Bio 203 Objectives

Objectives lecture 20 – note that this material will be on the Final exam, NOT on exam 2

1. Name the three branches of the autonomic nervous system.

Sympathetic, parasympathetic, and enteric

2. Describe in a diagram the basic differences (including the occurrence of ganglia) between the autonomic nervous system and the somatic nervous system.

2b. State the 3 locations where acetylcholine is a neurotransmitter.

Cholinergic neurons, nicotinic receptors, muscarinic receptors

3. Describe the discovery and chemical identification of “vagusstoff” = acetylcholine (inlcude the names of the scientists involved Loewi, Dale).

Was discovered by Otto Loewi in Vienna and chemically identified by Sir Henry Dale in England. In Loewi’s experiment in 1921, he placed two beating hearts in separate chambers. Ringer’s solution flowed through the first chamber into the second. When the vagus nerve to the first heart was electrically stimulated, the first heart slowed down. After a delay, Loewi observed that the second heart also slowed down. This demonstrated that a substance released by vagus nerve stimulation was carried to the second heart. Loewi called it Vagusstoff. Dale characterized it chemically as acetylcholine. They shared the Nobel Prize in physiology or medicine in 1936.

4. List the groups of autonomic ganglia, and state which division of the autonomic nervous system they are associated with.

Paravertebral ganglia- sympathetic division

Collateral ganglia- sympathetic division

Terminal ganglia- parasympathetic division

5. Draw the origins and pathways of pre- and postganglionic fibers in the sympathetic branch of the autonomic nervous system.

6. Draw the origins and pathways of pre- and postganglionic fibers in the cranial and sacral divisions of the parasympathetic (don’t forget the cranial nerves and the ganglia associated with them).

7. Give a...