Signal transduction is defined as which?

Signal transduction is defined as which?

• A. The synthesis of neurotransmitters in vesicles
• B. The release of neurotransmitters into the synaptic cleft
• C. The degradation of neurotransmitters by enzymes
• D. The conversion of a chemical signal (neurotransmitter) into an intracellular response via specific receptors

Answer: (D)

Signal transduction is the process by which an extracellular chemical signal, such as a neurotransmitter, binds to a specific receptor on the target cell and is converted into an intracellular response. This involves receptor activation and downstream signaling cascades that translate the external signal into changes inside the cell—altering enzyme activity, ion channel function, or gene expression. It’s about turning a chemical message in the synaptic cleft into a cellular response inside the neuron. Synthesis of neurotransmitters in vesicles is about producing the signal, not converting it into an intracellular response. Release into the synaptic cleft is the delivery of the signal, not the intracellular processing. Degradation by enzymes terminates or terminates the signal, not the intracellular signaling event.

Signal transduction is the process by which an extracellular chemical signal, such as a neurotransmitter, binds to a specific receptor on the target cell and is converted into an intracellular response. This involves receptor activation and downstream signaling cascades that translate the external signal into changes inside the cell—altering enzyme activity, ion channel function, or gene expression. It’s about turning a chemical message in the synaptic cleft into a cellular response inside the neuron.

Synthesis of neurotransmitters in vesicles is about producing the signal, not converting it into an intracellular response. Release into the synaptic cleft is the delivery of the signal, not the intracellular processing. Degradation by enzymes terminates or terminates the signal, not the intracellular signaling event.