- Two un-branched plants
- Adhesive tape
- Two boiling tubes marked as A and B
- Two laboratory stands with clamps
Real Lab Procedure
- Take two boiling tubes labelled as A and B.
- Fill up both the tubes with water until they are two-thirds full.
- Insert the plant one by one into each boiling tube.
- Introduce the cotton swabs in such a way that roots dip in water and the stem with leaves project out of the boiling tubes.
- Seal the mouth of the two boiling tubes using adhesive tape such that no water trickles out of the boiling tube even when they are inverted.
- Fix tube A vertically upright in a laboratory stand.
- Fix the other boiling tube B upside down in another laboratory stand.
- Ensure that the water in second tube (B) does not trickle down.
- Place the two laboratory stands near a window such that direct sunlight falls on the two plants.
- Observe the plants in each boiling tube on Day 1, Day 2, Day 3 and day 4.
Simulator Procedure (as performed through the Online Labs)
- Drag and drop one plant to the marked boiling tube A containing water (Make sure that roots dip in water and the stem with leaves project out of the boiling tubes).
- Drag and drop one plant to the marked boiling tube B containing water (Make sure that roots dip in water and the stem with leaves project out of the boiling tubes).
- Drag and drop two cotton swabs into top of the corresponding two boiling tubes.
- Drag and drop adhesive tape into the mouth of two boiling tubes for sealing.
- Drag and drop boiling tube A vertically upright in the laboratory stand.
- Drag and drop boiling tube B upside down in another laboratory stand.
- Click on the next button to go to next screen of simulator.
- You can see the observation of Day 1, Day 2, Day 3, and Day 4 on screen. Corresponding to each day, movement of clock will be shown along with the movement of Plants A and B towards sunlight.
- Click on the ‘Next’ button after Day 4 observation.
- Drag and drop the correct answers from control panel to appropriate places towards the empty boxes.
- If the option dragged is wrong, it will go back to its original place.
- Click on the information icon to see the inference.
- You can redo the experiment anytime by clicking on the ‘Reset’ button.
The stem in test tube A grows vertically upwards and bends towards the light. The stem in test tube B shows a curvature and bends upwards towards the light and away from the gravitational force, thus showing +ve phototropism and –ve geotropism.
The roots in both the test tubes grow towards the gravitational force and grow away from sunlight thus exhibiting -ve phototropism and +ve geotropism.