Question

Write the steps in correct order to demontrate that $C{O}_2$ is produced during respiration.

Answer 1

The procedure of the experiment to demonstrate that CO₂ is released during respiration is as follows:

• Take some germinating gram seeds in a conical flask.
• Place a test tube containing KOH solution in the conical flask by hanging it.
• Seal the conical flask with a rubber cork.
• Insert one end of a U-shaped glass delivery tube in the conical flask through a hole in the rubber cork and the other end in a beaker containing water.
• Apply some Vaseline at the mouth of cork to make the conical flask air tight.
• Note the initial level of water in the beaker and leave the apparatus for an hour.

OBSERVATIONS:

• As the germinating seeds respire, carbon dioxide will be released. This carbon dioxide will be absorbed by KOH solution. As a result a vacuum will be created in the conical flask and this will create a suction pull that will pull the water from the beaker. Hence, water level win the beaker will decline.
• This shows that CO₂ is produced during respiration.