Question 18M.2.HL.TZ1.7b
| Date | May 2018 | Marks available | [Maximum mark: 4] | Reference code | 18M.2.HL.TZ1.7b |
| Level | HL | Paper | 2 | Time zone | TZ1 |
| Command term | Outline | Question number | b | Adapted from | N/A |
Outline how plants make use of the different wavelengths of light.
[4]
a. light used in photosynthesis/light-dependent reactions/photolysis/photosystems/photophosphorylation/excitation of electrons/switch to flowering
b. chlorophyll absorbs red AND blue light (more)
c. chlorophyll/leaf/plant reflects/does not absorb/does not use green light
d. absorption spectrum of chlorophyll has peaks in the red and blue/sketch graph to show this
e. action spectrum shows which wavelengths plants use in photosynthesis/sketch graph of action spectrum showing peaks in the blue and red
f. accessory/other (named) photosynthetic pigments absorb different wavelengths/colours
g. violet is the shortest wavelength and red the longest
h. red light and far red/infra-red absorbed to measure length of light/dark periods
