Neurons and Nervous System Quiz

Afferent nerves:

• provide O₂ to the efferent nerves.

• are exclusively within the central nervous system.

• are special non-myelinated nerves.

• deliver signals from the central nervous system.

• deliver signals to the central nervous system.

A synaptic terminal is located:

• between adjacent Schwann cells

• at the upstream end of a dendrite

• adjacent to the axon hillock

• at the downstream end of axon

• beside the voltage-gated Na* channels in axons

The Nodes of Ranvier are located:

• between adjacent Schwann cells

• at the upstream end of a dendrite

• adjacent to the axon hillock

• at the downstream end of axon

• beside the voltage-gated Na* channels in axons

In neurons of the central nervous system, the myelin sheath is produced by:

• action potentials

• vesicles released from the synaptic terminal

• synaptic cells

• Schwann cells

• oligodendrocytes

In a chemical synapse, the nervous signal travels across the synaptic gap:

• as ribosomes released from the pre-synaptic cell

• in vesicles

• in the form of neurotransmitters

• as an electrical signal

• in the form of ATP

Membrane potential is:

• the generation of a nervous signal at the dendrites

• the release of neurotransmitters into the synaptic cleft

• the slow diffusion of phospholipids and membrane proteins

• the ability of membranes to change shape

• the voltage across a membrane

The resting potential of an axon:

• varies according to the ion gradients across the nuclear envelope

• varies with the state of opening of the Na+ channels

• varies with the progression of the depolarization

• is ~-70mV

• is ~+70mV

An action potential is:

• a depolarization followed by a repolarization

• a hyperpolarization followed by a depolarization

• the release of neurotransmitters into the synaptic cleft

• the opening of ligand-gated channels

• the transport of Ca²+ out of a neuron by the Ca²+-ATPase

The action potential that travels down an axon is generated at:

• the nucleus in the cell body

• the Schwann cells

• the synapse

• the mitochondria in the axon

• the axon hillock

The depolarization that is part of the action potential is caused by:

• exocytosis of vesicles containing neurotransmitters

• activity of the Nat/K+-ATPase

• opening of Na+ channels

• opening of K+ channels

• opening of Ca²+ channels