Answer:
Dopamine
Step-by-step explanation:
Parkinson’s disease is a degenerative, progressive disorder that affects nerve cells in parts of the brain called the basal ganglia and the substantia nigra.
The neurotransmitter dopamine is produced by nerve cells in the substantia nigra and these nerve cells function in relaying information from the brain that plan and control body movement. In Parkinson's disease, the dopamine-producing nerve cells of the substantia nigra begin to die off . Symptoms such as tremor, impaired movement, stiffness, and balance problems occur when the loss of nerve cells is about 80%