Indirect signal transduction involves which of the following?

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Multiple Choice

Indirect signal transduction involves which of the following?

Indirect signal transduction relies on a cytoplasmic second messenger to relay and amplify the signal from a cell-surface receptor to intracellular effector proteins. When a ligand binds its receptor, the receptor activates a cascade that generates small, diffusible molecules such as cyclic AMP, IP3, DAG, or calcium. These second messengers then diffuse within the cytoplasm and activate target proteins like kinases or ion channels, producing a coordinated cellular response. This setup explains why a single receptor–ligand event can produce a large, amplified response, since each receptor can generate many molecules of second messenger that interact with multiple targets. The other ideas don’t fit because signaling directly via the receptor without intermediates describes direct transduction, second messengers are not exclusive to prokaryotes, and signaling via second messengers is precisely characterized by amplification of the signal.

Indirect signal transduction relies on a cytoplasmic second messenger to relay and amplify the signal from a cell-surface receptor to intracellular effector proteins. When a ligand binds its receptor, the receptor activates a cascade that generates small, diffusible molecules such as cyclic AMP, IP3, DAG, or calcium. These second messengers then diffuse within the cytoplasm and activate target proteins like kinases or ion channels, producing a coordinated cellular response. This setup explains why a single receptor–ligand event can produce a large, amplified response, since each receptor can generate many molecules of second messenger that interact with multiple targets.

The other ideas don’t fit because signaling directly via the receptor without intermediates describes direct transduction, second messengers are not exclusive to prokaryotes, and signaling via second messengers is precisely characterized by amplification of the signal.

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