node is abnormally long
38
Q

what is reentry

A

abnormal signaling through the heart

39
Q

what is the most common mechanism of arrythmias

A

reentry

40
Q

what is reentry caused by

A

a block and/or slowed conduction

41
Q

how can reentry be defined (two ways)

A
  • anatomically defined
  • functionally defined
42
Q

what is an electrocardiogram

A

external measure of electrical activity of the heart

43
Q

what is the body

EKG

A

a conductor

44
Q

the length and amplitude of waves depend on what two factors

A
  • size of the sum of potentials
  • synchronicity of potentials
45
Q

what is an electrical dipole

A

a pair of electrical charges separated by a distance

ex: flashlight battery (+ and - end)

46
Q

what happens when a dipole is placed into a conductive medium

A

ionic currents will flow through medium and relative differences in polarity can be detected

47
Q

what does the P wave mean

A

atrial depolarization

48
Q

what does the Q wave mean

A

early ventricular depolarization

49
Q

what does the R wave mean

A

ventricular depolarization

due to left side bigger than right

50
Q

what does the S wave mean

A

late ventricular depolarization

51
Q

what does thr T wave mean

A

ventricular repolarization

52
Q

what is Einthoven’s Law

A

any two of the three bipolar limb leads determine the third one
* lead 1 + lead 3 = lead 2

Circulation and Respiration (7 decks)

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