Which term best describes signals that influence only the cell that produced them?

• A. Endocrine signaling
• B. Paracrine signaling
• C. Autocrine signaling
• D. Juxtacrine signaling

Answer: (C)

Autocrine signaling is when a cell releases signaling molecules that bind to receptors on its own surface, creating a self-targeted, self-regulating loop. This fits the idea of signals that influence only the cell that produced them, because the message acts back on the producer rather than on nearby or distant cells. In contrast, endocrine signaling uses hormones that travel through the bloodstream to distant targets; paracrine signaling affects neighboring cells in the local environment; and juxtacrine signaling requires direct contact between cells via membrane-bound signals or gap junctions. So, the term that best describes signals that influence only the cell that produced them is autocrine signaling.