DENDROLOGY

Detailed explanation-1: -In C4 photosynthesis, where a four-carbon compound is produced, unique leaf anatomy allows carbon dioxide to concentrate in ‘bundle sheath’ cells around Rubisco. This structure delivers carbon dioxide straight to Rubisco, effectively removing its contact with oxygen and the need for photorespiration.

Detailed explanation-2: -In photosynthetic tissues, PEPC participates in the exchange of CO2 and water between a leaf and the atmosphere through its role in guard cell metabolism. Additionally, in C4 species PEPC catalyzes the first carboxylation reaction of C4 photosynthesis in the mesophyll cells (Kanai and Edwards, 1999).

Detailed explanation-3: -A unique leaf anatomy and biochemistry enables C4 plants to bind carbon dioxide when it enters the leaf and produces a 4-carbon compound that transfers and concentrates carbon dioxide in specific cells around the Rubisco enzyme, significantly improving the plant’s photosynthetic and water use efficiency.

Detailed explanation-4: -Under high temperature, high light, and the current CO2 concentration in the atmosphere, the C4 pathway is more efficient than C3 photosynthesis because it increases the CO2 concentration around the major CO2 fixating enzyme Rubisco.

Detailed explanation-5: -Due to their reduced rate of photorespiration and high rate of photosynthesis, C4 plants are more efficient than C3 plants. The main enzyme of carbon fixation in the Calvin cycle is RuBisCO. It shows an affinity for both CO2 and O2.