1. Chemical Signals 1 BIOL 1407

2. Chemical Signals Cells use chemicals to communicate with other cells http://www.livevideo.com/video/9DF33CE7 B1014B55BEF2322395D72133/neutrophil -chemotaxis.aspxhttp://www.livevideo.com/video/9DF33CE7 B1014B55BEF2322395D72133/neutrophil -chemotaxis.aspx Photo Credit of Neutrophil engulfing anthrax bacteria: Tim Vickers, 2007, Wikimedia Commons

3. Chemical Signaling: Direct Contact

4. Chemical Signaling: Short-Distance

5. Chemical Signaling: Long- Distance

6. Chemical Signaling Between Individuals Pheromones Video of Orchid Wasp Mimic: http://www.youtube.com/w atch?v=-h8I3cqpgnA http://www.youtube.com/w atch?v=-h8I3cqpgnA Photo credit for Spined Soldier Bug eating Mexican Bean Beetle larvae: USDA, 2006, Wikimedia Commons Article on Spined Soldier Bug and his pheromones: http://www.nytimes.com/1992/03/01/new s/cuttings-the-enemy-s-enemy-is-the- soldier- bug.html?partner=rssnyt&emc=rss&pag ewanted=all http://www.nytimes.com/1992/03/01/new s/cuttings-the-enemy-s-enemy-is-the- soldier- bug.html?partner=rssnyt&emc=rss&pag ewanted=all

7. Signal Transduction Pathways

8. Receptors

9. Target Cells: Have Receptors for Signal

10. Target Cells and Specificity

11. Types of Hormones

12. Transport and Receptor Location

13. Water- Soluble Hormones

14. G Proteins

15. Second Messengers cAMP cGMP IP 3 and DAG Calcium Calmodulin

18. Lipid- Soluble Hormones

19. Steroid Hormones Brassinosteroids in plants Steroid hormones in animals –Synthesized from Cholesterol –Testosterone, Progesterone, Estrogens –Cortisol and Aldosterone from adrenal cortex

21. Seed Dormancy and Germination ABA –High levels inhibit germination = promotes dormancy Gibberellins –High levels promote seed germination

22. Al-your-ownskew-Tell-um

23. Trigger for Desert Seed Germination: Rain Photo Credit for Storm Over Western Ghats: PlaneMad, 2006, Wikimedia Commons

24. Desert Seed Germination Attenborough Video: –http://www.you tube.com/watc h?v=z1IBnHIO Fxshttp://www.you tube.com/watc h?v=z1IBnHIO Fxs –Photo Credit for South Africa Desert in Bloom: Winfried Bruenicen, 2001, Wikimedia Commons

25. Volatile Chemicals Jasmonic Acid and Plant Volatiles Dodder plant seeks close relationship with tomato plant –http://imagearchive.ps u.edu/displayimage.ph p?pos=-19895http://imagearchive.ps u.edu/displayimage.ph p?pos=-19895 Photo Credit for Dodder in Bloom: Michael Becker, 2005, Wikimedia Commons

26. Photo Credit for Dodder on Acacia: Khalid Mahmood, 2007, Wikimedia Commons

28. Photo Credit for Parasitoid Wasp on Plant Bug Nymph: Scott Bauer, USDA, 2003, Wikimedia Commons

29. The End Unless otherwise specified, all images in this presentation came from: Campbell, et al. 2008. Biology, 8 th ed. Pearson Benjamin Cummings.