Page 1 - HA 3

SAI International School
Std -X, Subject- Biology
Chapter- Life Processes
Subtopic-Respiration I
Module-6
Home Assignment III (Experiment &Activities)

Experiment-2
Aim of the experiment: To study that CO 2 is given out during respiration in
germinating seeds

Materials Required-

Moist germinating seeds, conical flask, freshly prepared KOH, delivery tube, beaker
containing water.

Procedure
Take moist germinating seeds in a conical flask.

Take some freshly prepared KOH in a small test tube and hang it inside the flask.

Fit a delivery tube through a cork fitted into the conical flask.

The other end of the delivery tube should dip in a beaker containing water.

The experimental set up should be kept for 3-4 hrs without disturbing.

Observaion:
After some time, the level of water in U-shaped delivery tube, dipped in water of the
beaker, rises.

Inference: Germinated gram seeds in a conical flask release CO 2 during respiration.
The CO 2 released is absorbed by KOH present in the hanging test tube in the
conical flask. This creates a vacuum in conical flask which causes upward
movement of water in the delivery tube leading to change in level of water in the
delivery tube.

EXPERIMENT NO.2-Lab Worksheet