Question 20N.3.HL.TZ0.a
| Date | November 2020 | Marks available | [Maximum mark: 1] | Reference code | 20N.3.HL.TZ0.a |
| Level | HL | Paper | 3 | Time zone | TZ0 |
| Command term | State | Question number | a | Adapted from | N/A |
Sodium alginate beads were prepared containing a suspension of Chlorella algae. These beads were placed in nine small jars containing hydrogencarbonate indicator solution. Hydrogencarbonate indicator is commonly used to detect changes in pH.
The jars were placed at different distances from a lamp, which was the only light source. The distances ranged from 40 to 130 centimetres. Jars were placed one at a time to avoid the jars from shading each other. Colour changes were observed.
[Source: © International Baccalaureate Organization 2020.]
State the name of the process which occurs in the chloroplasts of Chlorella, that uses CO2.
[1]
photosynthesis/light independent reaction (of photosynthesis)
Candidates generally stated photosynthesis, or light independent reaction of photosynthesis.
