Our nervous system is specialized in many ways to help us maintain homeostasis, but there are a couple of major regions that take care of homeostasis for the most part. Your hypothalamus controls a large part of your primal involuntary actions, such as hunger and sleep. Your medulla oblongata controls breathing and heart rate. The Cerebellum controls balance and coordination, as well as involuntary muscle actions. However, all parts of tour brain interact to make sure and keep check that you are in homeostasis or will soon return to homeostasis.
Secondly, your brain uses feedback loops to control homeostasis. A negative loop will discourage behavior and bring you back to homeostasis, such as when you shiver and it's cold or sweat when it's hot. Positive feedback loops encourage a behavior to being you back to homeostasis, in which an example is childbirth, where a females body will produce more hormones to keep pushing until the baby is born and they are back in homeostasis.
Leucine and phenylalanine have hydrophobic side chains, which means that they can interact with valine in the pocket. All other aminoacids on the list have polar (two electrically charged) side chains and cannot form hydrophobic pockets.
