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Chlorophyll, Chloroplasts, Light Reaction and Dark Reaction

In my 1st web blog I discussed how one can make photosynthesis, an easy learning experience. Most of you might be knowing everything about photosynthesis but this process has been my fascination since my school days. 
Let's dive little dip in the process. Today we will learn about chlorophyll, chloroplasts, light-dependent reactions, and dark reactions.

Chlorophyll, light reactions.
The figure: 1.1 above is the section of chloroplast, showing 1).Thylakoid, 2).Thylakoid lumen, 3).Granum, 4).Stroma, 5).Outer membrane, 6).Inner membrane.

No.1 Chlorophyll:

Almost all plants we see around are green in color, is due to the green pigment called chlorophyll, found in plants. In the chloroplasts, chlorophyll is located in the membrane of thylakoids.(refer fig:1.1)
Further, Chlorophyll has the unique charachteristic or capability of absorbing sunlight, which in turn helps plants manufacture their own food in the form glucose and other organic molecules.

No.2 Chloroplasts:

Chloroplasts are found in the green tissues of plants and algae. It is also found in the non green photosynthetic tissues, such as brown blades of brown alga and plants with red leaves.
(refer fig:1.1)

The process of photosynthesis consists of two main reactions as follows:

Photosynthesis
 The figure: 1.2 above shows thylakoid membrane where light-dependent reactions takes place.

1.Light-dependent reaction:

Light-dependent reaction
Figure:1.3

As the name suggests direct or indirect presence of sunlight is inevitable for this reaction to occur. In the presence of sunlight "chlorophyll(p680)", in the plants gets oxidized to "p680+" and free electrons are released.(refer fig:1.3)
This free electrons are used by ATP+NADP; And side by side this oxidized "chlorophyll(p680+)" further oxidizes H2O to form oxygen.(refer fig:1.3)
Light-dependent reaction occurs in the thylakoid membranes.(refer fig:1.2)

2.Dark reaction:

As the name suggests this reaction do not require any light. Energy from ATP+NADP is used to fix carbon dioxide and glucose and other organic molecules are formed in the end.
Dark reaction occurs outside thylakoids in the Stroma.
Note:- It's true that dark reactions are not independent of light but it can occur in both absence as well as presence of light.

I hope you liked this blog. I would love to hear from you. 
Your every feedback would inspire me to give you better scientific content each time.

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