[Campbell Biology P.1049] A researcher observes that certain cells secrete a signaling molecu... | Practice Question

A researcher observes that certain cells secrete a signaling molecule that then binds to receptors on neighboring cells, initiating a response. However, if these same cells secrete a different molecule that binds to their own receptors, a self-regulatory process is activated. What types of signaling are observed, respectively?

  • A: Endocrine and synaptic.
  • B: Paracrine and autocrine.
  • C: Autocrine and paracrine.
  • D: Neuroendocrine and endocrine.

Explanation

The text states that paracrine signaling involves local regulators acting over short distances to affect neighboring cells, while autocrine signaling involves molecules that bind to their own receptors i.e., affect the cells that secrete them . The scenario directly aligns with these definitions.