Question

why are the plants that consume more than the usual 18 ATP to produce 1 molecule of glucose favoured in tropical regions ​

Answer 1

Answer:

           The C4 plants consume more than the usual 18 ATP, i.e., about 30 ATP, to produce 1 molecule of glucose and are favored in tropical regions. The C4 plants are uniquely adapted to grow better in hot and dry tropical regions because:

• The C4 plants have leaves that have a unique structure called the Kranz Anatomy with thick bundle sheath cells and dense mesophyll cells that aid in double carbon fixation.
• Unlike in other plants, where the carbon fixation takes place in chloroplasts by the action of Rubisco enzyme, the C4 plants fixate carbon in the cytoplasm activated by the enzyme phosphoenolpyruvate (PEP) carboxylase through the Hatch-Stack Pathway.
• Plants in a hot and dry climate cannot have their stomata open for long hours during day time so as to prevent dehydration. This PEP enzyme can fixate carbon even when the stomata are closed.