PHYSIOLOGY
EXCITATION CONTRACTION COUPLING
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
Which of the following does NOT happen when the action potential reaches the synaptic terminal?
|
|
Exocytosis of ACh into the synaptic cleft occurs
|
|
|
Potassium ions flood the intercellular space.
|
|
|
The action potential generated at the motor end plate sweeps across the entire membrane surface.
|
|
|
Vesicles in the synaptic terminal fuse with the membrane of the neuron.
|
Explanation:
Detailed explanation-1: -As the action potential passes through, potassium channels stay open a little bit longer, and continue to let positive ions exit the neuron. This means that the cell temporarily hyperpolarizes, or gets even more negative than its resting state.
Detailed explanation-2: -The action potential causes neurotransmitters to be released at the end of the axon, which can subsequently influence other neurons. Incorrect option D: Action potentials travel in both directions, meaning that they can flow either up or down the axon.
Detailed explanation-3: -The flow of potassium ions out of the cell results in a decrease in membrane potential towards the cell’s resting voltage.
There is 1 question to complete.