Most candidates could properly identify the Organism in A as Paramecuim but a few of them missed the spelling and so lost some marks. Most candidates correctly identified the organism as being as the cellular level of organization and could state that the organism reproduces by conjugation. Areas where the candidates had difficulty include stating the functions of the contractile vacuole, micronucleus, cytostome and outlining similarities and difference between the Amoeba and the Paramecium.
Expected answer include:
Function of IV, VI and VIII
IV - Osmoregulation/Controlling water content
VI - Responsible for reproduction/production of macronucleus
VII - Serves as mouth/for ingestion of food.
Observable Similarities in A and B
- both have: food vacuole
- ectoplasm/cytoplasm
- endoplasm/cytoplasm
- contractile vacuole
- nucleus
- both are unicellular.
(iii) Observable Differences in A and B
A/Paramecium |
B/Amoeba |
| - Two nuclei/macronuclei & micronuclei |
- One nucleus. |
| - Presence of cilia |
- Absence of cilia |
- Absence of pseudopodia |
- Presence of pseudopodia |
| - Presence of pellicle |
- Absence of pellicle/presence of cell membrane |
| - Presence of oral groove/gullet |
- Absence of Oral groove/gullet |
| - Two contractile vacuoles |
- One Contractile vacuole |
- Presence of gullet |
- Absence of gullet |
| - Presence of trichocysts |
- Absence of trichocyst |
- Presence of cytostome |
- Absence of cytostome |
