Question

Which one of the following statements is true regarding excitatory neurotransmitters?

A. They open anion channels that depolarize the cell membrane and increase the likelihood of generating an action potential
B. They open cation channels that hyperpolarize the cell membrane and increase the likelihood of generating an action potential
C. They open cation channels that hyperpolarize the cell membrane and decrease the likelihood of generating an action potential
D. They open anion channels that hyperpolarize the cell membrane and decrease the likelihood of generating an action potential
E. They open cation channels that depolarize the cell membrane and increase the likelihood of generating an action potential

Answer 1

The true statement about excitatory neurotransmitters is that they open cation channels leading to depolarization of the neuron's membrane, increasing the likelihood of generating an action potential.

Step-by-step explanation:

When excitatory neurotransmitters bind to receptors on a neuron's dendrites, they cause ligand-gated cation channels to open, allowing positive ions like Na+ to enter the neuron. This influx of positive ions leads to a depolarization of the neuron's membrane, which reduces the voltage difference between the inside and outside of the neuron. If the membrane depolarizes to the threshold potential, an action potential is triggered, and the neuron transmits this electrical signal along its axon to communicate with other neurons.