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Cell communication

AP.BIO: IST‑3 (EU), IST‑3.A (LO), IST‑3.A.1 (EK), IST‑3.B (LO), IST‑3.B.1 (EK)


Image credit: Adapted from CNX OpenStax [CC BY 4.0], via Wikimedia Commons
Which of the following best describes the cell communication occurring in the figure above?
Choose 1 answer: