Question 3
The diagrams below are illustrations of two organisms. Study them and answer question 3 (a) to (f)
(a)(i) Identify organisms A and B. [2 marks]
(ii) Name the parts labeled I to X. [5 marks]
(b) State one function each of the parts labeled VI, VIII, IX and X. [4 marks]
(c) Name the specific habitats of organisms A and B. [2 marks]
(d) State three structural adaptations of organism A to its mode of life. [6 marks]
(e)(i)State three structural similarities between organisms A and B. [3 marks]
(ii) State three structural differences between organisms A and B. [3 marks]
(f)(i) Name the class of organisms A and B. [1 marks]
(ii) State three reasons for the answer in 3 (f) (i). [3 marks]
(g)State one biological importance of organism A. [1 marks]
Observation
This question required candidates to identify the butterfly and housefly; name the labelled parts; state the functions of the parts; name their habitats; state similarities and differences between them; state their Class and give reasons for the classification.
Many candidates lost marks because they spelt butterfly and housefly as two words as in butter fly and house fly. Many candidates could not state the structural adaptation of butterfly and housefly properly. They either stated the structure only or the function only.
Many candidates could not also start the name of the class of the organisms in Capital letter which made them lose marks.
Also, majority of the candidates could not spell ‘pollination’ correctly.
The expected answers are:
(a) (i) Identification of organisms
A – Butterfly/Papilio sp.
B – Housefly/Musca sp.
(ii) Name of labelled parts
I- Head; VI- Antenna;
II- Antenna; VII- Head;
III- Thorax; VIII- Compound eye;
IV- Fore(wing); IX- fore (wing);
V- Abdomen; X- leg.
Note: Wrongly qualified parts should not score e.g. hind wing/ fore leg.
(b) Function of parts
VI - Antenna: for feeling/ sensitivity (to touch/smell/vibrations);
VIII - Compound eye: for seeing/ sight/vision;
IX - wing: for balancing/flying/ flight;
X - leg: for walking/ crawling/ running.
(c) Specific habitats of organisms A and B
A /Butterfly: Garden, farm/ flowering plants/ trees;
B /Housefly: Latrines/ toilets/ refuse dumps/ exposed food/ sewage/ decaying organic . matter.
(d) Structural adaptations of organism A
- Large/ broad wings; for flight;
- Long thin proboscis/mouthpart; for sucking nectar;
- Long clubbed antennae; for sensitivity;
- Large compound eyes; for vision .
Note: The structure must be correctly qualified to score; but 1mark will be awarded for correct function.
(e) (i) Structural similarities between organisms A and B
Both possess
- Wings;
- Three body divisions/head, thorax and abdomen;
- A pair of antennae;
- A pair of compound eyes.
- Segmented body
(ii) Structural differences between organisms A and B
A/Butterfly |
B/Housefly |
Broad wings |
Narrow wings; |
Antennae is clubbed/knobbed |
Antennae is not clubbed/knobbed; |
Long antennae |
Short antennae; |
Smaller compound eyes |
Bigger compound eyes; |
Scales present |
Scales absent; |
Hind wings present |
Hind wings reduced to halters; |
Simple eyes absent |
Simple eyes present; |
Hair absent |
Hair present; |
(f) (i) Class of organisms A and B
Insecta
(ii) Reasons for the answer in (f) (i)
- Presence of wings;
- Three body divisions/ head, thorax and abdomen;
- A pair of antennae;
- Three pairs of jointed legs (on the thorax);
- Presence of a pair of compound eyes;
- Segmented body.
(g) Biological importance of organism A
- It pollinates flowers;
- It is a source of food for some organisms.