Lecture 2 - The Nervous System And Drugs

Question 1

What are the components of the CNS?

Answer 1

Brain & spinal cord

Question 2

What are the 3 divisions of the PNS?

Answer 2

1. Somatic NS
2. Sensory NS
3. Autonomic NS

Question 3

What are the 2 major types of specialised cell in the NS?

Answer 3

Neurones
Glia (neuroglia)

Question 4

What are the 2 divisions of the autonomic NS?

Answer 4

1. Sympathetic
2. Parasympathetic

Question 5

What does the autonomic NS control?

Answer 5

Involuntary actions
(e.g. HR / BP / filtration of blood by kidneys / digestion)

Question 6

What type of protein is the myelin sheath?

Answer 6

Lipoprotein

Question 7

What are the roles of glial cells?

Answer 7

Support

Communication

Question 8

What is the purpose of keeping Na+ ions out of equilibrium across the cell membrane?

Answer 8

Na+ ions used to produce transient change in the membrane potential

Generating an action potential

Question 9

What is the normal direction of impulse in a neurone?

Answer 9

From the dendrites to the soma to the axon terminals

Question 10

What is the net gradient of Na+ ions?

Answer 10

Net gradient into the cell

Due to conc & electrical gradient into the cell

Question 11

What is the Nernst / equilibrium potential?

Answer 11

Approximately = to membrane potential (~ -70mV)

Question 12

What is the difference between the Schwann cells in myelinated and unmyelinated neurones?

Answer 12

Unmyelinated - 1 Schwann cell can support multiple different axons

Myelinated - several Schwann cells insulate 1 axon

Question 13

What does the somatic NS control?

Answer 13

Skeletal muscle contraction (i.e. limbs)

Question 14

What does the sensory NS control?

Answer 14

Skin

Viscera (i.e. heart, kidneys, gut)

Question 15

What controls ion movement across the neuronal cell membrane?

Answer 15

Voltage-gated ion channels that span the membrane