Bio1151b Chapter 11 Cell Communication
  1. Cell-to-cell communication is essential for                organisms. Animal cells communicate over short distances by            signaling and           signaling.
  2. Both plants and animals use           for long-distance signaling.
  3. Cell signaling comprises three stages:            ,               , and           .
  4. In reception, a         molecule binds to a           protein, causing it to change shape.
    • Signal molecules that are small or              , such as          hormones, can cross the plasma membrane and bind                receptors.
    • Other molecules transmit signals via plasma membrane receptors:            -linked receptors, receptor           kinases, and      channel receptors.
  5. In transduction, signals are relayed from receptors to         molecules, as in a cascade.
    • The energy molecule      is involved in steps where protein                  and dephosphorylation occur, often involving                 change in a protein.
    • Second messengers are small        -soluble molecules or ions, such as Cyclic AMP .
  6. Cellular response to a signal can include both              and          activity.
    • Multistep pathways may exhibit signal                , where each protein in the pathway activates           copies of the next component in the pathway.
    • Some responses involve turning genes on or off in the          .
  7. Each cell has a unique combination of           ,        , and           proteins, allowing wide              in their responses to different          .
    Review: Build a Signaling Pathway.