The atmosphere is quite dusty, giving the Martian sky a light brown or orange-red color when seen from the surface; data from the Mars Exploration Rovers indicate that suspended dust particles of roughly 1.5 micrometres diameter.
Glutamate is a powerful excitatory neurotransmitter that is released by nerve cells in the brain. It is responsible for sending signals between nerve cells, and under normal conditions it plays an important role in learning and memory.
Glutamate flow in the brain is normally kept in check by a system of dam-like structures, which release a trickle of the substance only when and where it is needed. But burst a damâas happens in stroke, head trauma, and some other neurological disordersâand the treacherous messenger floods the brain.ead injury or stroke can cause a surge in glutamate, leaving damaged neurons in its wake. But a new method may help keep the chemical messenger in check. When a stroke or head injury releases a flood of the chemical messenger glutamate, the excess glutamate leaves damaged neurons in its wake.