Hormones play a profoundly critical role in the administration of behaviour, and physiology of humans--for example: the control of growth. These signaling molecules cause changes in the human body through a delicate, and complex system—the nervous system. One of those molecules that has caught the attention of many biologists is Leptin. Leptin is a hormone (signaling molecule) that has profound effects on a mammal’s food intake, energy balance and physiology with respect to the nervous system. Every mammal needs energy to help it perform important biological processes. That energy comes from food. Taking this fact in to consideration a question arises--how does an organism know that it requires energy? The answer is Leptin. When
