Autonomic Nervous System

Question 1

Understand the structural and functional differences between the parasympathetic and the sympathetic nervous systems.

Answer 1

Two major divisions; the Central Nervous System (CNS) and the Peripheral Nervous System.

Peripheral:
- includes all the nerves and ganglia outside of the brain and spinal cord, that is outside the CNS.

• includes both afferent neurons (sensory nerves that projects to the brain/spinal cord) and efferent neurons (motor nerves that carry motor commands away from brain/spinal).
• is further divided into the Somatic Nervous System and the Autonomic NervousSystem (ANS). The ANS, as implied by the name, functions autonomously or without an individual’s conscious effort. As such, the intrinsic processes that keep you alive (e.g. breathing, digesting) are regulated by the ANS.

Question 2

Explain how organs respond to the flight or fight response.

Answer 2

sympathetic nervous system activated:
- eyes dilate,
- heart rate increases
- less salivation
- reduced bladder action and digestive

blah blah

Question 3

Describe using a simple diagram of the general circuitry between the sensory receptors and effector receptors.

Answer 3

diagram in onenote

• the message is received as a signal by the sensory neurons
• transmits message to CNS (spinal chord etc)
• sends to ganglia via pre ganglionic neuron (motor neuron)
• post-ganglionic neuron (motor neuron) sends info from ganglia to effector for a response

Question 4

Understand the difference between pre- and post-ganglionic nerves in the ANS.

Answer 4

pre are short
post are long

Question 5

Define a ganglia.

Question 6

Explain the difference between boutons and varicosities.

Answer 6

1. Axon terminals, or synaptic or terminal “boutons”, are small swellings found at the terminal ends of axons where synapses occur with other cells/neurons.
2. These post-ganglionic axons terminate on the effector organ in these ‘strings of beads’ known as varicosities.

There are two distinct kinds of smooth visceral muscles:

Single-unit smooth muscle cells
Multi-unit smooth cells.
Single-unit smooth muscle cells, like those that line the walls of the gastrointestinal tracts, are coupled by gap junctions; enabling electrical signals to be propagated to adjacent cells. Not all cells are innervated by sympathetic varicosities, but those that are can rapidly spread the signal to adjacent cells; resulting in synchronized depolarization and contraction as a single unit.

Multi-unit smooth muscles, like those in your eyes, are not linked together by gap junctions. As such, each smooth muscle cell must be individually innervated.

Question 7

Understand the mechanisms involved in neurotransmitter release.

Answer 7

?

Question 8

Describe the sequence of events in parasympathetic AND sympathetic neurotransmission, from transmitters to receptors.

Answer 8

?

Question 9

Explain how different cholinergic and adrenergic receptors give rise to specific physiological effects in different organs

Answer 9

?