Question

Thirty corn seedlings of equal size were randomly assigned to one of three treatment groups. At the beginning of the experiment, the plants in group I were dried and the mass was determined. The plants in group II were maintained in light for a week. The plants in group III were maintained in the dark for a week. All conditions, other than light, were the same for groups II and III. At the end of the week, the plants in groups II and III were dried and the mass was determined.
To explain the increase in mass of the light-grown plants, identify ONE inorganic source of new plant mass and connect it to the cellular process underlying the increase in mass.

To explain the decrease in mass of the dark-grown plants, identify the overall chemical reaction that is occurring in the plant cells and connect it to the cellular process underlying the decrease in mass.

Answer 1

Answer:

See the answer below

Explanation:

To explain the increase in the mass of the light-grown plant, one inorganic source of new plant mass would be carbon from carbon dioxide. The carbon becomes fixed into the plant through a process known as photosynthesis. During this process, carbon dioxide combines with water in the presence of light to produce carbohydrates, a major component of plant mass. Oxygen is produced as a by-product. The process can be summarized by the following equation;

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

To explain the decrease in mass of the dark-grown plants, the loss of mass would be due to the breakdown of carbohydrates in the body of the plant through a process known as respiration. During this process, carbohydrate is broken down to release energy for the metabolism of the plant. Carbon dioxide and water are released as by-products and the entire process can be summarized by the equation below;

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