Biol2420 - Peripheral Nervous System (Pns)

Front 1

What does the Peripheral Nervous System include?

Back 1

It includes 12 pairs of cranial nerves that arise from the brain
and
31 pairs of spinal nerves that arise from the spinal cord

Hint 1

Pg. 105

Front 2

What type of nerve classifications are the all spinal nerves?

Back 2

Mixed Nerves

Hint 2

Pg. 105

Front 3

How can the motor axons in the PNS be activated?

Back 3

They can be activated by association neurons in the CNS
and
Through reflex arcs involving sensory neurons

Hint 3

Pg. 105

Front 4

Where specifically do the 12 pairs of cranial nervous arise?

Back 4

2 pairs arise from neuron cell bodies in the forebrain.
and
10 pairs arise from the midbrain and hindbrain

Hint 4

Pg. 105

Front 5

How are the 31 pairs of spinal nerves designated?

Back 5

By where they arise in the spinal cord

Hint 5

Pg. 105

Front 6

What are the specific designations of the spinal nerves?

Back 6

1. 8 cervical
2. 12 thoracic
3. 5 lumbar
4. 5 sacral
5. 1 coccygeal

Hint 6

Pg. 105

Front 7

What is the term for region where axons from different levels of the spinal cord come together?

Back 7

Plexuses

Hint 7

Pg. 105

Front 8

Why can plexuses give rise to nerves that can be quite large?

Back 8

Because they contain axons from different spinal cord levels

Hint 8

Pg. 105

Front 9

What nerve is a great example of a plexus?

Back 9

The Sciatic Nerve

Hint 9

Pg. 105

Front 10

What kinds of functions do Spinal Nerves provide?

Back 10

Sensory functions
and
Motor functions

Hint 10

Pg. 105

Front 11

Why is each spinal nerve a mixed nerve?

Back 11

Because it is composed of sensory and motor axons

Hint 11

Pg. 106

Front 12

Where do the 2 different kinds of axons composing spinal nerves separate?

Back 12

They separate near the root of the nerve in the spinal cord

Hint 12

Pg. 106

Front 13

Where specifically do the sensory axons of the spinal cord arise?

Back 13

The enter the spinal cord on the Dorsal side (back side)

Hint 13

Pg. 106

Front 14

Where specifically do the motor axons of the spinal cord arise?

Back 14

The exit on the Ventral side (Belly side)

Hint 14

Pg. 106

Front 15

What do the sensory neurons of the spinal nerve form?

Back 15

The Dorsal Root

Hint 15

Pg. 106

Front 16

What do the motor neurons of the spinal nerve form?

Back 16

The Ventral Root

Hint 16

Pg. 106

Front 17

What kind of neurons can stimulate motor neurons?

Back 17

Sensory Neurons
or
Association Neurons

Hint 17

Pg. 106

Front 18

What does stimulation of spinal motor neurons by association neurons allow for?

Back 18

It allows for Motor Control
and
Reflex Activity

Hint 18

Pg. 106

Front 19

What is the specific name of the association neurons that stimulate spinal motor neurons allowing for motor control?

Back 19

Upper Motor Neurons

Hint 19

Pg. 106

Front 20

What do somatic motor neurons stimulate?

Back 20

Skeletal Muscles

Hint 20

Pg. 106

Front 21

What are Somatic Motor Neurons also called?

Back 21

Lower Motor Neurons

Hint 21

Pg. 106

Front 22

What do the neuron cell bodies of the sensory neurons in a spinal nerve grouped together form and what are these structures called?

Back 22

They form a bulge in the dorsal roots of each spinal nerve
and
They are called the Dorsal Root Ganglia

Hint 22

Pg. 106

Front 23

Where do somatic motor neurons hall their cell bodies?

Back 23

They have their cell bodies in the gray matter of the spinal cord.

Hint 23

Pg. 106

Front 24

What kinds of motor neurons participate in spinal reflexes?

Back 24

Somatic Motor Neurons

Hint 24

Pg. 106

Front 25

What is the term given for the simplest spinal reflex?

Back 25

Monosynaptic Muscle Stretch Reflex

Hint 25

Pg. 106

Front 26

Why is the simplest spinal reflex monosynaptic?

Back 26

Because only one synapse is crossed in the CNS.

Hint 26

Pg. 106

Front 27

What is the best-known example of a monosynaptic muscle stretch reflex?

Back 27

The Knee-Jerk Reflex

Hint 27

Pg. 106

Front 28

In the knee-jerk reflex, when the patellar ligament is struck with a rubber mallet a quick stretch is produced in the quadriceps femoris muscle. What does the quick stretch of the muscles serve as a stimulus for and what is this structure called?

