1. Cell Communication
Chapter 11
Study the diagrams!!

2. Communication Cell Junctions Cell-cell Recognition
Gap, Tight, Plasmodesmata
Cell-cell Recognition
Like the immune system!

3. Local – Paracrine (molecules like growth factors) and Synaptic (neurotransmitters)
Long Distance – Endocrine (hormones that travel in bloodstream)
Signaling

4. Signal Transduction Pathway

5. G- Protein Coupled Receptor
Some G-protein receptors are always on, some have to be turned on.
When G protein is bound to GDP, it is inactive

8. Animation that shows both G-protein and ion channels: Click here
The G-protein also works as a GTPase (breakdown of GTP into GDP and P)
Diseases- cholera, Botulism
Animation that shows both G-protein and ion channels: Click here

9. Tyrosine-Kinase Receptor

12. Animation: https://www.youtube.com/watch?v=kiHAdan2AOY
Used in processes where there are steps involved (mitosis), *several* responses at one time
Animation:

13. Ion Channel Receptor

16. z z
Amplification
Relay proteins amplify the signal, so we only need a little of the hormone
FIGURE

17. Phosphorylation Cascade

18. Second Messengers Non-protein Cyclic AMP (cAMP)
Adenylyl cyclase converts ATP into cAMP
Phosphodiesterase converts cAMP into AMP (so it shuts off the second messenger)
Animation: s/ /student_view0/chapter 17/animation__second_messenger_ _camp.html

19. Second Messengers (Con’t)
Ca2+
Higher concentration in ER and Mitochondria and outside the cell
Low concentration in cytosol
Calcium-ion pumps located in ER, Mitochondria, Cell Membrane
IP3 – inositol trisphosphate (second messenger)
PIP2 and DAG – don’t need to know

20. Growth Factors Don’t directly turn on genesz
Growth Factors
Don’t directly turn on genes
Turns on transcription factor to turn on a gene
DO NOT ENTER THE CELL

21. Intracellular Signalingz
Intracellular Signaling
Lipid-soluble hormones (steroids) can go into the cell because their receptor is in the cell!
Animation: om/sites/ /student _view0/chapter17/animation_ _intracellular_receptor_model .html

22. Cell Death (Apoptosis)
Death signal (morbid, I know) comes in
Cascade begins when Ced-4 and Ced-3 activate (you don’t need to know specifics)
Cell Death (Apoptosis)
Figure