In chloroplasts, a) the light reactions take place in the thylakoid disks, whereas the dark reactions occur in the stroma b) the dark reactions take place in the thylakoid disks, whereas the light reactions occur in the stroma c) the light reactions take place in the thylakoid space, whereas the dark reactions occur in the stroma d) the dark reactions take place in the thylakoid space, whereas the light reactions occur in the stroma e) none of these

The correct answer is A) the light reactions take place in the thylakoid disks, whereas the dark reactions occur in the stroma.

Explanation:

Chloroplast is the double membrane organelle in the plant's cell which is responsible for the formation of organic material with the help of light and dark reaction.  

The light reaction takes place in the thylakoid disc where light energy is used to split water that feeds electron in the electron transport chain present in the thylakoid disc. These electrons are used to generate NADPH and ATP during the light reaction.

The NADPH and ATP produced during light reaction is used in the DARK reaction in calving cycle to produce carbohydrate(glucose). This process occurs in the stroma of the chloroplast and do not depend on light directly.

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