Photosynthesis Quiz

Describe Calvin cycle.

• The Calvin cycle is a process that occurs in the mitochondria of cells.
• The Calvin cycle is responsible for the breakdown of glucose into carbon dioxide.
• The Calvin cycle is a series of biochemical reactions in photosynthesis that convert carbon dioxide and other compounds into glucose.
• The Calvin cycle is a method of cellular respiration that generates ATP.

Explain photorespiration.

• Photorespiration is a wasteful pathway that occurs when RuBisCO fixes oxygen instead of carbon dioxide, leading to reduced photosynthetic efficiency.
• Photorespiration is a method of energy production that does not involve photosynthesis.
• Photorespiration is a beneficial process that occurs in all plants during the night.
• Photorespiration enhances photosynthetic efficiency by fixing more carbon dioxide.

Describe the anatomical structure of C4 leaf (Krantz anatomy) in comparison to C3 leaf.

• C4 leaves have a Krantz anatomy with mesophyll cells surrounding bundle sheath cells, while C3 leaves have a uniform mesophyll structure.
• C4 leaves lack specialized cells and have a simple leaf structure.
• C3 leaves contain bundle sheath cells surrounding mesophyll cells.
• C4 leaves have a uniform mesophyll structure like C3 leaves.

Explain carbon dioxide fixation in C4 plants and Crassulacean Acid Metabolism (CAM) plants.

• C4 plants utilize PEP carboxylase for initial CO2 fixation, while CAM plants fix CO2 at night and store it as malic acid.
• C4 plants fix CO2 during the day using ribulose bisphosphate carboxylase.
• C4 plants store CO2 as citric acid in the chloroplasts.
• CAM plants utilize PEP carboxylase for CO2 fixation during the day.

Differentiate the metabolism of C3, C4 and CAM plants.

• C3 plants store carbon as starch, C4 plants use the Calvin cycle at night, and CAM plants have no water conservation mechanism.
• C3 plants are found in arid regions, C4 plants are aquatic, and CAM plants are tropical trees.
• C3 plants use the Calvin cycle directly, C4 plants use a 4-carbon pathway for efficiency, and CAM plants fix carbon at night to conserve water.
• C3 plants have a higher photosynthetic rate than C4 plants, and CAM plants do not perform photosynthesis.

What is the process that occurs in the stroma and does not require light?

• Calvin cycle

• Light-dependent reactions

• Photorespiration

What is the first molecule to form from carbon fixation in C3 plants?

• 3-phosphoglycerate

• Glyceraldehyde-3-phosphate

• Ribulose bisphosphate

What is the major problem faced by C3 plants in hot and dry climates?

• Dehydration

• Overhydration

• Nutrient deficiency

What is the process where Rubisco fix oxygen instead of carbon dioxide in the presence of light?

• Photorespiration

• Calvin cycle

• Carbon fixation

What is formed when Rubisco incorporates oxygen to ribulose bisphosphate?

• 2-phosphoglycolate and 3-phosphoglycerate

• Glycerate-3-phosphate

• Glucose