Back 28

It serves as a stimulus for the muscle stretch receptor
and
It is known as the Muscle Spindle

Hint 28

Pg. 106

Front 29

What does each muscle spindle contain?

Back 29

It contains several thin muscle fibers.

Hint 29

Pg. 106

Front 30

What is the name of the thin muscle fibers found within a muscle spindle?

Back 30

Intrafusal Fibers

Hint 30

Pg. 106

Front 31

What structure is stimulated when a muscle spindle is stretched?

Back 31

Sensory Dendrites

Hint 31

Pg. 106

Front 32

What is produced when stretching of the spindle stimulates sensory dendrites around the intrafusal fibers?

Back 32

Action Potentials are produced and are conducted by the sensory neuron into the spinal cord.

Hint 32

Pg. 106

Front 33

What is inhibited when a muscle is stretched slowly?

Back 33

Contraction

Hint 33

Pg. 107

Front 34

What receptor is activated in the inhibitory contraction reflex when a muscle is stretched?

Back 34

The Golgi Tendon Organ

Hint 34

Pg. 107

Front 35

What are muscles that produce opposing movements of bones at a joint called?

Back 35

Antagonistic Muscles

Hint 35

Pg. 107

Front 36

What is Stimulation of the motor neurons to the agonist muscle and inhibition of the motor neurons to the antagonist muscle known as?

Back 36

Reciprocal Innervation

Hint 36

Pg. 107

Front 37

What is each skeletal muscle fiber stimulated by?

Back 37

Each skeletal muscle fiber is stimulated by one somatic motor neuron.

Hint 37

Pg. 107

Front 38

What is a synapse between a somatic motor neuron and a skeletal muscle fiber called?

Back 38

A Neuromuscular Junction

Hint 38

Pg. 107

Front 39

What kind of ACh receptors do skeletal muscles have?

Back 39

Nicotinic ACh receptors

Hint 39

Pg. 107

Front 40

What is formed from muscle fibers and the somatic motor neurons that innervate the fibers?

Back 40

A Motor Unit

Hint 40

Pg. 108

Front 41

What must be achieved if a stronger muscle contraction is desired and what is this called?

Back 41

More and larger motor units must be activated
and
This process is called Recruitment

Hint 41

Pg. 108

Front 42

What do smaller motor units achieve?

Back 42

They achieve a finer degree of neural control over the muscle’s contraction

Hint 42

Pg. 108

Front 43

What is the Autonomic Nervous System composed of?

Back 43

Parasympathetic and Sympathetic motor Neurons
and
The brain regions that regulate their activities

Hint 43

Pg. 108

Front 44

What function do the Preganglionic Autonomic Neurons serve?

Back 44

They send axons out of the CNS to ganglia

Hint 44

Pg. 108

Front 45

What function do the Postganglionic Autonomic Neurons serve?

Back 45

They send axons from the ganglia to the effector cells they innervate

Hint 45

Pg. 108

Front 46

What do Somatic Motor Neurons Innervate?

Back 46

Voluntary Skeletal Muscle

Hint 46

Pg. 108

Front 47

What do Autonomic Motor Neurons Innervate?

Back 47

Cardiac Muscle, Smooth Muscle and Glands

Hint 47

Pg. 108

Front 48

How many neurons are in the efferent pathway extending to skeletal muscle fibers in its motor unit?

Back 48

1 Neuron

Hint 48

Pg. 109

Front 49

How many autonomic neurons are in the efferent pathway to the involuntary effector cells?

Back 49

2 Autonomic Neurons

Hint 49

Pg. 109

Front 50

What are the autonomic neurons called that regulate involuntary effector cells?

Back 50

Postganglionic Neurons

Hint 50

Pg. 109

Front 51

What stimulates postganglionic neurons?

Back 51

Preganglionic Neurons

Hint 51

Pg. 109

Front 52

Where do preganglionic neurons have their cell body?

Back 52

In the CNS

Hint 52

Pg. 109

Front 53

What ganglionic neuron type synapses with the effector cells?

Back 53

Postganglionic Neurons

Hint 53

Pg. 109

Front 54

What division of the autonomic nervous system has chains of ganglia?

Back 54

The Sympathetic Division

Hint 54

Pg. 109

Front 55

What can the sympathetic division of the autonomic nervous system also be called?

Back 55

The Thoracolumbar Division

Hint 55

Pg. 109

Front 56

Why is the Sympathetic division of the autonomic nervous system also called the Thoracolumbar division?

