What are the chemical imbalances that lead to depression, anger and happiness and sadness.. please illustrate with diagrams and mention the...

I'm sorry to say that there is not a lot of good science
to support the idea that these conditions are caused by chemical imbalances. Anger,
happiness, and sadness have not been studied because they are accepted as normal and
reasonable human emotions; however, depression has been extensively studied and given
disease status.

The common concept that low levels of
serotonin in the brain cause depression has its roots in the 1960's. At that time it was
discovered that depressed people had measurably lower levels of serotonin than
non-depressed people, and pharmaceutical companies promptly developed and began to
market SSRI's, or Selective Serotonin Reuptake Inhibitors, such as Prozac. These drugs
are designed to increase the level of the neurotransmitter serotonin in the patient's
brain.

The problem is that we have a chicken-or-the-egg
problem here. More recent research indicates that depression, which has a number of
physical effects, creates the lowered serotonin levels, and not the other way around.
However the pharmaceutical companies are in the business of selling drugs, and they have
worked hard to convince both the public and the medical community that depression is
simply a chemical imbalance, and is easily treatable with
drugs.

The first link below will take you to a pdf of an
excellent scientific review of the literature on this topic.