Nervous System Quiz

Which of the following structures belongs to the peripheral nervous system:

• Cerebrum

• Brain stem

• Somatic sensory nerve

• Spinal cord

The part of the nerve responsible for receiving nerve impulse is

• The axon

• The nerve terminals

• The soma

• The dendrites

The myelinated nerve fiber has an outer layer of

• Nerve cells

• Schwann cells & myelin sheath

• Plasma cells

• Epithelial cells

About the excitability

• It is the ability of the living tissue to respond to a stimulus

• The most excitable tissues in the body are the red blood cells

• The chemical stimulation of the nerve is preferred to test the nerve excitability

• A stimulus with any strength and duration can cause nerve response.

About the membrane potentials

• It is the change difference between inside and outside of the membrane

• Action potential is produced by a subthreshold stimulus

• Local response occurs due to stimulation of the nerve with a threshold (adequate) stimulus

• There is an equal distribution of ions across the nerve membrane during rest

The main extracellular cation is

• Sodium

• Magnesium

• Calcium

• Potassium

The resting membrane potential of a nerve fiber

• Includes all the changes in membrane potential during conduction of the nerve impulse

• Is the potential difference between the inside and outside of the resting membrane

• Is always around zero

• Is due to the presence of negative ions on the outer surface of the membrane in relation to its inner surface

Which of the following about selective permeability is correct?

• The selective permeability of the membrane is responsible for the resting membrane potential

• Membrane permeability to Na+ is 20-100 times more than K+ during rest

• There is a passive K+ influx and passive Na+ efflux

• It is helped by voltage gated K+ channels

The Na+-K+ pump

• Is inactive at rest because the membrane is absolutely impermeable to sodium ions

• Is an example of passive transport

• Pumps 3 Na+ ion out of the nerve fiber and 2 K+ ions into the nerve fiber

• It does not require energy consumption or ATP usage

Voltage-gated channels are characterized by

• They are leaky channels

• They open or close by change in the membrane potential

• They open when a hormone or neurotransmitter binds to the channel

• They are responsible for resting membrane potential