Autonomic nervous system (Chapter 14)

Question 1

the involuntary arm of the peripheral nervous system, also known as the visceral motor division

Answer 1

autonomic nervous system

Question 2

the autonomic nervous system is divided into what two divisions?

Answer 2

• sympathetic

* parasympathetic

Question 3

sympathetic and parasympathetic nervous systems; constantly work together to maintain?

Answer 3

homeostasis

Question 4

The ANS oversees most vital functions including

Answer 4

• heart rate
• blood pressure
• digestive and urinary processes

Question 5

What does the autonomic motor division innervate?

Answer 5

smooth muscle cells, cardiac muscle cells, and glands; produce involuntary actions

Question 6

ANS motor neurons do not directly innervate their target cells, they need a two neuron circuit which includes?

Answer 6

• preganglionic neuron

* postganglionic neuron

Question 7

initial efferent neuron; cell body resides within CNS; all axons release acetylcholine

Answer 7

preganglionic neuron

Question 8

cell body resides in autonomic ganglion in PNS; axons travel to target cells; trigger specific changes (inhibitory or excitatory responses) by releasing either acetylcholine or norepinephrine

Answer 8

postganglionic neuron

Question 9

preganglionic axons are usually short and postganglionic axons are usually long in which division?

Answer 9

sympathetic nervous system

Question 10

preganglionic parasympathetic axons are long while postganglionic axons are short

Answer 10

parasympathetic nervous system

Question 11

Preganglionic cell bodies originate in thoracic and upper lumbar spinal cord giving rise to name

Answer 11

thoracolumbar division

Question 12

generally located near spinal cord, where preganglionic axons synapse with postganglionic neuron cell bodies; postganglionic axons proceed to target

Answer 12

sympathetic ganglia

Question 13

the “fight or flight” division of the ANS, prepares the body for emergency situations

Answer 13

sympathetic nervous system

Question 14

• Vital role in maintenance of homeostasis when body is engaged in physical work
• Mediates body’s responses to emotion

Answer 14

sympathetic nervous system

Question 15

Preganglionic cell bodies are located within nuclei of several cranial nerves in brainstem and sacral region of spinal cord giving rise to name

Answer 15

craniosacral division (parasympathetic)

Question 16

innervate structures of head and neck, thoracic viscera, and most abdominal viscera

Answer 16

cranial nerves of the parasympathetic nervous system

Question 17

innervate structures within pelvic cavity

Answer 17

sacral nerves of the parasympathetic nervous system

Question 18

Cell bodies of postganglionic neurons are usually located near target organ; requires only a short axon to make connection

Answer 18

parasympathetic nervous system

Question 19

“Rest and digest” division; role in digestion and in maintaining body’s homeostasis at rest

Answer 19

parasympathetic nervous system

Question 20

where most of postganglionic cell bodies are found; run down both sides parallel with vertebral column (Figure 14.4); “chainlike” appearance

Answer 20

sympathetic chain ganglia

Question 21

Section of chain that extends above thoracic spinal cord terminates in

Answer 21

superior cervical ganglion

Question 22

Section of chain that extends below lumbar spinal cord terminates in

Answer 22

inferior sacral ganglion

Question 23

originate in lateral horns of thoracic and lumbar spinal cord; exit with axons of lower motor neurons via anterior root

Answer 23

preganglionic neurons

Question 24

Preganglionic axons quickly separate from spinal nerve anterior ramus to form a small nerve called

Answer 24

the white (myelinated) rami communicantes

Question 25

Some preganglionic axons pass through chain ganglia without forming synapses; may form synapses with

Answer 25

collateral ganglia located near target organ

Question 26

Preganglionic axons that synapse with collateral ganglia near organs of abdominopelvic cavity are components of

Answer 26

splanchic nerves

Question 27

how do postganglionic axons exit the ganglia?

Answer 27

as small gray (unmyelinated) rami communicantes; reunite to travel with spinal nerves until they reach their target cells

Question 28

bind to specific protein-based receptors embedded in plasma membranes of target cells

Answer 28

neurotransmitters

Question 29

neurotransmitter used in excitatory synapses between sympathetic preganglionic axons and postganglionic neurons; postganglionic axons then transmit action potentials to target cell

Answer 29

Acetylcholine (ACh)

Question 30

At synapse with their target cells, postganglionic axons release one of three neurotransmitters:

Answer 30

* ACh, * epinephrine (adrenalin), * or norepinephrine (noradrenalin)

Question 31

most frequently utilized neurotransmitter released into synapses between postganglionic axons and target cells

Answer 31

norepinephrine

Question 32

Adrenergic receptors bind to?