Back 56

Because it’s preganglionic neurons have cell bodies in each level of the spinal cord from the first thoracic to the second lumbar levels.

Hint 56

Pg. 109

Front 57

Where do the preganglionic axons exit?

Back 57

At each spinal level they exit in the ventral roots of the spinal nerve.

Hint 57

Pg. 109

Front 58

Where do the preganglionic axons synapse with the postganglionic neurons?

Back 58

In the Sympathetic Ganglion

Hint 58

Pg. 109

Front 59

What happens when the preganglionic axons enter the sympathetic ganglia?

Back 59

The axons branch to form collaterals that travel up and down the sympathetic chain of ganglia, synapsing with postganglionic neurons at different levels.

Hint 59

Pg. 110

Front 60

What is one body location where some preganglionic axons enter the chain of ganglia but don’t synapse there?

Back 60

In the Abdomen

Hint 60

Pg. 110

Front 61

Where do some abdominal preganglionic axons synapse?

Back 61

They synapse with 3 Collateral Sympathetic Ganglia associated with the digestive tract.

Hint 61

Pg. 110

Front 62

Where are the adrenal glands located?

Back 62

Above each Kidney

Hint 62

Pg. 110

Front 63

What is the outer part of the adrenal gland called?

Back 63

The Adrenal Cortex

Hint 63

Pg. 110

Front 64

What is the inner part of the adrenal gland called?

Back 64

The Adrenal Medulla

Hint 64

Pg. 110

Front 65

What is the adrenal medulla derived from?

Back 65

The embryonic neural crest
or
The same tissue that gives rise to the ganglia of the PNS

Hint 65

Pg. 110

Front 66

What type of axons stimulate the inner part of the adrenal gland to secrete adrenaline?

Back 66

Preganglionic sympathetic axons

Hint 66

Pg. 110

Front 67

What does the secretion of epinephrine from the inner part of the adrenal gland accompany?

Back 67

It accompanies the activation of the sympathetic division of the ANS.

Hint 67

Pg. 110

Front 68

What name is given for the sympathetic division of the ANS and adrenal medulla function?

Back 68

Sympathoadrenal System

Hint 68

Pg. 110

Front 69

What Autonomic Nervous System division has terminal ganglia?

Back 69

The Parasympathetic Division
or
The Craniosacral Division

Hint 69

Pg. 110

Front 70

Why is the Parasympathetic division of the ANS also called the Craniosacral division?

Back 70

Because it’s preganglionic neurons have their cell bodies in the brain and sacral region of the spinal cord.

Hint 70

Pg. 110

Front 71

True or Flase. Parasympathetic Ganglia are arranged in a chain just like the sympathetic ganglia.

Back 71

Flase. They are not in a chain.

Hint 71

Pg. 110

Front 72

Where are the terminal ganglia located?

Back 72

Next to the organs they serve
or
Within the organs they serve

Hint 72

Pg. 110

Front 73

Where do preganglionic parasympathetic axons that travel within several cranial nerves synapse?

Back 73

They synapse in terminal ganglia near the eyeballs, salivary glands and lacrimal glands.

Hint 73

Pg. 111

Front 74

Where do the preganglionic parasympathetic axons in the oculomotor nerve synapse?

Back 74

The Ciliary Region

Hint 74

Pg. 111

Front 75

What happens when the iris of the eye receives parasympathetic stimulation?

Back 75

It Constricts, making the pupil smaller.

Hint 75

Pg. 111

Front 76

What happens when the iris of the eye receives sympathetic stimulation?

Back 76

It Dilates, making the pupil larger.

Hint 76

Pg. 111

Front 77

Where do the preganglionic neurons of cranial nerve X have their cell bodies?

Back 77

In the Medulla Oblongata

Hint 77

Pg. 111

Front 78

What does the preganglionic neurons of the Autonomic Nervous System release and what does it stimulate?

Back 78

ACh
and
It stimulates the postganglionic neurons

Hint 78

Pg. 111

Front 79

What do postganglionic sympathetic axons release?

Back 79

Norepinephrine

Hint 79

Pg. 111

Front 80

What type of effect is produced when postganglionic sympathetic axons release Norepinephrine?

Back 80

An Adrenergic effect

Hint 80

Pg. 111

Front 81

What do postganglionic parasympathetic axons release?

Back 81

ACh

Hint 81

Pg. 111

Front 82

What type of effect is produced when postganglionic parasympathetic axons release ACh?

Back 82

A Cholinergic effect

Hint 82

Pg. 111

Front 83

Describe what happens to your heart, blood vessels in your skin and muscles, and your blood glucose concentration, when you are scared or anxious?

