This was the more popular question in this section and candidates generally performed better
Most candidates would not state the mode of nutrition of specimen D. – parasitic and a few candidates who could lost marks due to spelling errors.
The candidates however performed well on 2b in which they were required to state the economic importance of specimens C,D and E.
The candidates could also correctly state observable features of specimen E/rat that are sensory in nature as well as state two observable differences between specimens C and D.
However, they had problems in classifying the specimens into their phyia and classes as well as stating the characteristic features of the classes, few candidates who did had problems with spelling errors
Expected answers include:
(b)(i) Classification of
Specimen Plylum Class
C Arthropoda Insecta
D Arthropoda Arachnida
E Chordata Mammalia
(ii). Observable characteristics of
Class Arthropoda/ Specimen C
- three body divisions/head, thorax and abdomen;
- presence of 6 jointed/3 pairs of jointed walking leg;presence of compound eyes;
- presence of segmented thorax/prothorax, mesothorax and metathorax;
- presence of wings;
- Presence of a pair of compound eyes;
- Presence of a pair of antennae.
Class Arachnida/Specimen D
- 8 jointed/4 pairs of legs;
- 2 body divisions/Cephalothorax and Abdomen;
- Presence of simple eyes/ocelli;
- Presence of two appendages for feeding/pedipalps and chelicerae.
Class Mammalia/ Specimen E
- - Presence of hair/fur on body;
- - Presence of external ears/pinnae;
- - Presence of mammary glands;
- - Presence of four limbs for locomotion;
- - Heterodont dentition.
