Table 2.1
| time/mins | test-tube A | test-tube B | test-tube C |
|---|---|---|---|
| 0 | black | black | black |
| 1 | black | black | dark brown |
| 2 | black | black | dark brown |
| 3 | dark brown | black | lighter brown |
| 4 | dark brown | black | lighter brown |
| 5 | dark brown | black | yellow brown |
| 6 | light brown | black | yellow brown |
| 7 | lighter brown | black | yellow brown |
| 8 | lighter brown | black | yellow brown |
| 9 | lighter brown | black | yellow brown |
| 10 | yellow brown | black | yellow brown |
(a) (i) State how long it took for the starch to be completely broken down in test-tubes A and C.
Answer (1)
To determine how long it took for the starch to be completely broken down in test-tubes A and C, we need to analyze the color change data provided in the table.
In the context of this experiment, the color changes from black to yellow-brown typically indicate the breakdown of starch. This is likely part of a study on enzyme activity, where enzymes like amylase break down starch into simpler sugars, resulting in a color change.
Test-tube A:
At time 0 minutes, the color is black.
The color transitions to light brown by 6 minutes, lighter brown by 7-9 minutes, and finally yellow brown by 10 minutes.
Thus, it took 10 minutes for the starch to be completely broken down in test-tube A as indicated by the final yellow-brown color.
Test-tube C:
At time 0 minutes, the color is black as well.
By 3 minutes, the color changes to lighter brown and at 5 minutes, it is yellow brown, indicating complete breakdown.
Therefore, it took 5 minutes for the starch to be completely broken down in test-tube C.
In summary:
Test-tube A: The starch was completely broken down in 10 minutes.
Test-tube C: The starch was completely broken down in 5 minutes.
This information is crucial in understanding how different conditions, such as enzyme concentration or temperature, may affect the rate of starch breakdown.