Back 83

1) Increased pumping by your heart
2) Increased blood flow to your muscles
3) Increased levels of blood glucose
4) Decreased blood flow to your skin
5) Decreased digestive activity

Hint 83

Pg. 112

Front 84

How are the effects of a motor neuron produced?

Back 84

The effects of a motor neuron are produced by the neurotransmitter it releases.

Hint 84

Pg. 112

Front 85

Why is the naming of neurotransmitters a little more involved in the ANS?

Back 85

Be cause there are both preganglionic and postganglionic neurons in the ANS, and both sympathetic and parasympathetic divisions.

Hint 85

Pg. 112

Front 86

What do all preganglionic neurons release?

Back 86

ACh

Hint 86

Pg. 112

Front 87

What do most postganglionic axons of the parasympathetic division release?

Back 87

ACh

Hint 87

Pg. 112

Front 88

What term describes the synaptic transmission that uses ACh as a neurotransmitter?

Back 88

Cholinergic

Hint 88

Pg. 112

Front 89

What do most postganglionic sympathetic axons releases?

Back 89

Norepinephrine

Hint 89

Pg. 112

Front 90

What kind of receptors does the protein released by most postganglionic sympathetic axons bind to?

Back 90

Adrenergic Receptors

Hint 90

Pg. 112

Front 91

What term describes the synaptic transmission that uses Norepinephrine as a neurotransmitter?

Back 91

Adrenergic

Hint 91

Pg. 112

Front 92

What is the regulation produced by postsynaptic neurons of the ANS due to?

Back 92

It is due to their cholinergic or adrenergic effects on cardiac muscle, smooth muscle, and glands.

Hint 92

Pg. 113

Front 93

What kind of receptors does the sympathoadrenal system activate?

Back 93

It activates different adrenergic receptors

Hint 93

Pg. 113

Front 94

What are the 2 types of ACh receptors?

Back 94

Nicotinic
and
Muscarinic

Hint 94

Pg. 113

Front 95

What are the 2 major types of receptors that both norepinephrine and epinephrine bind to?

Back 95

Alpha Adrenergic Receptors
and
Beta Adrenergic receptors

Hint 95

Pg. 113

Front 96

True or False. The binding of norepinephrine and epinephrine activates both types of adrenergic receptors. This process also produces the same effects in different organs.

Back 96

False. Although true, the binding of norepinephrine and epinephrine activates both types of adrenergic receptors. This binding produces different effects in different organs.

Hint 96

Pg. 113

Front 97

What are the subtypes of receptors that both norepinephrine and epinephrine bind to?

Back 97

1) Alpha 1
2) Alpha 2
3) Beta 1
4) Beta 2

Hint 97

Pg. 113

Front 98

What type of body structure contains effector cells that have more of one subtype of adrenergic receptors compared to the others?

Back 98

Organs

Hint 98

Pg. 113

Front 99

What type of adrenergic receptors do cardiac muscle cells have?

Back 99

Beta 1

Hint 99

Pg. 113

Front 100

What type of adrenergic receptors do the smooth muscle cells of the lungs have?

Back 100

Beta 2

Hint 100

Pg. 113

Front 101

What type of adrenergic receptors are characteristic of vascular smooth muscle?

Back 101

Alpha 1

Hint 101

Pg. 113

Front 102

What type of effect do alpha 1 adrenergic receptors stimulate in vascular smooth muscle?

Back 102

They stimulate their contraction
or
Cause Vasoconstriction

Hint 102

Pg. 113

Front 103

What does the Sympathoadrenal stimulation of adrenergic receptors prepare the body for?

Back 103

It prepares the body for “Fight-or-Flight”

Hint 103

Pg. 113

Front 104

What type of effect does the stimulation of Beta 2 receptors have on the airways?

Back 104

Dilation of the bronchioles of the lungs

Hint 104

Pg. 113

Front 105

What type of effect does the stimulation of Beta 1 receptors have on the heart?

Back 105

Increase in beating rate
and
Increase in contraction strength

Hint 105

Pg. 113

Front 106

What is the breakdown of the largest organ in the body’s glycogen called?

Back 106

Glycogenolysis

Hint 106

Pg. 113

Front 107

What type of effect does the stimulation of alpha 1 receptors have in the largest organ of the body and visceral organs?

Back 107

It causes Vasoconstriction

Hint 107

Pg. 113

Front 108

What type of specific adrenergic receptor is stimulated in the inhibition of the digestive system?

