Caffeine will block the action of phosphodiesterase and thus the enzyme will not be activated to break down cAMP. Caffeine has some effects which are psychological in nature. At the cellular level, caffeine blocks the action of phosphodiesteerase. Phosphodiesterase is the one that break down the cAMP inside the cell.
Answer:An increase in light intensity causes both pupils to contract (see iris) even if only one retina is directly stimulated. This is known as a consensual reflex. Conversely, a decrease in light intensity causes dilation of the pupils
The species is on CITES Appendix II, but its status is poorly known. The IUCN Red-List (2007, www.iucnredlist.org) classified it as Lower Risk/Least Concern