Answer 32

norepinephrine and epinephrine

Question 33

The two major types of adrenergic receptors include?

Answer 33

alpha and beta receptors

Question 34

An adrenergic receptor in plasma membranes of smooth muscle cells of many different organs, including blood vessels in skin, GI tract, and kidneys, arrector pili muscles in dermis, and certain organs of genitourinary tract

Answer 34

alpha-1 receptors

Question 35

An adrenergic receptor in plasma membranes of preganglionic sympathetic neurons instead of in peripheral target cells

Answer 35

alpha-2 receptors

Question 36

An adrenergic receptor in plasma membranes of cardiac muscle cells, certain kidney cells, and adipose cells

Answer 36

beta-1 receptors

Question 37

An adrenergic receptor in plasma membranes of smooth muscle cells lining airways of respiratory tract (bronchioles), and in wall of urinary bladder, skeletal muscle fibers, and cells found in liver, pancreas, and salivary glands

Answer 37

beta-2 receptors

Question 38

An adrenergic receptor primarily in adipose cells and smooth muscle cells in walls of digestive tract

Answer 38

beta-3 receptors

Question 39

this class of sympathetic receptors binds to acetylcholine

Answer 39

cholinergic receptors

Question 40

What are the two types of cholinergic receptors?

Answer 40

* muscarinic | * nicotinic

Question 41

found in sweat glands of the skin

Answer 41

muscarinic receptors

Question 42

found in membranes of all postganglionic neurons within sympathetic ganglia and adrenal medullae

Answer 42

nicotinic receptors

Question 43

how does alpha-2 receptors differ from the other adrenergic receptor subtypes?

Answer 43

When norepinephrine binds to alpha-2 receptors, axon terminal is hyperpolarized; slows or cancels action potential

Question 44

occurs when norepinephrine binds to alpha-1 receptors; decreases blood flow to these organs

Answer 44

constriction of blood vessels serving the digestive, urinary, and integumentary system

Question 45

occurs when norepinephrine binds to beta-2 receptors; increases amount of air that can be inhaled with each breath

Answer 45

dilation of bronchioles

Question 46

occurs when norepinephrine binds to beta-2 receptors; increases blood flow; allows for an increase in physical activity

Answer 46

dilation of blood vessels serving the skeletal and cardiac muscles

Question 47

occurs when norepinephrine binds to beta-2 and beta-3 receptors respectively; makes emptying bladder and bowel more difficult during increased physical activity

Answer 47

contraction of urinary and digestive sphincters

Question 48

occurs when norepinephrine binds to beta-2 receptors; slows digestion during increased physical activity

Answer 48

relaxation of the smooth muscle of the digestive tract

Question 49

occurs when norepinephrine binds to alpha-1 receptors; causes dilator pupillae muscles to contract; causes pupil to allow more light into eye

Answer 49

dilation of the pupils

Question 50

occurs when norepinephrine binds to beta receptors on blood vessels serving various glands (like salivary glands); decreases secretion, except in sweat glands

Answer 50

Constriction of blood vessels serving most exocrine glands

Question 51

occurs during times of sympathetic activation, nearly all cells, especially skeletal muscle, require higher amounts of ATP

Answer 51

effects on cellular metabolism

Question 52

To assist with the higher energy demand norepinephrine has the following three effects:

Answer 52

1. Beta-3 receptors on adipocytes; triggers breakdown of lipids; releases free fatty acids into bloodstream 2. Beta-2 receptors on liver cells; triggers release of glucose from glycogen and synthesis of glucose from other resources 3. Binds to beta-2 receptors on cells of pancreas; triggers release of hormone glucagon; increases blood glucose levels

Question 53

ACh is released from preganglionic neurons; binds to?

Answer 53

nicotinic receptors on adrenal medulla cells

Question 54

ACh stimulates medullary cells to release

Answer 54

norepinephrine and epinephrine into bloodstream

Question 55

“Rest and digest” division of ANS | Role in body’s maintenance functions, such as digestion and urine formation

Answer 55

parasympathetic nervous system

Question 56

Known as craniosacral division based on association with cranial nerves and pelvic nerves from sacral plexus

Answer 56

parasympathetic nervous system

Question 57

associated with oculomotor (CN III), facial (CN VII), glossopharyngeal (CN IX), and vagus (CN X) nerves

Answer 57

parasympathetic cranial nerves

Question 58

the main parasympathetic nerves that innervate most thoracic and abdominal viscera

Answer 58

two vagus nerves

Question 59

Branches of the vagus nerves contribute to?

