1. PART 5 THE Autonomic Nervous system
Unit 3 Communication and Control

2. Nervous System Divisions

3. A. INTRODUCTION

4. The Autonomic Nervous System
Autonomic = visceral
A subdivision of the PNS
Sympathetic, parasympathetic and enteric divisions
Regulates
Glands
Smooth muscle
Cardiac muscle
ANS activities are automatic (involuntary)

5. iCLICKER
Your client is prescribed a medication that targets the autonomic nervous system. Which effector will NOT be directly affected?
Cardiac muscle
Glands
Smooth muscle
Skeletal muscle

6. Review of SNS Voluntary and reflexive movements
If somatic neurons stop = all communication with effector stops

7. The Autonomic Nervous System
ANS components similar to those in SNS
Sensory Receptor
(intero, chemo, mechano)
Autonomic
Sensory Neuron
Integrating Center
Effector
Autonomic (preganglionic)Motor Neuron
Autonomic (postganglionic) Motor Neuron
Table 15.1

8. iCLICKER
How many neurons are in an autonomic motor pathway ? 1 2 3 4

9. ANS Focuses on Efferent System
Autonomic pathways = two motor neurons connecting SC  effector
Preganglionic Motor Neuron
SC or brainstem (cell body)  ganglion
Myelinated
Postganglionic Motor Neuron
Ganglion (cell body)  effector
Unmyelinated
NOTE: SNS has uninterrupted synapse

10. B. ANATOMY OF THE ANS Most organs have dual innervation INTRODUCTION
Body movement results from alternating contraction (shortening) and relaxation of muscles; the skeletal system provides leverage and a supportive framework for this movement.
Most organs have dual innervation

11. Sympathetic Nervous System

12. Sympathetic Nervous System
Autonomic
motor neurons
Spinal cord
Autonomic
ganglion
Sympathetic preganglionic neuron (myelinated)
Sympathetic postganglionic neuron (unmyelinated)
Effectors: glands, cardiac muscle, smooth muscle (e.g., in urinary bladder)

13. Sympathetic Nervous System
Exception to typical SANS system

14. Sympathetic Chains

15. Sympathetic Ganglia Right sympathetic trunk ganglion CELIAC GANGLION
SUPERIOR MESENTERIC
GANGLION
INFERIOR MESENTERIC
GANGLION
Right sympathetic
trunk ganglion
Anterior view

16. Figure 15.2 Structure of the Sympathetic ANS

17. iCLICKER Which nerves carry sympathetic motor output? cranial nerves
spinal nerves
cranial nerves and spinal nerves

18. iCLICKER
Which neurotransmitter is released by sympathetic postganglionic neurons?
acetylcholine
epinephrine
norepinephrine
both b) and c)

19. Parasympathetic Nervous System

20. Parasympathetic Nervous System
Autonomic ganglion
ACh
Spinal cord
Parasympathetic preganglionic neuron (myelinated)
Parasympathetic postganglionic neuron (unmyelinated)
Effectors: glands, cardiac muscle, smooth muscle

21. Terminal ganglia

22. Figure 15.3 Structure of the Parasympathetic ANS

23. iCLICKER Which nerves carry parasympathetic motor output?
cranial nerves
spinal nerves
cranial nerves and spinal nerves

24. iCLICKER
Which neurotransmitter is released by parasympathetic postganglionic neurons?
acetylcholine
epinephrine
norepinephrine
both b) and c)

25. Enteric Nervous System
Nerves & ganglia
Wall of GI tract, pancreas, gallbladder
GI tract needs to respond to environmental stimuli to fnc (like skin)
ENS usually fnc independently from CNS

26. ANS Receptors

27. ANS Receptors

28. iCLICKER
Which receptor is found on effector cells of the parasympathetic nervous system?
alpha
beta
muscarinic
nicotinic

29. C. PHYSIOLOGY OF THE ANS

30. Autonomic Reflexes Interoreceptor Sensory Neuron PreganglionicNeuron
Integrating Center
Effector
Postganglionic Neuron

31. Pupillary Light Reflex

32. Pupillary Light Reflex

33. The Effect of Higher Brain Centers on ANS Functions

34. D. FUNCTIONS OF THE ANS

35. Sympathetic Responses
Four Es

36. Parasympathetic Responses
SLUDD