Chapter 3 summarizes the basic biology surrounding our psychology. Particularly i found the Endocrine System to be the most interesting because of how it can effect our emotions. More specifically the Pituitary Gland. The pituitary gland fascinates me because of it's many functions. This is why many people refer to it as the "Master Gland". This glands functions include everything from controlling blood pressure to our physical growth. There was a section in the chapter three that discussed a pituitary hormone called oxytocin that has been recorded to cause maternal and romantic love. It also has been known to influence how much we trust each other. In fact men exposed to nasal spray containing oxytocin were more likely to lend their team partners money in an investment game. If only we could all be exposed to a little more oxytocin.