If the light is made unavailable than the biosynthetic phase of photosynthesis

Options

A. Will immediately stop.
B. Will stop after sometime .
C. Will stop after few hours .
D. Will have no effect and continue.

Answer

### Step-by-Step Solution:

1. **Understanding Photosynthesis**: Photosynthesis consists of two main phases: the light-dependent reactions and the light-independent reactions (also known as the biosynthetic phase or dark phase).

2. **Identifying the Biosynthetic Phase**: The biosynthetic phase does not directly require light. Instead, it relies on the products generated from the light-dependent reactions, specifically ATP (adenosine triphosphate) and NADPH (nicotinamide adenine dinucleotide phosphate).

3. **Role of ATP and NADPH**: ATP and NADPH produced during the light reactions are essential for the biosynthetic phase as they are used to fix carbon dioxide into organic molecules.

4. **Impact of Light Availability**: If light becomes unavailable, the biosynthetic phase will not stop immediately. It can continue for a certain period as long as there are sufficient ATP and NADPH available from previous light reactions.

5. **Duration of Continuation**: The biosynthetic phase will eventually cease when the stored ATP and NADPH are depleted. However, if light becomes available again, the biosynthetic phase can resume as the light-dependent reactions will produce more ATP and NADPH.

6. **Conclusion**: Therefore, the biosynthetic phase of photosynthesis will not stop immediately if light is made unavailable; it will continue for a while until the energy carriers (ATP and NADPH) are used up.