.Structure of Chloroplast.

Chloroplasts are important cell organelle present in plant cells to carry out photosynthesis. These are discovered by Julius Von Sach. 
The chloroplast is a three layered membranous structure. The outer two layers form it's outer covering whereas the third layer is folded in the stacks like structure called 'grana'. These membranous stacks are called thyllakoid membrane. It is a site for capturing solar energy. The intermediary fluid found in the third layer is called 'stroma' which is a site for all enzymatic reactions during photosynthesis. 
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The chlorophyll is a green color pigment present inside the chloroplasts. It was first isolated by Pelletier and Caventou. It contains one atom of magnesium. It's structure is similar to that of  'heam ' of haemoglobin. The two major kinds of chlorophyll are 'chlorophyll-a' which is blue green in color and 'chlorophyll- b' which is yellow green in color. Around 250 to 400 such pigments are grouped together to form light harvesting complex. These are the photosynthetic units of chloroplasts. 

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