Oxidation of pyruvate occurs in mitochondria in pjotosthesizing cells as well. In such this occurs:
1. in photosynthetic cells in the light, while photosynthesis occurs concurrently
2. in non-photosynthesizing cells only
3.in photosynthesizing cells in dark periods and in other tissues all the time
4. in photosynthesizing cells in the light and in other tissues in the dark

For the synthesis of glucose, the source of hydrogen atoms is:

In cyclic photophosphorylation, the primary electron acceptor is:
1. An iron-sulfur protein
2. Plastocyanin
3. Plastoquinone
4. Water

If chloroplasts are illuminated with sunlight, the lowest pH would be observed in:

To establish a proton gradient across the thylakoid membrane, the protons are provided by:

Heme and iron-sulfur complexes in photosynthesis:
1. act as reducing agents
2. act as oxidizing agents
3. both oxidize and reduce during electron transport
4. are needed only in respiration but not in photosynthesis

Identify the correct statement:

The pathway shown in the figure will be seen in:

1. ${\mathrm{C}}_4$ plants
2. CAM plants
3. ${\mathrm{C}}_3$ plants
4. All photosynthetic plants

Carbon dioxide fixation will be inhibited by oxygen in:

1. cell I only.
2. cell II only.
3. neither cell I nor cell II.
4. both cell I and cell II.

Radioactive carbon [${}^{14}\mathrm{C}$] was fed to a plant during the day and after a short time was traced to oxaloacetate. The plant used in the experiment will be: