Brainscape's Knowledge GenomeTM

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


See full index

Physiology FoM > Autonomic nervous system > Flashcards

Autonomic nervous system Flashcards

1
Q

Describe the nervous system

A
  • Central nervous system- brain and spinal cord
  • Peripheral nervous system
  • > Somatic (voluntary)- sensory nerves and motor nerves
  • > Autonomic (involuntary)- enteric, smooth muscle, glands, systems, self-governing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe ANS in homeostasis

A
  • Areas of control in CNS receive input signals
  • > Control centres (hypothalamus, spinal cord or brainstem) set points for various parameters
  • > Directly or by sensory afferents
  • ANS- effector arm of homeostatic regulation- provides efferent pathway
  • Pre- and post-ganglionic neurons
  • > Adrenal medulla innervated by long pre-ganglionic nerve
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the two components of the autonomic nervous system?

A
  • Sympathetic

- Parasympathetic

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

Describe the sympathetic nervous system

A
  • Spinal cord segments T1 to L2
  • > Short pre-ganglionic fibres and long post-ganglionic fibres- catecholamines (e.g. adrenaline)
  • -> Except sweat glands- cholinergic sympathetics
  • > functions include fight or flight
  • Increased heart rate, airway dilation, pupil dilation, increased glucose, decreased gut motility
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe the parasympathetic nervous system

A
  • Cranial-sacral (C3,7,9&10) (S2,3&4)
  • > Long pre-ganglionic fibres and short post-ganglionic fibres- uses acetlycholine
  • Functions include rest and digest
  • Targets specific and often overriden by SNS
  • -> GI tract- increased motility, pupils and lens adjusted for close vision, normal heart rate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the agonistic effects of the SNS and PNS?

A
  • Heart rate

- Gut motility

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

What are the interactions of the SNS and PNS?

A
  • Antagonistic
  • Complementary- to a similar end
  • Co-operative- play roles in some stage of overall function
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the complementary effects of the SNS and PNS?

A
  • Salivary secretion primarily controlled by PNS in response to presence of food in mouth or food senses
  • SNS does input- changes saliva composition- makes it thicker and more proteinaceous
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the cooperative effects of SNS and PNS?

A
  • Eye: SNS dilates, PNS focuses lens

- Reproduction: PNS- erection through blood vessel dilation, SNS- ejaculation- smooth muscle contraction

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

Describe neural tone

A
  • Basal activity at rest- SNS tightly constricts vessels, PNS keeps rate below 100bpm
  • Activity can increase or decrease from rest- adrenal medulla secretes adrenaline (80%) and noradrenaline (20%) into circulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Give examples of tissues that don’t have both types of innervation

A
  • Hair follicle- piloerection- SNS only
  • Blood vessels primarily SNS
  • Excludes some facial vessels and penis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe CNS control of ANS

A
  • ANS acts as an effector after information retrieval from CNS
  • Key areas: spinal cord, brainstem (medulla) receives sensory, hypothalamus and cerebral cortex
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the role of the hypothalamus in ANS control

A
  • Main integration centre for autonomic- location for set point in negative feedback
  • -> Body temp, osmolality, hunger etc.
  • Regulates homeostatic activity of ANS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the role of the cerebral cortex in ANS control

A
  • Higher brain area
  • no conscious control over ANS normally
  • Many bodily functions require interaction between SNS and PNS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the micturition reflex?

A
  • Urination usually voluntary- ANS helps prevent incontinence
  • PNS: fibres detect bladder stretch, smooth muscle contraction
  • SNS: smaller role, diminishes smooth muscle contraction, constricts internal sphincter
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the action of bladder emptying

A
  • PNS monitors filling, signals relay to cerebral cortex via spinal cord
  • Spinal cord sends signals back down somatic fibres to external sphincter (opens or not)
  • Flow receptors (ANS) monitor flow
17
Q

Describe the interactions of ANS and SNS in the micturition reflex

A
  • Bladder emptying normally voluntary
  • Continence controlled by ANS
  • Conscious somatic control of external urinary sphincter for bladder emptying
  • Urination further aided by abdominal muscle contraction and relaxation of urogenital diaphragm

Physiology FoM (6 decks)

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