Most candidates identified A and B correctly as the queen termite and soldier
termite but a few candidates got the answers wrong they identify A as centiped
and B as aphid.
Most candidates performed poorly on naming of the parts and many candidates
who made fair attempts, lost marks due to wrong spellings. Only a few candidates could state four observable structural differences between A and B , the phylum and class to which A belongs to and characteristics of the class. In stating
the observable features of A and B which adapt them to their mode of life, many
candidates could state the features e.g. distended abdomen of the queen etc but
could not relate it to the functions.
Expected answers include:
Name of parts
I - Compound Eye. IV - Hardened cuticle.
II - Spiracle. V - Antenna.
III - Abdomen. VI - Powerful jaw/
mounthpart/Mandible.
Structural differences between A & B |
A/Queen |
B/Soldier |
- Distended/large abdomen; |
- Small abdomen; |
- Small head; |
- Large head; |
- Mandible absent; |
- Presence of powerful mandibles; |
- Conspicuous spiracles; |
- No spiracles seen/invisible spiracle/spiracles absent (in diagram) |
- Patches of hardened cuticle present; |
- Patches of hardened cuticle absent; |
Eye present. |
- Eye absent |
Phylum & Class of A
- Phylum - Arthropoda;
- Class - Insecta;
Characteristics of the Class Insecta
- Body covered with exoskeleton made of chitin;
- Body up of head, thorax and abdomen/3 – body division;
- Presence of jointed appendages;
- Head bears a pair of jointed antennae;
- Thorax made up of 3 segments/pro-thorax and meta-thorax;
- Thorax bears one or two pairs of wings;
- 3 pairs of jointed legs;
- Abdomen is segmented;
- Presence of spiracles on abdomen.
Observable adaptive features of
Queen
- Presence of eye; to see
- Large/distended abdomen; to carry many eggs
Soldier
- Presence of antenna; to detect intruder/changes in the termitarium;
- Large/powerful mandibles; for defence/offence.
Most candidates performed better on the second part of question as they could correctly state how specimen A/termite is of economic importance, the type of metamorphosis which undergoes and two examples of other insect which also undergo the same type of metamorphosis;