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.
4.
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.
