The signal will start from the eyes. The message is carried by sensory neurons to the spinal cord. There, the "impulse" will transfer to motor neurons which will carry it to the brain. So in short:
Sensory neurons --> spinal cord --> motor neurons --> brain
Answer: IT CAUSES PATHOGENS TO STICK TOGETHER
Explanation:
An unprotected traveler's blood would boil at normal body temperatures because the pressure is so low. Temperatures in the mesophere decreases with altitude, because there are few gas molecules in the mesophere to absorb the sun's radiation, the heat source is the stratosphere below. The air in the mesophere has extremely low density and as a result the air pressure is very low.
