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.
They divide the mass of the Earth by the volume, which gives the average density of the material in the earth as 3.2 ounces per cubic inch (5.5 g/cm3).. 5.5 g/cm3. The density of the Earth is higher than that of any other planet in our solar system. Sources vary when it comes to the density of the Earth. All the numbers that were provided are so close to each other, however, that they can each be considered valid.