In recent molecular genetic studies, genes associated with the neurotransmitter Dopamine have been linked to ADHD.
ADHD stands for Attention Deficit Hyperactivity Disorder. People with ADHD have a hard time focusing on tasks. Scientists have found that the low levels of dopamine in the brain are associated with the symptoms of ADHD. It is because the neurons in the brain have a high amount of protein called the dopamine transporters. These proteins block the dopamine from passing between the neurons. This decreases the effect of dopamine.
Cerebellar injury results in movements that are slow and uncoordinated. Individuals with cerebellar lesions tend to sway and stagger when walking. Hope this helps! ;D
A signal cascade is a series of chemical reactions which are triggered by a stimulus acting on a receptor that is then transduced to the intracellular space through second messengers. Finally, effector molecules receive the signal causing a cellular reaction to the initial stimulus. A signal cascade is very useful because it facilitates and accelerates the communication between cells that could be in different parts of a living organism. This communication is vital for cell processes in complex multicellular organisms.