Neuronal Communication and Neurotransmitter Functions

Neurons communicate through neurotransmitters, which are released when an action potential reaches the nerve terminal. These neurotransmitters bind to receptors on neighboring neurons, transmitting signals. Neurotransmitters are classified by their chemical structure, including amino acids, neuropeptides, monoamines, and acetylcholine. They are stored in synaptic vesicles and released via exocytosis. Their effects can be excitatory or inhibitory, depending on the receptor. Neurotransmitters are recycled or degraded to prevent overstimulation.

What is the primary method by which neurons communicate with each other?

• Magnetic fields

• Optical signals

• Chemical messages

• Electrical impulses

Which type of synapse involves a connection between an axon and a dendrite?

• Axosomatic

• Axoaxonic

• Dendrodendritic

• Axodendritic

Which neurotransmitter is classified as a monoamine?

• Acetylcholine

• Glutamate

• GABA

• Dopamine

What triggers the release of neurotransmitters from synaptic vesicles?

• Sodium influx

• Magnesium influx

• Potassium efflux

• Calcium influx

What is the process called when neurotransmitters are released into the synaptic cleft?

• Phagocytosis

• Pinocytosis

• Exocytosis

• Endocytosis

Which neurotransmitter is primarily excitatory and increases the likelihood of action potentials?

• Glutamate

• Histamine

• Serotonin

• GABA

How does GABA affect the postsynaptic cell?

• It depolarizes the cell

• It hyperpolarizes the cell

• It has no effect

• It causes the cell to release more neurotransmitters

What role does acetylcholine play at neuromuscular junctions?

• Inhibits muscle contraction

• Stimulates muscle contraction

• Inhibits heart rate

• Stimulates digestion

What happens to neurotransmitters after they bind to their receptors?

• They are converted into hormones

• They are permanently bound

• They diffuse away and are recycled

• They are degraded immediately

Which mechanism is NOT involved in the removal of neurotransmitters from the synaptic cleft?

• Active transport into the postsynaptic cell

• Degradation by enzymes

• Diffusion into nearby astrocytes

• Reuptake