Question

In an experiment some germinating seeds were placed in alarge air tight flask and left for 4 days.

a) suggest the expected changes in the composition of gases in the flask on the 5th day.
b) give a reason for your answer in (A) above.

Answer 1

The expected changes in gas composition in a flask with germinating seeds on the 5th day include a decrease in oxygen and an increase in carbon dioxide due to cellular respiration, which occurs in the absence of light, leading to the consumption of oxygen and production of carbon dioxide.

Step-by-step explanation:

Changes in Gas Composition in a Flask with Germinating Seeds

When germinating seeds are placed in an airtight flask and left for several days, one could expect a change in the composition of gases in the flask by the 5th day. The concentration of oxygen (O2) in the flask is likely to decrease, while the concentration of carbon dioxide (CO2) is expected to increase. This is due to the process of respiration that the seeds undergo during germination, using oxygen to release energy from their stored nutrients, and producing carbon dioxide as a by-product.

The reason for this change is that, unlike photosynthesis, which can only occur in the presence of light, respiration occurs all the time inside the cells of the seeds. Since the flask is sealed and presumably kept in darkness, or at least without adequate light for photosynthesis, the seeds would not be able to produce new oxygen through photosynthesis but will continue to consume oxygen for respiration.