ABEM ABEM Anatomy & Neurophysiology

Question 1

Which ion channel is primarily responsible for the upstroke of a nerve action potential?

Accepted Answer

Voltage-gated sodium channels

Answer

Voltage-gated potassium channels

Answer

Ligand-gated calcium channels

Answer

Chloride leak channels

Question 2

The anterior interosseous nerve is a branch of which major nerve?

Accepted Answer

Median nerve

Answer

Ulnar nerve

Answer

Radial nerve

Answer

Musculocutaneous nerve

Question 3

What is the resting membrane potential of a typical mammalian motor neuron?

Accepted Answer

-70 mV

Answer

-30 mV

Answer

-90 mV

Answer

+40 mV

Question 4

Which structure forms the myelin sheath in the peripheral nervous system?

Accepted Answer

Schwann cells

Answer

Oligodendrocytes

Answer

Astrocytes

Answer

Microglia

Question 5

The dorsal interossei muscles of the hand are innervated by which nerve?

Accepted Answer

Ulnar nerve

Answer

Median nerve

Answer

Radial nerve

Answer

Anterior interosseous nerve

Question 6

At a node of Ranvier, the action potential jumps from one node to the next in a process called:

Accepted Answer

Saltatory conduction

Answer

Continuous conduction

Answer

Ephaptic transmission

Answer

Antidromic conduction