Back 108

Alpha 1 receptors

Hint 108

Pg. 114

Front 109

What specific receptor is stimulated and what stimulates the receptor in the vasodilation in skeletal muscles?

Back 109

Beta 2 receptors
and
The hormone epinephrine stimulates the receptors

Hint 109

Pg. 114

Front 110

What type of adrenergic receptor is different from the other subtypes and why?

Back 110

The Alpha 2 receptors are different
Because they are mostly found in presynaptic axon terminals

Hint 110

Pg. 114

Front 111

What effect does stimulation of Alpha 2 receptors in the CNS have?

Back 111

Activity of the Sympathoadrenal System is reduced

Hint 111

Pg. 114

Front 112

What type of adrenergic receptor should be inhibited by a drug in someone with hypertension?

Back 112

Beta 1 receptors

Hint 112

Pg. 114

Front 113

What type of adrenergic receptor should be stimulated by a drug in someone with asthma?

Back 113

Beta 2 receptors

Hint 113

Pg. 114

Front 114

What specific receptor is activated with drugs that stimulates the heart?

Back 114

Beta 1 receptors

Hint 114

Pg. 114

Front 115

What type of adrenergic receptor is stimulated with drugs that promote vasoconstriction?

Back 115

Alpha 1 receptors

Hint 115

Pg. 114

Front 116

What type of adrenergic receptor is stimulated by drugs that depress the sympathoadrenal system in the CNS?

Back 116

Alpha 2 receptors

Hint 116

Pg. 114

Front 117

True or Flase. Parasympathetic regulation is mostly adrenergic?

Back 117

False. Parasympathetic regulation is mostly cholinergic

Hint 117

Pg. 114

Front 118

What are synapses that use Acetylcholine as a neurotransmitter described as?

Back 118

They are described as Cholinergic Synapses

Hint 118

Pg. 114

Front 119

What receptors might ACh bind to and where are they found?

Back 119

Nicotinic or Muscarinic
They are found in the postsynaptic membrane

Hint 119

Pg. 114

Front 120

What type of ACh receptors are in skeletal muscles and in dendrites of postganglionic neurons of the Autonomic Nervous System?

Back 120

Nicotinic receptors

Hint 120

Pg. 114

Front 121

What type of ACh receptors are in cardiac muscle, smooth muscle and glands?

Back 121

Muscarinic receptors

Hint 121

pg. 114

Front 122

What specifically releases the ACh received by the ACh receptors in the cardiac muscle, smooth muscle and glands?

Back 122

Postganglionic Axons of the Parasympathetic division

Hint 122

pg. 114

Front 123

What are parasympathetic nerve effects on the organs of the viscera classified as?

Back 123

Muscarinic Cholinergic effects

Hint 123

pg. 114

Front 124

Nicotinic ACh receptors are also ______________that produce ________________thus, they are ____________________

Back 124

Ion channels
Depolarizations or (EPSPs)
Always stimulatory

Hint 124

pg. 114

Front 125

True or False. Nicotinic ACh receptors are both inhibitory and stimulatory?

Back 125

Flase. Nicotinic ACh receptors are always stimulatory

Hint 125

pg. 114

Front 126

What are Muscarinic ACh receptors separate from?

Back 126

The Ion Channels

Hint 126

pg. 114

Front 127

How do Muscarinic ACh receptors communicate with the ion channels?

Back 127

They communicate with the ion channels by means of G-Proteins

Hint 127

Pg. 114

Front 128

What type of ACh receptors are both stimulatory and inhibitory and why?

Back 128

Muscarinic receptors
Because the ion channels are separate from the muscarinic receptors. Once ACh binds to a muscarinic ACh receptor, it can cause either depolarization and stimulation, or hyperpolarization and inhibition.

Hint 128

Pg. 114

Front 129

What effect is the promotion of contrations and secretions of the digestive system an example of?

Back 129

It is an example of parasympathetic stimulation

Hint 129

Pg. 114

Front 130

What type of substance can inhibit the effect that slows the heart rate?

Back 130

Atropine

Hint 130

Pg. 115

Front 131

What does Atropine and its analogs accomplish?

Back 131

They are drugs that specifically block the Muscarinic ACh receptors

Hint 131

Pg. 115

Front 132

What are some examples of the effects of stimulation of Muscarinic ACh receptors?

Back 132

1) Constriction of the pupils of the eyes
2) Constriction of the pulmonary airways
3) Secretion of Salivary glands and mucus glands
4) Slowing the heart rate
5) Contractions of the G.I tract and secretions of the organs of the digestive system
6) Vasodilation in the genital organs, digestive system and other visceral organs

Hint 132

Pg. 115