The bottom driver is like the suspension for the sled, resulting in a smoother travel. And yes, the handles for the bottom athlete are significant too. The top man who sees the track signals the man in bottom (mostly using head movement) to help steer.
The two reactions which occur during photosynthesis are light  reaction and dark reaction. Light reaction takes place only in the  presence of light. Dark reaction can occur â¦ with or without light. 1 person found this useful.
Light Reactions. The first of two major stages in photosynthesis (preceding the Calvin cycle). These reactions, which occur on the thylakoid membranes of the chloroplast or on membranes of certain prokaryotes, convert solar energy to the chemical energy of ATP and NADPH, releasing oxygen in the process.