2. Communication- signal pathways Distinguish among types of cell-to-cell communication List the four classes of membrane receptors. Explain how receptors facilitate specific cellular responses List and describe the components in specific 2nd messenger signal transduction pathways (see tables 6.1 and 6.2)

3. Autocrine Paracrine

4. Hormone Neurotransmitter

5. blood vessel epithelium muscle connective tissue The muscle around a blood vessel contracts & relaxes This is regulated by: autocrines, paracrines (H +, CO 2, etc) endocrines (ADH, ANP) neurotransmitters (NE,E)

6. Four classes of membrane receptors: There are also intracellular (non-membrane-bound) receptors that typically act as transcription regulators.

7. tyrosine kinase receptor/enzyme

8. G  G-protein coupled receptor

9. Two main classes of 7 Trans-membrane domain, G-protein coupled receptors (GPCR) 1.GPCRs that modulate adenylate cyclase, which converts ATP to cAMP, which activates protein kinase A. 2.GPCRs that activate PLC leading to hydrolysis of polyphosphoinositides (e.g. PIP2) generating the second messengers, diacylglycerol (DAG) & inositoltrisphosphate (IP3). DAG activates protein kinase C. IP3 releases intracellular calcium stores.

10. http://www.blackwellpublishing.com/matthews/neurotrans.html http://entochem.tamu.edu/Teaching/G-Protein/GProteinaudioMovie.html