Which statement best contrasts endocrine and nervous signaling?

Which statement best contrasts endocrine and nervous signaling?

• A. Endocrine uses electrical impulses, nervous uses hormones
• B. Endocrine: hormones, slow, long-term, widespread; Nervous: nerve signals, quick, short-term, localized
• C. Endocrine responses are instantaneous and localized
• D. Nervous system uses hormones for broad, long-term effects

Answer: (B)

Endocrine and nervous signaling differ in speed, duration, and scope. Endocrine signaling uses hormones released into the bloodstream, so the effects take longer to start but last longer and can affect many tissues throughout the body. Nervous signaling uses electrical impulses along neurons to synapses, producing rapid responses that are usually quick and highly localized to specific targets. This makes the statement describing hormones with slow, long-term, widespread actions for the endocrine system, and nerve signals with quick, short-term, localized actions for the nervous system the best match. For example, adrenaline released into the blood can prepare multiple organs for action over minutes to hours, whereas a reflex like moving a hand away from a hot surface happens in milliseconds at a specific synapse. Other options misstate how signaling works: electrical impulses are the hallmark of neural signaling, not endocrine; nervous signaling isn’t defined by hormonal broad effects; and endocrine responses aren’t instantaneous or confined to a single localized area.

Endocrine and nervous signaling differ in speed, duration, and scope. Endocrine signaling uses hormones released into the bloodstream, so the effects take longer to start but last longer and can affect many tissues throughout the body. Nervous signaling uses electrical impulses along neurons to synapses, producing rapid responses that are usually quick and highly localized to specific targets.

This makes the statement describing hormones with slow, long-term, widespread actions for the endocrine system, and nerve signals with quick, short-term, localized actions for the nervous system the best match. For example, adrenaline released into the blood can prepare multiple organs for action over minutes to hours, whereas a reflex like moving a hand away from a hot surface happens in milliseconds at a specific synapse.

Other options misstate how signaling works: electrical impulses are the hallmark of neural signaling, not endocrine; nervous signaling isn’t defined by hormonal broad effects; and endocrine responses aren’t instantaneous or confined to a single localized area.