Chapter 15 Flashcards
1
Q
Somatic nervous system
A
Consist of somatic motor neurons innervate skeletal muscles of the body affect is always excitation
Voluntary control
2
Q
Autonomic nervous system (ANS)
A
Regulates cardiac muscle smooth muscles and glands referred to as visceral effectors
3
Q
Visceral effectors
A
Associated with the viscera (internal organs) of the body
4
Q
Bio feedback
A
Monitoring devices display information about a body functions such as heart rate or blood pressure
5
Q
Interoceptors
A
Sensory receptors located in blood vessels, visceral organs, muscles, and the nervous system that monitor conditions in the internal environment
6
Q
Two main branches of the ANS system
A
Sympathetic nervous system and parasympathetic nervous system
7
Q
What’s the term that describes organs that receive nerves from both divisions of the ANS
A
Dual innervation
8
Q
Fight or flight response is part of which system?
A
Sympathetic nervous system
9
Q
Rest and digest activities are part of which nervous system?
A
Parasympathetic nervous system
10
Q
Enteric nervous system
A
Consists of millions of neurons in plexuses that extend most of the length of the G.I. tract, involuntary
11
Q
Ganglion
A
Collection of neuron cell bodies in the peripheral nervous system
12
Q
Chromaffin cells
A
Located in the adrenal medulle secrete neurotransmitters epi-nephron and norepinephrine
13
Q
What are the two motor neurons in any autonomic motor pathway called?
A
Postganglionic neuron and autonomic ganglion
14
Q
Where are the preganglionic neuron cell bodies located?
A
In the lateral horns of the gray matter in the 12 thoracic segments in the first two lumbar segments of the spinal cord
15
Q
What’s the other name for the sympathetic division?
A
Thoracilumbar division
16
Q
What are the axons of the sympathetic preganglionic neurons known as?
A
Thoracolumnar outflow
17
Q
Where are the cell bodies of preganglionic neurons of the parasympathetic division located?
A
In the nuclei of four cranial nerves in the brain stem and in the lateral gray matter of the second through fourth sacral segments of the spinal cord
18
Q
What’s the parasympathetic division also known as?
A
Craniosacral division
19
Q
What are the axons of the parasympathetic preganglionic neurons referred to?
A
Craniosacral outflow
20
Q
What are the two major groups of autonomic ganglia?
A
- Sympathetic ganglia, components of the sympathetic division of the ANS
- Parasympathetic ganglia, components of the parasympathetic division of the ANS
21
Q
What are the two major sympathetic ganglia?
A
- Sympathetic trunk ganglia, also called (vertebral chain ganglia or paravertebral ganglia)
- Prevertebral (collateral) ganglia
22
Q
Sympathetic trunk ganglia
A
Primarily innervate Organs above the diaphragm such as the head, neck, shoulders, and heart
23
Q
Prevertebral ganglia
A
Interview organs below the diaphragm
24
Q
Where do preganglionic axons of the parasympathetic division synapse with postganglionic neurons?
A
Terminal ganglia
25
Where terminal ganglia located?
Within the walls of visceral organs
26
After axons of sympathetic preganglionic neurons pass sympathetic trunk ganglia what are the four ways they can connect with postganglionic neurons?
1. They can synapse with the ganglion they first reach
2. An axon me a sand or D sand to a higher or lower ganglion before synapsing with postganglionic neurons passing from ganglion to ganglion
3. An axon can continue without synapsing through the sympathetic trunk ganglion to end at the prevertebral ganglion and synapse with postganglionic neurons there
4. An axon may also pass without synapse even through the sympathetic trunk ganglion and a prevertebral ganglion on and then extend to chromaffin cells of the adrenal medullae that are functionally similar to sympathetic postganglionic neurons
27
Autonomic plexuses
Tangled networks Of axons of both sympathetic and parasympathetic neurons in the thorax, abdomen, and pelvis
28
Major plexuses in the thorax?
Cardiac plexus and pulmonary plexus
29
Cardiac plexus
Supplies the heart
30
Pulmonary plexus
Supplies the bronchial tree
31
The major plexuses of the abdomen and pelvis?
