Brief Answer:
2 different chemicals, slightly different effects,have some similarities

Detailed Answer:
HI, thanks for using healthcare magic

They are both neurotransmitters, this means that they are chemicals that are released/let out at the end of a nerve when an impulse/nerve transmission occurs in that nerve. The chemical then travels across a space between that nerve and goes to another nerve to stimulate it (cause it to work )

Dopamine is found in different areas of the body including the brain, blood vessels, kidneys and pancreas. In the brain, it travels along different pathways and has different functions .

In the brain, dopamine helps with :(1) motor function (movement)- this is the reason that persons with Parkinsons are given dopamine- there is a lack.
Some medications that are used in psychiatry reduce or affect dopamine's action and cause movement side effects

(2)it may also affect a person's motivation or arousal (this means being awoken or stimulated) or reinforcement.
It can play a role in reward stimulated behavior where pleasure from an activity or food or drink or action causes it to be repeated

SEROTONIN- this is actually mostly found in the gut (90%) of it. The remainder in the nervous system- brain and nerves throughout the body.
It helps regulate or control these things to some extent- mood, sleep and appetite.
The effect on mood is the reason that many anti depressants increase the level or effect of serotonin

It can also affect higher function such as memory and learning

I hope this helps, feel free to ask any other questions

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