Question

give a reason for your observation.the seeds are seen on the top of the mercury​

Answer 1

The germinating seeds respire in a situation when these are completely cut off from air in the presence of a continuous column of mercury. The carbon dioxide gas released gets collected at the top of the tube and displaces mercury. The CO2 released disolves in KOH and the mercury level rises again.

I hope you understand.

Answer 2

Explanation:

the germinating seeds respire in a situation when these are completely cut off from air in the presence of a continuous column of mercury.the carbon-dioxide gas released gets collected at the top of the tube and displaces mercury.the Co2 released disolves in kOH and mercury level raises again