Differentesis And Light Synthesis: The Process Of Photosynthesis

Introduction

Photosynthesis is the process of converts light energy into chemical energy. Photosynthesis have nourish directly or indirectly the entire of the world living things. Photosynthesis only will occur in plants, algae, certain other protists and some prokaryotes. Inside the plant cell, there is an organelle responsible to make food as sugar and carry out respiration; the functional organelle is chloroplast. The chloroplasts are found mainly in cells of the mesophyll, which is the interior tissue leaf. Generally, the photosynthesis can be summarised as follow:

6CO2 + 12H2O  C6H12O6 + 6O2 + 6H2O

Photosynthesis consists of the light reaction and Calvin cycle (dark reaction). In the light reaction, which occur in the thylakoid, water will be split, oxygen will be released, NADP + will been reduced to NADPH (electron carrier) and ATP will been generated from ADP by photophosphorylation. In addition, for Calvin cycle, which in the stroma, it will form sugar from carbon dioxide by using ATP and NADPH as energy (Jane,et al., 2010).

An isolated chloroplasts that can evolve oxygen in the absence of CO2 was shown by a scientist who namely Robert Hill in 1937. In this experiment, the Hill Reaction has showed an important phase of light reaction. With the presence of light and chloroplasts, the

Once the artificial electron acceptor had been reduced, it will change its colour. In this experiment, the artificial electron acceptor been chosen is DCPIP. It showed blue colour when it is in oxidized form while it’s reduced form show colourless. In this experiment, 620 nm of absorbance will be used to measure the rate of the Hill reaction (Westfield States University, n.d.).