Test 2 Study Guide 2

Question 1

How many cranial nerves arise from the forebrain?

How many from the midbrain and hindbrain?

Answer 1

2

10

Question 2

SAME DAVE:

Answer 2

Sensory Afferent Motor Efferent. Dorsal Afferent Motor Efferent

Question 3

Mixed nerves:
Sensory nerves:
Motor nerves:

Answer 3

Most nerves are mixed
Olfaction, eyesight and other special senses are purely sensory.
No nerves are only motor, but some are predominately motor

Question 4

There are 31 pairs of spinal nerves:

• Cervical:
• Thoracic:
• Lumber:
• Sacral:
• Coccygeal:

Answer 4

• Cervical: 8
• Thoracic: 12
• Lumber: 5
• Sacral: 5
• Coccygeal: 1

Question 5

How many nerves are involved in a normal reflex arc?

Answer 5

3 (sensory, association neurons, motor)

Question 6

How is the knee jerk reflex different from most nerve arcs?

Answer 6

Monosynaptic reflex

It only involves a sensory and motor nerve tract.

Question 7

Reflexes proceed sensation by the brain

Answer 7

True

Question 8

Visceral define:

Answer 8

Within the body

Question 9

Where are somatic cell bodies located?

Answer 9

They are all in the CNS (no motor ganglia)

Question 10

How many neurons are in the efferent pathway for:

• Somatic:
• Autonomic:

Answer 10

1

2

Question 11

How does the autonomic nervous system conduct efferent firing (all of it will be efferent firing):

Answer 11

Preganglionic cell will activate a post ganglionic cell using nicotinic Ach receptors (always)
Postganglionic cell can use a variety of different neurotransmitters

Question 12

How do autonomic reflexes work?

Answer 12

Same as somatic, 2 synapse reflexes

Question 13

Which nerve is the ninth cranial nerve

Answer 13

Glossopharyngeal nerve

Question 14

The glossopharyngeal and vagus nerve are both mixed nerves. What does this mean?

Answer 14

They also bring sensory information, for example blood pressure, plasma pH and oxygen information

Question 15

Somatic vs Autonomic nerves:

• What happens to the muscle when the nerve is cut?
• Ach

Answer 15

Somatic go flaccid.
Autonomic still can retain tension and sometimes functionality (they also undergo denervation sensitivity)

Nicotinic, always excitatory for muscles. Muscuranic (or nicotonic), not always excitatory for autonomic

Question 16

The heart can function automatically (pacemaker within it) how do autonomic nerves effect organs such as this?

Answer 16

They increase or decrease its pace.

Question 17

Craniosacro division:

Thoracolumbar division:

Answer 17

Craniosacro division:
Parasympathetic
Thoracolumbar division:
Sympathetic (heart is in the thorax, thoracolumbar) (the adrenal gland is located with the thoracolumbar region, activation of the adrenal gland is tied to sympathetic)

Question 18

Thoraco lumbar division:

• location of the ganglia:
• Nomenclature of ganglia:

Answer 18

- location of the ganglia:
Sympathetic ganglia are normally located parallel to the spinal cord, on both sides of the spinal column 
- Nomenclature of ganglia:
* Sympathetic chain of Ganglia
Paravertebral Ganglia

Question 19

Rami Communicantes:

• Gray:
• White:

Answer 19

• Gray:
  Unmyleinated post-ganglionic sympathetic axons which leave the autonomic (sympathetic ganglion) from the sympathetic chain of ganglia and regions the spinal nerve
• White:
  Myelinated preganglionic sympathetic axons which depart the spinal nerve to enter the sympathetic ganglia. These nerves can travel up the sympathetic chain of ganglia up to synapse with their postganglionic cell.

Question 20

What is a ramus or rami?

Answer 20

A branch or a part which splits apart

Question 21

Explain how convergence and divergence relate to sympathetic ganglia?
What effect is caused by this?

Answer 21

Pre-ganglionic neurons synapse with multiple post-synaptic neurons (this can be both up, down, or at the same point in the sympathetic chain of ganglia.
Post-ganglionic neurons are also receiving receiving input from multiple pre-ganglionic neurons.
Mass activation
: allows integration of the system, so activation causes activation of the entire system. Which is always activated to some extent but can become more active by individual signals.

Question 22

Splanchnic means:

Answer 22

Relating to the viscera.

Question 23

How do splanchnic nerves differ from the normal behavior?

What are the three ganglion within which splanchnic nerves synapse?

Answer 23

Splanchnic nerves still take the white rami communicatus into the sympathetic ganglionic chain, however they keep going right through it and instead synapse within…
The celiac, superior mesentaric or inferior mesenteric ganglia.

Question 24

One splanchnic nerve does not go to a ganglion. What does this splanchnic nerve go to?

Answer 24

This nerve goes to the adrenal medulla.

