Question

DRY MASS OF CORN SEEDLINGS GROWN UNDER DIFFERENT CONDITIONS

Answer 1

Answer:

See the answer below

Explanation:

(a) One of the inorganic sources of new plant mass for the light-grown plants is the atmosphere. The carbon in the form of carbon dioxide in the atmosphere is sequestrated into the body of the light-grown plants through a process known as photosynthesis. During this process, the inorganic carbon dioxide becomes fixed into the body of the plant through a series of steps that include both light-dependent and light-independent. The overall equation of the process is as below:

$6CO_2 + 6H_2O + Light --> C_6H_1_2O_6 + 6O_2$

As more plant mass is being gained by photosynthesis, some of the gained mass is also being lost to energy generation through a process known as respiration. Respiration is like the complete opposite of photosynthesis but a gain in mass is still possible because the rate of photosynthesis is more than the rate of respiration in the light-grown plants.

(b) The chemical reaction that can be held responsible for the decrease in mass of the dark-grown plants is respiration. Some of the mass is lost to energy generation and this mass cannot be recouped by adequate photosynthesis due to light limitation. The energy is needed to metabolic processes that would keep the plants alive. The equation of respiration is as below:

$C_6H_1_2O_6 + 6O_2 --> 6CO_2 + 6H_2O + Energy$