Question

6. Seeds contain a lot of starch and oil to provide energy during germination and initial growth. Think about the change in biomass you expect to observe for seeds in the three different growth conditions. Based on your answers to previous questions (may be different from #1), predict for each growing condition in Table 2 the average biomass of the three replicates after 10 days (HINT: seeds have very little water, so each batch of seeds begins with -1.5g of dry biomass). Table 2. Predicted biomass changes for radish seeds in three growth conditions. Growth Condition Predicted Biomass at 10 days Observed Biomass (Check one per condition) Light, no water 0 <1.5 g 0-1.5 g 0 > 1.5 g Light, water 0 <1.5 g 0 -1.5g 0 > 1.5 g No light, water 0 < 1.5 g 0~1.5 g 0 > 1.5 g 000000

Answer 1

In the first condition, that is light with no water the biomass will go below 1.5g. This is because the light will dry out the seed but there will be no increase in biomass since germination and photosynthesis does not take place in the absence of water. So answer is <1.5g

In the second condition, that is in the presence of both light and water the seed undergoes photosynthesis since both the necessary elements are present and the biomass goes above 1.5. So the answer is >1.5g

In the third condition, that is in the presence of no light but sufficient water the seed germinates but will not grow further and undergo photosynthesis. So since there is no photosynthesis there is no increase and due to the presece of enough water there is no drying out of the seed. So the biomass will not undergo much change. So the answer is ~1.5g