Question 18M.2.SL.TZ2.3
| Date | May 2018 | Marks available | [Maximum mark: 9] | Reference code | 18M.2.SL.TZ2.3 |
| Level | SL | Paper | 2 | Time zone | TZ2 |
| Command term | Distinguish, Explain, Outline, State | Question number | 3 | Adapted from | N/A |
The electron micrograph shows a palisade mesophyll cell.
State the name of the structures labelled I and II.
[1]
I. cell wall
II. nucleus/chromatin
Both needed.
Outline the function of the structure labelled III.
[2]
a. necessary for photosynthesis/converts light energy into chemical energy
b. contains chlorophyll to absorb light
c. (contains enzymes) for production of carbohydrate/glucose/starch
The plant from which this cell was taken is in the group angiospermophyta. State one characteristic that is unique to this group of plants.
[1]
a. produce flowers
b. enclosed seeds/have fruit
Distinguish between autotrophic nutrition and heterotrophic nutrition.
[2]
Table format not required.
Must be paired statements.
Explain how energy and nutrients are transferred in ecosystems.
[3]
a. energy enters ecosystems from the Sun / continuous supply from the Sun
b. light energy is converted into chemical energy and lost with movement along food chains
OR
energy needs to be «constantly» added «to ecosystem» as lost with movement along food chains / energy lost as heat with movement along food chains
c. nutrients are recycled within ecosystems / nutrients in an ecosystem are finite and limited
d. nutrients not lost but transformed into different compounds
e. nutrients «carbon compounds»/energy flow through food chains by means of feeding
