I hate poachers and I love animals, but this guy I hard not to love and he does make a good villain. Utterly cruel and psychotic, he loves killing and is greedy. In fact, he's so psychotic that he attempts to feed Cody to the crocodiles when he no longer has use for him.
The first is leptin, which is a hormone secreted by your fat cells that acts as an appetite suppressant. Leptin levels peak when you fill up on food. So, when you eat a lot, your appetite goes away. If you ever said, 'I am so full I couldn't eat another bite,' then in that moment, your body was flooded with leptin.
Cholecystokinin, previously called pancreozymin, is synthesized and secreted by enteroendocrine cells in the duodenum, the first segment of the small intestine. Its presence causes the release of digestive enzymes and bile from the pancreas and gallbladder, respectively, and also acts as a hunger suppressant.