Answer 59

* cardiac * pulmonary * esophageal

Question 60

Preganglionic axons in oculomotor (CN III) nerve synapse with

Answer 60

ciliary ganglia

Question 61

house cell bodies of sensory neurons and synapse with facial (CN VII) nerve

Answer 61

Submandibular and pterygopalatine ganglia

Question 62

make up pelvic nerve component of this division; innervates last segment of large intestine, urinary bladder, and reproductive organs

Answer 62

Parasympathetic sacral nerves

Question 63

Sacral nerve branches form?

Answer 63

the pelvic splanchnic nerves, forms plexuses in the pelvic floor

Question 64

located in membranes of all postganglionic neurons

Answer 64

nicotinic receptors

Question 65

located in membranes of all parasympathetic target cells

Answer 65

muscarinic receptors

Question 66

Parasympathetic activity decreases heart rate and blood pressure Preganglionic parasympathetic neurons travel to heart with vagus nerve (CN X)

Answer 66

effects on cardiac muscle in the parasympathetic nervous system

Question 67

effects on smooth muscle cells in the PNS include:

Answer 67

* constriction of the pupil * accommodation of the lens for near vision * constriction of the bronchioles * contraction of the smooth muscle lining the digestive tract * relaxation of the digestive and urinary sphincters * engorgement of the penis or clitoris

Question 68

involves CN III, ciliary ganglion, and sphincter pupillae muscle; reduces amount of light allowed into eye

Answer 68

constriction of the pupil

Question 69

involves CN III and contraction of ciliary muscle; changes lens to a more rounded shaped

Answer 69

accommodation of the lens for near vision

Question 70

involves CN X; reduces air flow through bronchioles

Answer 70

Constriction of bronchioles (bronchoconstriction)

Question 71

involves CN X; produces rhythmic contractions called peristalsis; propels food through digestive tract

Answer 71

Contraction of smooth muscle lining digestive tract

Question 72

involves CN X and sacral nerves; promotes urination and defecation

Answer 72

Relaxation of digestive and urinary sphincters

Question 73

occurs when stimulated by sacral nerves in male or female respectively

Answer 73

engorgement of the penis and the clitoris

Question 74

* CN VII stimulation stimulates tear production from lacrimal glands and mucus production from glands in nasal mucosa * CN VII and IX stimulation leads to increased production of saliva from salivary glands * CN X stimulates secretion of enzymes and other products from digestive tract cells

Answer 74

Effects on glandular epithethelial cells

Question 75

What are some side effects of anticholinergic drugs that block the parasympathetic nervous system?

Answer 75

* urinary retention * constipation * dry mouth

Question 76

What are some side effects of anticholinergic drugs that activate the parasympathetic nervous system?

Answer 76

constricted airways

Question 77

innervate many of same organs where their actions antagonize one another, a condition called dual innervation

Answer 77

both sympathetic and parasympathetic divisions

Question 78

refers to fact that neither division is ever completely shut down; constant amount of activity from each division

Answer 78

autonomic tone

Question 79

dominates in blood vessels; keeps them partially constricted

Answer 79

sympathetic tone

Question 80

dominates in heart; keeps heart rate at an average of 72 beats per minute

Answer 80

parasympathetic tone

Question 81

how is homeostasis controlled?

Answer 81

centrally by hypothalamus and brainstem reticular formation; actions carried out by the two divisions of ANS

Question 82

regions found in reticular formation that contact hypothalamus; contain neurons that control activity of preganglionic sympathetic and parasympathetic neurons

Answer 82

autonomic centers

Question 83

what nerve is associated with crutch paralysis?

Answer 83

radial nerve

Question 84

what do nicotinic receptors do to the heart rate for each division?

Answer 84

* increases heart in sympathetic division | * decreases heart rate in parasympathetic division

Question 85

what occurs when poison inactivates AChE?

Answer 85

there will be a lot more ACh, enzyme that breaks it down will be missing

Question 86

what happens when agonist activate beta adrenergic receptors?

Answer 86

sympathetic nervous system dilates airways