In this session, we cover cell signaling, or how cells “talk” (sending, target, non-target cell). We cover the 3 main types of signaling (direct contact, local signaling, long distance signaling). We provide 3 types of examples of long distance signaling (yeast cells [have “genders"], quorum bacteria, and antigen recognition by T cells). We cover the 3 stages of signal transduction and explain the signal phosphorylation. We show how signals are amplified and use a multiple choice question to show how if you can read a graph and be good critical thinker, you can answer the question.