From the brightness of the light of course. If the brightness is increasing it means the the light source is approaching and if the brightness is decreasing it means the light source is leaving.
The process which occurs in the structures that are labeled X is Kreb's cycle.
It has to do with releasing stored energy in the form of adenosine triphosphate (ATP). This is an extremely important part of metabolism and was first introduced by Hans Adolf Krebs in 1937.
Answer:
C. hormone molecules
Explanation:
hormones are secreted in glands and are transported to the organs where they affect it and cause changes.
