Wk 5: ANS

Question 1

ANS

Answer 1

component of the peripheral nervous system

Regulates involuntary physiologic processes

Question 2

Hypothalamus

Answer 2

controls ANS and is responsible for basic survival strategies

Question 3

Sympathetic origin of fibres

Answer 3

thoracolumbar region of spinal cord

Question 4

Sympathetic length of fibres

Answer 4

Short preganglionic

Question 5

Sympathetic location of ganglia

Answer 5

Close to spinal cord

Question 6

Asympathetic origin of fibres

Answer 6

brain and sacral spinal cord

Question 7

Asympathetic length of fibres

Answer 7

Long preganglionic

Question 8

Asympathetic location of ganglia

Answer 8

In visceral effector organs

Question 9

Sympathetic division functions

Answer 9

“Fight or Flight”

Promotes adjustments during exercise, or when threatened

• Increased heart rate
• Blood flow is shunted to muscles and heart
• Bronchioles dilate
• Liver releases glucose (from glycogen)

Question 10

Parasympathetic division functions

Answer 10

Promotes maintenance activities and conserves body energy
After eating:

• ↓ blood pressure, heart rate deceleration, ↓ respiration rate
• Gastrointestinal tract activity is high

Question 11

Sympathetic tone

Answer 11

keeps the blood vessels in a continual state of partial constriction

Question 12

Special cases for SNS

Answer 12

• Innervation of adrenal gland (one ganglionic neuron)
• Innervation of sweat glands (release of Ach by post ganglionic neuron acting on muscarinic receptors in sweat glands)

Question 13

Reflex

Answer 13

involuntary, fast and automatic response to a specific sensory stimulus

Question 14

Areflexia

Answer 14

absence of reflexes

Question 15

Hyperreflexia

Answer 15

Increased or overactive reflexes

Question 16

Hyporeflexia

Answer 16

Decreased reflexes

Question 17

Reflexes can be

Answer 17

Innate
Visceral
Spinal
Mono

Question 18

Innate reflexes

Answer 18

neural reflexes, formed before birth and can disappeared with age

Question 19

Grasp reflex (innate)

Answer 19

grabbing object if object touch palm

Question 20

Moro reflex (innate)

Answer 20

protective motor response against abrupt disruption of body balance

Question 21

Visceral reflexes

Answer 21

• Autonomic (e.g. control of heart rate)
• Or somatic reflexes (e.g. stretch such as patellar reflex)

Question 22

Spinal reflexes

Answer 22

the spinal cord is the integration centre

• Cranial reflexes where the brain is only the integration centre (e.g. pupillary reflex)

Question 23

Mono reflexes

Answer 23

one synapse involved (e.g. patellar reflex)

• Or poly-synaptic: such as the crossed extensor reflex or withdrawal reflex.

Question 24

Components of a reflex arc

Answer 24

Sensory receptor
Motor neuron
Effector
Integrating centre
Sensory neuron

Question 25

Sensory receptor

Answer 25

activated in response to stimulus

Question 26

Motor neuron

Answer 26

neuron conducting impulses from integrating centre to effector

Question 27

Effector

Answer 27

muscle or gland that responds to motor nerve impulses

Question 28

Integrating centre

Answer 28

1+ regions within the CNS that relay impulse from sensory to motor neurons

Question 29

Sensory neuron

Answer 29

conduct impulses from receptor to integrating centre

Question 30

Somatic spinal reflexes are important reflexes since they can

Answer 30

* Contribute to posture and muscle tone * Lead to adjustment of muscle tone dependent on task * Compensate large disturbances

Question 31

Types of spinal reflexes

Answer 31

Stretch Tendon Flexor or withdrawal reflex Crossed extensor reflex

Question 32

Flexor or withdrawal reflex (spinal reflex)

Answer 32

when pain receptors (nociceptors) are activated it causes automatic withdrawal of the threatened body part

Question 33

Crossed extensor reflex (spinal reflex)

Answer 33

complex reflex consisting of an ipsilateral withdrawal reflex and a contralateral extensor reflex

Question 34

Stretch (spinal reflex)

Answer 34

usually monitor muscle length * Sensory receptors (muscled spindles) activate when a muscle is stretched

Question 35

Tendon (spinal reflex)

Answer 35

monitors external tension produced during muscular contraction to prevent tendon damage. * Controls muscle tension by causing muscle relaxation * Receptor (golgi tendon organ) is in the tendon of the muscle * Activated by stretching of tendon

Question 36

Ageing effects on nervous system

Answer 36

* Rapid decline in brain weight * Reduced bulk of gyri and widening of sulci * Reduction of synaptic connections and neurons * Reduced biochemical activity

Question 37

The signs of NS ageing can be

Answer 37

* Altered sleep patterns * Changes in mood, irritability * Loss of appetite, constipation * Loss of memory