The Calvin Cycle reactions have been called the Dark Reactio

The Calvin Cycle reactions have been called the Dark Reactions. Why is this description misleading? Choose the ONE BEST answer.

Question 4 options:

Because when the sun goes down it is not totally dark, sometimes the moon is shining.

The term Dark Reactions is not misleading, the reactions do only work in the dark.

Because the amount of ATP and NADH is too low during the night to support Calvin Cycle reactions.

Because the Calvin Cycle is not active during the night owing to both limiting amounts of ATP+NADPH and inactive enzymes.

Because the Calvin Cycle enzymes are not active in the dark.

Rubisco enzyme activity is regulated by pH and magnesium ion.

Because the amount of ATP and NADPH needed for carbon fixation is limiting and there is not enough available during the day to run the Calvin Cycle.

Because the reactions work under all conditions during a 24 hour cycle, so it is misleading to say they only work at night.

Solution

Because the Calvin Cycle is not active during the night owing to both limiting amounts of ATP+NADPH and inactive enzymes.

Calvin Cycle is not totally independent of light since it relies on ATP and NADH, which are both products of light-dependent reactions. Also the Calvin Cycle enzymes are activated in the presence of light. Hence Calvin Cycle canot be entirely called as dark reaction as it is functional on light dependent sources of energy ATP, NADPH, and the activity of its enzymes is also light dependent.