Celiac plexus, superior mesenteric plexus, inferior mesenteric plexus, hypogastric plexus, Renal plexus
32
Celiac plexus
Largest autonomic plexus surrounds the celiac trunk. distributed to the stomach, spleen, pancreas, liver, gallbladder, kidneys, adrenal medullae, testes, and ovaries
33
Superior mesenteric Plexus
Supplies the small and large intestine
34
Inferior mesenteric plexus
Innervates the large intestine also extends through the Hypogastric plexus
35
Hypogastric plexus
Anterior to the fifth lumbar vertebrae supplies the pelvic viscera
36
Renal plexus
Supplies the renal arteries within the kidneys and ureters
37
White ramus
A short pathway that the myelinated preganglionic sympathetic axons pass through
38
White Rami communicates
Structures containing sympathetic preganglionic axons that connect the anterior ramus of the spinal nerve with the ganglia of the sympathetic trunk
39
Sympathetic trunk ganglia
Arranged anterior and lateral to the vertebral column, one on either side.
Three cervical 11 or 12 thoracic four or five lumbar four or five sacral sympathetic trunk ganglia and one coccygeal ganglion on
40
Postganglionic neurons leaving the superior cervical ganglion serve what?
Head and heart
41
Post ganglionic neurons leaving the middle cervical ganglion and the inferior cervical ganglion inervate what?
Heart and blood vessels of the neck, shoulder, and upper limb
42
What are the four possible ways axons leave the sympathetic trunk?
1. They can enter spinal nerves
2. They can form cephalic Periarterial nerves
3. They can form sympathetic nerves
4. They can form splanchnic nerves
43
Gray rami communicantes
Structures containing sympathetic postganglionic axons that connects the gang we have the sympathetic trunk to spinal nerves
44
Cephalic Periarterial nerves
Nerves that extend to the head by wrapping around and following the course of various arteries the pass from the neck to the head provide sympathetic innervation to visceral factors in the skin of the face as well as other visceral factors of the head
45
Sympathetic nerves
Extend to visceral factors in the thoracic cavity provide sympathetic innervation to the heart and lungs
46
Sympathetic nerves to the heart
Axons of the postganglionic neurons exit the sympathetic trunk by forming sympathetic nerves enter the cardiac plexus to supply the heart
47
Sympathetic nerves to the lungs
Sympathetic nerves that enter the pulmonary plexus to supply the smooth muscle of the bronchi and bronchioles of the lungs
48
Splanchnic nerves
Sympathetic preganglionic axons pass through the sympathetic trunk without terminating in it and beyond the trunk they form these nerves would extend to outline prevertebral ganglia
49
Splanchnic nerves To abdominal pelvic organs
Most sympathetic preganglionic axons that enters the splanchnic nerves are destined to synapse with sympathetic postganglionic neurons in the prevertebral ganglia that supply the organs of the abdominal pelvic cavity
50
Splanchnic Nerves to the adrenal medulla
Some sympathetic preganglionic axons pass, without synapsing through the sympathetic trunk, grater splanchnic nerves and Celia ganglion and then extend to chromaffin cells
51
Chromaffin cells
Similar to sympathetic postganglionic neurons except the lock dendrites and axons rather than extend into another organ however the cells release hormones into the blood releasing a mixture of catecholamine hormones ( 80% epinephrin 20% nor epinephrin and trace amounts of dopamine)
52
Cell bodies of parasympathetic preganglionic neurons are found where?
Nuclei in the brainstem and in the lateral gray matter of the second through fourth sacral segments of the spinal cord
53
Cranial parasympathetic outflow
Consists of pre-ganglionic axons that extend from the brain stem in for cranial nerves
54
Sacral parasympathetic outflow
Consists of preganglionic axons in anterior roots of the second through fourth sacral spinal nerves
55
What are the four pairs of cranial outflow ganglia and the ganglia associated with the vagus 10 nerve
1. Ciliary ganglia - innervate smooth muscle fibres in the eyeball
2. PterygoPalatine ganglia - sends postganglionic axons to the nasal mucosa, palate, pharynx, and lachrymal glands
3. Submandibular ganglia - Send postganglionic axons to the submandibular and sub lingual salivary glands
4. Otic ganglia - Send postganglionic axons to the parotid salivary glands
56
Preganglionic axons that leave the brain is part of the biggest 10 nerves carry what amount of the total craniosacral outflow?
