According to studies, 80% of the data that we take in comes from our power of sight. Sight lets us take in 180° of images, perceive 1 million different colors, adjust what we see based on level of light & focus close up or miles away. Our vision is more detailed than any digital camera.
Organ system is the answer
A response from the amigdala. The reason for this is that when the medulla starts signalling brain regions that are in upper parts, especially the amigdala, this then triggers the fear response (amigdala is responsible for this) which in turn alerts us on a conscious level that we should leave this room for example and go to somewhere where more oxygen is present.
Answer:
Start from the bottom and go up.