Nervous System

What is the role of Schwann cells in neurotransmission?

•  Thermal insulation of neuronal axons
• Limit the speed of the action potential
• Enhance the speed of the action potential
• Protect the neuronal soma from trauma

The opening of axon membrane voltage-gated potassium channels is responsible for which part of the action potential?

• Depolarisation of the membrane
• Repolarisation of the membrane
• Contraction of the post synaptic muscle fibre
• Signalling vesicular release of neurotransmitters

The nervous system is divided into the ______ and the ______; the former consists of ______; the latter______.  

• ANS; PNS; the nerves around the body; the ventricles
• ANS; CNS; the nerves around the body; the brain and spinal cord
• CNS; PNS; the nerves around the body; the ventricles
• CNS; PNS; the brain and spinal cord; the nerves around the body

The brain's supporting cells are called: 

• glia
• mitochondria
• neurons
• nuclei

______ send signals away from neurons whereas ______ receive signals from other neurons. 

• dendrites; axons
• axons; dendrites
• synapses; dendrites
• axons; synapses

If the stimulation of a cell is strong, the strength of the action potential produced would be: 

• Twice that produced by weak stimulation 
• Stronger than that produced by weak stimulation
• Weaker than that produced by weak stimulation
• No different to that produced by weak stimulation

When the cell becomes permeable to sodium, the charge changes to ______; this is called ______.  

• -55mV; depolarisation
• -70mV; repolarisation
• -55mV; hyperpolarisation
• -70mV; hyperpolarisation

When the neuron expels potassium:  

• The inside of the cell loses negative ions and produces a negative charge inside
• The inside of the cell loses positive ions and produces a negative charge inside
• The inside of the cell loses negative ions and produces a positive charge inside
• The inside of the cell loses positive ions and produces a positive charge outside

When the charge across the membrane of a neuron is about ______, the charge is called the ______. This is because there are ______.  

• -70mV; resting potential; more positive ions inside the cell
• -100 mV; action potential; more positive ions inside the cell 
• -60 mV; action potential; more negative ions inside the cell 
• -70mV; resting potential; more negative ions inside the cell

Neurons communicate with each other by sending electrical impulses called:  

• Action potentials 
•  Membrane potentials
• Neuromodulators
• Neurotransmitters