Question

1. Three groups of 100 identical radish seeds are germinated under different conditions. Group A is germinated with constant light and moisture, and produces tall straight seedlings with two green leaves. Group B is germinated with constant moisture in complete darkness, and produces long, floppy seedlings with two yellow leaves. Group C is germinated without light or moisture, and as a result the seeds never produce seedlings. When you measure the dry weights (all liquid water removed) at the end of the experiment, the results are:

Group A: 400 mg

Group B: 300 mg

Group C: 350 mg

The differences between groups are all statistically significant. Explain the weight changes in the three treatment groups.

Answer 1

Group A, this group seedlings started growing and producing food by the process of photosynthesis, when presented with light and moisture. Thus, they increased their mass.

Group B- produced no food, it formed seedling in the presence of darkness. It absorbed water and metabolised the stored food present in the seeds for formation of seedlings. As a result , the respiration rate of the seed and seedling increased for using up of energy and forming the structures and carry out metabolism. So, it lost carbon as lCO2., That is without any production. Thu, it lost more weight instead.

Group C- No change occured here, as nothing provided. The seed remains dormant. And no seedling formation due to absence of moisture and light. No loss or gain of material.