By: Esther P., Namroo A., Kristin N., and Will C.
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)
Enzyme amplification signal. Each step gradually increase as steps get higher. Amplification effect stems. The result of amplification.
Each cell has variety of responses to a signal. Different Proteins. Cross paths. Different Receptors.
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)
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.
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.