Page 24 - E-Biology Sec.2 2024-2025 U1_Handy

2)Dark (Enzymatic) reactions (Sensitive to temperature)

They occur in the chloroplast inside the stroma (matrix).
They occur in light / darkness and the temperature if the limiting factor.

Fixation of carbon dioxide by its combining + hydrogen on NADPH2 and the
energy stored in ATP then formation of carbohydrates.
So, ATP & NADPH2 (Energy-fixing compounds).

Melvin Calvin Experiment

Chlorella
Hot

Results: After 2 seconds from exposing to the light:

The 1st stable.

1- 3C atoms compound was formed which is phosphoglyceraldehyde PGAL

It is a high-energy compound which is used in the cellular respiration.

It is used in building glucose, starch, proteins & fats.

2- Hexose sugar (glucose) isn’t formed in 1 step,
but through several intermediate reactions
which are catalyzed by enzymes.

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First Term