Question 25

Define the Sympathoadrenal system:

Answer 25

Because of mass activation the sympathetic nervous system will activate their effector cells at the same time that the adrenal medulla will produce predominately epinephrine and some norepinephrine

Question 26

What are the implications of parasympathetic nerves not traveling with the spinal nerves?

Answer 26

They do not reach cutaneous effectors (blood vessels, sweat glands, arrector pili) and blood vessels in the muscle system. (these recieve only sympathetic stimulation.

Question 27

Four of the cranial nerves contain preganglionic parasympathetic fibers: they are? - How is the tenth cranial nerve different from the other four?

Answer 27

III oculomotor VII facial IX glossopharyngeal X vagus Vagus does not synapse solely in the head but goes to widespread regions in the body.

Question 28

Describe how the use of parasympathetic axons in the oculomotor nerve work.

Answer 28

Oculomotor nerve is the 3rd cranial nerve. Preganglionic fibers synapse with postganglionic within the ciliary ganglion. The post ganglionic nerve stimulates the constrictor muscle of the iris, and causes a contraction of the eye.

Question 29

How do you remember that parasympathetic constricts the eye?

Answer 29

Constriction of the eye reduces light, and you need less light in relaxed state. During an alert state you will need a lot of light.

Question 30

Where is the cell body of the paired vagus nerves?

Answer 30

The medulla.

Question 31

Do parasympathetic or sympathetic nerves have longer preganglionic axons?

Answer 31

Parasympathetic, as the nerves from the craniosacral division must reach the terminal ganglia located next to the effector organs.

Question 32

Effector cells of both the parasympathetic and sympathetic nervous system are always governed by postganglionic axons with what exception?

Answer 32

Pregonglionic innervation of the adrenal medulla

Question 33

What neurotransmitter is released by the sympathetic postsynaptic ganglia? What neurotransmitter is released by the parasympathetic postsynaptic ganglia?

Answer 33

Sympathetic: Norepinphrine (adronergic) Parasympathetic: Acetylcholine, muscurinic receptors (cholinergic)

Question 34

Varicosity:

Answer 34

A swelling in the axon of a post-ganglionic neuron. These varicosities for synapses in passing (synapses en passant).

Question 35

Synapses in passant: - Define: - explain how it works in tissue:

Answer 35

- Define: Synapsis in passing (refers to varicosities) - explain how it works in tissue: Sympathetic and parasympathetic synapsis in passing occurs often on the same cells. These neurons will often have antagonistic effects.

Question 36

What are the types of adronergic receptors: | Define adronergic receptors:

Answer 36

``` Alpha1: Alpha2: Beta1: Beta2: Adronergic receptors bind norepinephrine or epinephrine, both produces by the adrenal gland (thus adronergic) ```

Question 37

What type of receptors are adrenergic receptors? | Are adrenergic receptors specific to norepinephrine or epinephrine?

Answer 37

G protein-coupled receptors | It appears they can bind both.

Question 38

Alpha 2 receptors: | - Locale and general functionality:

Answer 38

Different subtypes exist. One subtype is located on pre-synaptic neurons (alpha-1 is on post-synaptic neurons), release of norepinephrine activates both alpha-1 and alpha-2, but alpha-2 activation inhibits release of norepiniphrine from the presynaptic neuron acting as a negative feedback loop.

Question 39

What drug acts as an adronergic alpha-2 agonist? | What is the effect of this?

Answer 39

Clonidine Clonidine stimulates alpha-2 receptors in the brain, which acts to reduce release of norepiniphrine related to parasympathetic (and possibly other) responses in the brain. This lowers your blood pressure. Clonidine relaxes the entire sympathoadrenal system.

Question 40

What is the second messenger used by: beta receptors: Alpha-1 receptors:

Answer 40

beta receptors: cAMP Alpha-1 receptors: Ca2+

Question 41

What do Alpha-1 receptors do:

Answer 41

Associated with constriction, usually of smooth muscle: - Often constrict vascular/smooth muscle * - constriction of skin and visceral vessels (reduce blood flow to skin and internal organs) * - Sphincters constrict and slow the passage of food in small intestine * - Radial fibers of iris constrict, dialating the eyes. - Helps in secretion of glucose and glycogenolysis from the liver

Question 42

What do Beta-1 receptors do:

Answer 42

Increase heart rate and contraction strength

Question 43

What do Beta-2 receptors do:

Answer 43

Associated with relaxation of smooth muscles - arterioles dilate - Bronchioles dilate do to smooth muscle relaxation - Glycogen release

Question 44

Can sympathetic nerves cause relaxation? | - Examples:

Answer 44

Yes | Lungs relax, some blood vessels

Question 45

Can Parasympathetic nerves cause excitation? | - Examples:

Answer 45

Yes | Stomach contractions

Question 46

Parasympathetic ganglia which are located next to, or within their effector organ.

Answer 46

Terminal Ganglia