The C4 pathway ____.
A) produces large amounts of carbohydrates
B) is less efficient than the C3 pathway
C) is the mechanism of photorespiration
D) involves the activity of rubisco
E) fixes carbon twice

Question

The C4 pathway ____.  
A) produces large amounts of carbohydrates
B) is less efficient than the C3 pathway
C) is the mechanism of photorespiration
D) involves the activity of rubisco
E) fixes carbon twice

Quizplus · Accepted Answer

The C4 pathway involves fixing carbon twice, first in mesophyll cells and then in bundle sheath cells, which allows for more efficient CO2 uptake in hot and dry conditions. It is a mechanism to reduce photorespiration and increase efficiency in carbon fixation. It does not produce more carbohydrates than the C3 pathway and is more efficient than the C3 pathway in certain conditions. Rubisco activity is present in both pathways.

The C4 Pathway ____