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.
Needs of living things. Soils. Light and dark reactions in photosynthesis. Photosynthesis is divided in two parts: 1. Light-dependent reactions (light reactions). 2. Light-independent reactions (dark reactions). Light reactions need light to produce organic energy molecules (ATP and NADPH).