QuestionSBA
QuestionChoice
Calcium ions are not primarily responsible for the depolarisation phase of the action potential. They play a significant role in synaptic transmission and various cellular processes but are not the key ions involved in the rising phase of the action potential.
10024008
d
Calcium (Ca2+)
QuestionChoice
Magnesium ions are not involved in the depolarisation phase of the action potential. Magnesium primarily serves as a cofactor in enzymatic reactions and does not play a significant role in the ionic mechanism of action potentials.
10024009
e
Magnesium (Mg2+)
QuestionChoice
In a typical neuron, the depolarisation phase of an action potential is primarily driven by the influx of sodium ions (Na+) through voltage-gated sodium channels. This influx of positive sodium ions into the cell leads to a rapid change in membrane potential, creating the rising phase of the action potential.
10024005
a
Sodium (Na+)
QuestionChoice
Chloride ions do play a role in the action potential, but they are primarily responsible for the hyperpolarisation phase (falling phase) and the maintenance of the resting membrane potential. They are not responsible for the initial depolarisation.
10024006
b
Chloride (Cl-)
QuestionChoice
Potassium ions do play a role in the repolarisation and hyperpolarisation phases of the action potential. They are responsible for returning the membrane potential to its resting state and maintaining it. They are not the ions responsible for the initial depolarisation.
10024007
c
Potassium (K+)
Concept
Chapter
2693
5716
Ionic Mechanism of Action Potentials
Topic
280
Nerves
17199
What ion is primarily responsible for the depolarisation phase (rising phase) of an action potential in a typical neuron?
a