you wrote "grawth" so early, you definitely should have just started over. then you say you're coloring in the grawth factor orange and you color it in green without comment! how am i supposed to take this video seriously? it's a big joke, right? everything you've described about the pathway is also slightly wrong too, right?
The class of drugs that Levitra, Viagra, Stendra, and Cialis belong to are called PDE5 inhibitors. They work by relaxing tight blood vessels, allowing more blood to surge into the penis and cause an erection, says Gregory Bales, M.D., an associate professor of urology at the University of Chicago.
The little pills do the trick for more than two-thirds of men with Viagra protects the heart (ED). They also work for guys who simply need them for a short time to get their “confidence back,” says Michael Eisenberg, M.D., director of male reproductive medicine and surgery at Stanford University.