A fixed/set mass of germinating seed is added to the respirometer.
A control tube is also set up containing glass beads of same mass.
The respirometer is kept into a thermostatically water bath at 16°C.
The apparatus is made airtight by placing a bung at the opening with two
tubing’s which are both closed off. One of them is closed with clip and
the other has coloured liquid inside along a scale.
The clip is opened, and air is allowed to enter. The apparatus is left for
10 mins.
During this time there will be a decrease in the volume of air in the test
tube due to oxygen consumption by the germinating seed. And all co2
will be absorbed by the absorbent.
The decrease in volume of the air will reduce the pressure in the tube
and cause the coloured liquid to move towards the test tube.
Test 1 is volume of oxygen take up can be measured by multiplying the
distance moved by the coloured liquid and area of the glass tubing (in a
set amount of time) and area of the glass tubing (in a set amount of
time)me of oxygen take up can be measured by multiplying the distance
moved by the coloured liquid and area of the glass tubing (in 10 mins)
Test 2 is The experiment is repeated using glass beads, so the distance
moved by coloured liquid is a result of both Oxygen and carbon dioxide
released.
The volume of Co2 released is the Difference between test 1 and test 2.
The experiment is repeated thrice, and mean value is taken.
The RQ can be calculated by