A Shortage of Dopamine. Parkinson's disease occurs when nerve cells, or neurons, in an area of the brain that controls movement become impaired and/or die. Normally, these neurons produce an important brain chemical known as dopamine, but when the neurons die or become impaired, they produce less dopamine.arkinson's disease occurs when nerve cells, or neurons, in an area of the brain that controls movement become impaired and/or die. Normally, these neurons produce an important brain chemical known as dopamine, but when the neurons die or become impaired, they produce less dopamine.
Weight density is not a term. Weight is the effect of gravity on a Mass and will be less on the Moon since the moon has less mass and therefore less gravity than the Earth.Density is mass/volume and since mass is constant, density would also be constant.aking the world better, one answer at a time. Weight density is not a term. Weight is the effect of gravity on a Mass and will be less on the Moon since the moon has less mass and therefore less gravity than the Earth. Density is mass/volume and since mass is constant, density would also be constant.
An object on the Moon would weigh less than it does on Earth because of the lower gravity, but it would still have the same mass. This is because weight is a force, while mass is the property that (along with gravity) determines the strength of this force.