80%
57
Pelvic splanchnic nerves
Intervae smooth muscle in glands in the walls of the colon, ureters, urinary bladder, and reproductive organs
58
Cholinergic neurons
Release the neurotransmitter acetylcholine
59
In the ANS the cholinergic neurons include what?
1. All sympathetic and parasympathetic preganglionic neurons
2. Sympathetic postganglionic neurons that innervate most sweat glands
3. All parasympathetic postganglionic neurons
60
Two types of cholinergic receptors?
1. Nicotinic receptors
2. Muscarinic receptors
Both bind acetylcholine
61
Nicotinic receptors
Present in the plasma membrane of dendrites and cell bodies of both sympathetic and parasympathetic postganglionic neurons, the plasma membranes of chromaffin cells of the adrenal medullae, and in the motor end plate at the neuromuscular junction
62
Muscarinic receptors
Present in the plasma membranes of all the effectors (Smooth muscle, cardiac muscles, and glands) innervated by parasympathetic postganglionic axons
63
Adrenergic neurons
Releases norepinephrine
64
Adrenergic receptors
Find both norepinephrine and I’ve been a friend two main types are alpha receptors and beta receptors
65
Catechism-O-methyltransferase or monoamine oxidase
Enzymatically inactivates norepinephrine
66
Agonist
A substance that binds to an activate a receptor in the process mimicking the fact of a natural neural transmitter or hormone
67
Antagonist
Is a substance that binds to and blocks a receptor thereby preventing a natural neurotransmitter or hormone from exerting its effects
68
Autonomic tone
Regulated by the hypothalamus is a balance between sympathetic and parasympathetic activity
69
Effects of the fight or flight response
1. Pupils of the eyes dilate
2. Heart rate, force of heart contraction, and blood pressure increase
3. Airways dilate allowing faster movement of air into and out of the lungs
4. The blood vessels that supply the kidneys and the gastrointestinal tract constrict which decreases blood flow through these tissues that result in the slowing of urine formation and digestive activities which are not essential during exercise
5. Blood vessels that supply organs involved in exercise or fighting of danger-Skeletal muscles, cardiac muscle, liver, and Adipose tissue- Dilate, allowing greater blood flow through these tissues
6. Liver cells perform glycogenolysis (breakdown of glycogen to glucose) and adipose tissue cells perform Lipolysis (breakdown of triglycerides to fatty acids and glycerol)
7. Release of glucose by the liver increases blood glucose level
8. Processes that are not essential for meeting the stressful situation or inhibited for example muscular movement of the gastrointestinal tract and digestive secreation slow down or even stop
70
Why are sympathetic stimulation longer lasting and more widespread than the affects of parasympathetic stimulation?
1. Sympathetic postganglionic axons diverge more extensively as a result many tissues are activated simultaneously
2. Acetylcholinesterase quickly inactivates acetylcholine but norepinephrine lingers in the synaptic cleft for longer periods
3. Epi-nephron and norepinephrine secreted into the blood from the adrenal medulla intensify and prolong the response caused by norepinephrine liberated from the sympathetic postganglionic axons circulating through the body affecting all tissues that have alpha and beta receptors
71
“Rest and digest”, What are the five parasympathetic responses?
1. Lacrimation
2. salvation
3. urination
4. digestion
5. defaecation
72
“ Rest and digest” the 3 decreases
1. Decrease heart rate
2. Decrease diameter of airways (bronchoconstriction)
3. Decrease diameter (constriction) of the pupil’s
73
Autonomic (visceral) reflexes
Responses that occur when nerve impulses pass through an autonomic reflex ark play Keii role in regulating controlled conditions in the body such as blood pressure by adjusting heart rate force of ventricular contraction in blood vessel diameter
74
Components of the autonomic reflex arc
1. Sensory receptor
2. Sensory neuron
3. Integrating centre
4. Motor neurons
5. Effector
75
What is the major control in integration centre of the ANS?
Hypothalamus
76
Why are most parasympathetic preganglionic axons longer than most sympathetic preganglionic axons?
Because most parasympathetic ganglia are in the walls of visceral organs but most sympathetic ganglia are close to the spinal cord in the sympathetic trunk
77
What is the largest autonomic plexus?
Celiac (solar) plexus
78
Where does the pelvic splanchnic nerve branch to?
From the second through fourth sacral spinal nerves
