1. By: Esther P., Namroo A., Kristin N.,
and Will C.

2.  Signal Pathways lead to the synthesis of
enzymes or proteins, not to activity.
 Three stages of responses:
 Signal Reception.
 Signal Transduction.
 Signal Response.
 (Page 213)

3.  Enzyme amplification signal.
 Each step gradually increase as steps get
higher.
 Amplification effect stems.
 The result of amplification.

5.  Each cell has variety of responses to a signal.
 Different Proteins.
 Cross paths.
 Different Receptors.

6.  These pathways used to be thought
independent, and linear ones.
 However, we now realize that things aren’t so
simple; therefore, we also now have a better
understanding of the processes of cellular
communication.
 (See figure 11.5)

7.  Scaffold proteins are crucial regulators of many key signaling
pathways.
 They interact or bind with multiple members of a signaling
pathway.
 They regulate signal transduction and help localize pathway
components to specific areas of the cell (ex. Plasma membrane,
cytoplasm, etc..)
 Example: Researchers are now finding scaffolding proteins that
permanently hold together networks of signaling-pathway
proteins at synapses.
 Why is this important?
 This “hardwiring”, per say, enhances the speed and accuracy of
signal transfer between cells.
 *RECALL that when a signal is relayed along a pathway, only
certain information is passed on.

8.  The time to remain alert is a short time.
 The there must be a reversibility to the changes
that signals produce.
 When signal molecules leave the receptor it
reverts to its inactive form.