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PHOTOSYNTHESIS
Photosynthesis (Figure 15) is the process of converting light energy
to chemical energy stored in the bonds of sugar. A process driven by light
energy where glucose molecules (or other sugars) are constructed from
water and carbon dioxide, and oxygen is released as a by-product. It occurs
in the chloroplast (Figure 17).
light
6 CO2 + 6 H2O C6H12O6 + 6 O2
chlorophyll
Figure 15. Photosynthesis
Photosynthesis occurs in two stages. In the first stage, light-
dependent reactions or light reactions (Photo II and Photo I) capture the
energy of light and convert it into chemical energy through formation of 2
compounds: ATP (energy storage molecule) & NADPH (electron carrier).
Also, water molecules are converted to oxygen gas. During the second
stage, the light-independent reactions or dark reactions (CO2 fixation or
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