the effects of neurotransmitters tend to be ________, whereas the effects of hormones tend to be ________.

The completed sentence is: “the effects of neurotransmitters tend to be fast and short‑lived , whereas the effects of hormones tend to be slower and longer‑lasting.”

In other words:

• Neurotransmitters: rapid onset, brief effects at very specific synapses in the nervous system.

• Hormones: slower to act, but their influence can persist for minutes to hours (or longer) and spread throughout the body via the bloodstream.

So the best fill‑in is: “faster; longer lasting.”