I think this is a poorly worded question andthe answers are poor too. Why?
If plants are grown for several days in "how much 14CO2" in place of "how much 12CO2" doesn't tell us the conditions initially.
The answers are not much better. "A large/small increase/decrease" doesn't tell us much. How much is large and how much is small. However, in view of all of this, I think your answer probably is the one your prof wants.
If plants are grown for several days in an atmosphere containing 14CO2 in place of 12CO2, one would expect to find:
very little radioactivity in the growing leaves
large amounts of radioactive water released from the stomates
a large increase in 14C in the starch stored in the roots - Correct!!!
a large decrease in the rate of carbon fixation in the guard cells
an increase in the activity of RuBP carboxylase in the photosynthetic cells
Can someone explain why this answer (#3) is correct?
1 answer
1 answer