Unit 4 Lecture 32

Question 1

What are the 3 parts to the Peripheral Nervous System?

Answer 1

Somatic, autonomic and enteric nervous system

Question 2

Describe the somatic nervous system

Answer 2

• somatic sensory (voluntary) ascend to CNS

- somatic motor (voluntary) descend to SKELETAL MUSCLE in PNS

Question 3

Describe the autonomic nervous system

Answer 3

• autonomic sensory (involuntary) ascend to CNS

- autonomic motor (involuntary) descend into ENTERIC NS or SMOOTH MUSCLE, CARDIAC MUSCLE and GLANDS

Question 4

Why do we need the autonomic ns?

Answer 4

maintains breathing and cardiovascular function w/out consciousness (sleeping etc)

Question 5

How does the autonomic ns opperate?

Answer 5

• uses reflex arcs

- its controlled by centers in the hypothalamus and brain stem

Question 6

What is the difference between the somatic and autonomic ns?

Answer 6

Autonomic:

• Effectors - cardiac muscle, smooth muscle, and glands
• involuntary
• 2 efferent neurons exit CNS

Somatic:

• Effectors- skeletal
• Voluntary
• 1 efferent neuron exits CNS

Question 7

What are the 2 parts of the autonomic nervous system?

Answer 7

Sympathetic and parasympathetic

Question 8

Define the sympathetic ns

Answer 8

fight or flight

Question 9

Define the parasympathetic ns

Answer 9

rest or digest

Question 10

Where do efferent neurons leave the SC in the somatic ns?

Answer 10

anterior horn (somatic motor)

Question 11

Where do efferent neurons leave the SC in the autonomic ns?

Answer 11

lateral horn (visceral motor)

Question 12

Name the first efferent neuron from the autonomic ns

Answer 12

Preganglionic neuron

Question 13

What happens after the first efferent neuron leaves the CS

Answer 13

It synapses with another efferent neuron in a ganglion -> 2nd efferent neuron

Question 14

name of the 2nd efferent neuron in autonomic ns

Answer 14

postganglionic neruon

Question 15

Define ganglion

Answer 15

sensory cell bodies in the PNS

Question 16

Where are most ganglia found?

Answer 16

near the spinal cord

Question 17

Define thoracolumbar

Answer 17

preganglionic neurons begin in T1 and L2 regions

Question 18

What are 3 types of sympathetic ns ganglia

Answer 18

1. sympathetic trunk (chain)
2. Prevertebral ganglia (collateral)
3. Adrenal medulla

Question 19

Describe the sympathetic trunk (chain)

Answer 19

paired ganglia near spinal cord

Question 20

What does the postganglionic neuron of the sympathetic trunk innervate?

Answer 20

Visceral organs in thoracic cavity

Question 21

Describe the prevertebral ganglia (collateral)

Answer 21

Anterior to vertebral bodies

Question 22

What does the postganglionic neuron of the prevertebral ganglia innervate?

Answer 22

abdominopelvic organs

Question 23

Describe the adrenal medulla

Answer 23

acts as a modified sympathetic ganglion

Question 24

What do postganglionic neurons in the adrenal medulla do?

Answer 24

• they are short

- release NOREPINEPHRINE (20%) and EPINEPHRINE (80%) into blood stream

Question 25

What are norepinephrine and epinephrine called

Answer 25

catecholamines

Question 26

What makes up the sympathetic trunk?

Answer 26

3 cervical, 11 thoracic, 4 lumbar, and 4 sacral

Question 27

What makes up the prevertebral ganglia?

Answer 27

celiac ganglion, superior mesenteric ganglion, and inferior mesenteric ganglion

Question 28

Define neurotransmitter

Answer 28

A chemical transmitter released by neurons to stimulate neighboring neurons/cells

Question 29

Describe the neurotransmitter process of the sympathetic ns

Answer 29

1. preganglionic neurons release ACETYLCHOLINE (ACh) 2. Binds to nicotinic cholinergic receptors on postganglionic cell body 3. Postganglionic neurons release NOREPINEPHRINE (NE) 4. Binds to adrenergic receptor on effector cell

Question 30

What are the two special cases of neurotransmitters?

Answer 30

Sweat glands and adrenal medulla

Question 31

Describe sweat glands as a neurotransmitter

Answer 31

- Preganglionic neurons release ACh -> binds **** SAME | - postganglonic neurons release ACh (NOT NE) at the effector -> binds to muscarinic cholinergic receptors at sweat gland

Question 32

Describe adrenal medulla as a neurotransmitter

Answer 32

- Pregang. releases ACh - Chromaffin cells act as postgang. neurons & adrenal medulla acts as a modified ganglion - Chromaffin cells release Epinephrine and NE into blood

Question 33

When is NE a neurotransmitter?

Answer 33

When it is released from sympathetic nerve endings directly at target tissues (short lived)

Question 34

When is NE is a hormone

Answer 34

When it is released from the adrenal gland into the blood stream (longer lasting effects)

Question 35

What is epinephrine?

Answer 35

Hormone - bc it is released from the adrenal gland into the blood Adrenaline

Question 36

Define adrenergic receptors

Answer 36

Things that bind epinephrine (adrenaline) and norepinephrine (noradrenaline) at effector tissues

Question 37

What are the 2 types of adrenergic receptors?

Answer 37

1. Alpha adrenergic receptors | 2. Beta adrenergic receptors

Question 38

Define Alpha adrenergic receptors

Answer 38

- found in smooth muscle of arterioles, bladder | - results in CONSTRICTION

Question 39

Define beta adrenergic receptors

Answer 39

- found in heart, bronchioles, liver | - causes INCREASED METABOLISM

Question 40

What is the goal of fight or flight

Answer 40

to increase mental alertness, energy availability (glucose) and ability to handle stress

Question 41

What are specific responses to the sympathetic ns?

Answer 41

- mobilize fuels - redistribution of blood flow - decrease urinary output and digestive functions - Increase heart rate and blood pressure - Increase activity of sweat gland - increase diameter of bronchioles - dilation of pupils