Researchers are investigating the effectiveness of various treatments on three individuals with a history of increased appetite. Individual I does not produce leptin but does have functional leptin receptors.
Individual II does produce leptin but does not have functional leptin receptors.
Individual III does not produce leptin and does not have functional leptin receptors.

Required:
Identify the way that leptin produced by fat cells of adipose tissue in the abdomen cansend a signal to the neuroendocrine cells in the hypothalamus.