4 Which of the following directly or indirectly determines the amount of neurotransmitter released at the a› terminal of the sensory neuron?

Question

• The strength of the stimulus applied to the sensory receptor.
• The frequency of action potential at the sensory receptor.
• The amount of calcium that enters the sensory receptor.
• All of the above play a role in determining the amount of neurotransmitter released.

Answer 1

The correct answer is: All of the above play a role in determining the amount of neurotransmitter released.

Here's a brief explanation of how each factor contributes:

1. The strength of the stimulus applied to the sensory receptor: A stronger stimulus can lead to a greater depolarization of the sensory neuron, which can increase the likelihood of generating action potentials.

2. The frequency of action potentials at the sensory receptor: A higher frequency of action potentials can lead to more frequent opening of voltage-gated calcium channels at the axon terminal, resulting in increased calcium influx and therefore more neurotransmitter release.

3. The amount of calcium that enters the sensory receptor: Calcium ions play a crucial role in the release of neurotransmitters from the presynaptic terminal. More calcium entering the terminal typically leads to more neurotransmitter being released.

Thus, all these factors interact to influence neurotransmitter release at the sensory neuron terminal.