Question 18M.2.SL.TZ1.4
| Date | May 2018 | Marks available | [Maximum mark: 7] | Reference code | 18M.2.SL.TZ1.4 |
| Level | SL | Paper | 2 | Time zone | TZ1 |
| Command term | Identify, Outline, State | Question number | 4 | Adapted from | N/A |
State one reason that viruses are not classified as living organisms.
[1]
a. they do not have a metabolism/homeostasis/other specifically named life function
b. cannot reproduce by themselves
c. they are not cells/they need a host cell
State the plant phylum which is characterised by the absence of vascular tissue.
[1]
bryophyta
C. nemoralis (pictured below) is a mollusc. Identify two external features that distinguish this snail from an arthropod.
[2]
a. unsegmented body (whereas arthropods are segmented)
b. shell (versus exoskeleton in arthropods)
c. muscular foot (which arthropods do not have)
d. no (jointed) appendages/(jointed) legs (whereas arthropods have jointed legs/appendages)
e. slimy/mucus-covered / arthropod is not slimy
Do not award marks for any answers after the first two given.
Outline the role of plant pigments in the process of photosynthesis.
[3]
a. pigments/chlorophyll absorb light
b. red and blue/violet light absorbed
c. absorption of light energy is necessary for photolysis/use of water in photosynthesis
d. other pigments allow for wider action spectrum than the absorption spectrum of chlorophyll
