(a)[2]
Explain why the light microscope rather than the electron microscope is used to observe the movement of Chlamydomonas.
(b(i))[1]
State one function of magnesium ions in photosynthetic organisms.
(b(ii))[2]
State two properties of water that enable organisms such as Chlamydomonas to live in water.
(c)[4]
Explain why multicellular organisms need transport systems, whereas unicellular organisms such as Chlamydomonas do not.
(d)[5]
Some plants, including the banana plant, Musa acuminata, produce fruit. The banana fruit contains a high proportion of carbohydrate. Describe how sugars are transported in phloem sieve tubes from source to sink in plants such as M. acuminata.