Study carefully specimens J, K and L and use them to answer questions 4(a) to 4(d).
(a)(i) State the class of each of specimens J, K and L
(ii) State three reasons each for placing each of specimens J, K and L in their classes.
(b) State two structural adaptations possessed by each of specimens K and L for escaping predators.
(c) Make a drawing, 8 – 10cm long of the lateral view of specimen J.
(d) State: (i) two similarities; (ii) two observable differences between specimens J and L.
Explanation
(a) Class of Specimen J-Tilapia: Osteichthyes.
Reason: Body is covered with scales. (ii) Presence of paired fins. (iii) Presence of lateral line(s). (iv) Presence of operculum/gill cover.
class of Specimen K/Toad: Amphibian
Reason: (i) Presence or warty skin. (ii) Presence or webbed digits. (iii) Presence of moist skin. (iv) Presence of bulging eyes. (v) Presence of ear drum.
Structural adaptations for escaping predation: Specimen K/Toad:Presence of poison gland on skin which secretes a substance which irritates/repels the predators.
(i) Counter shading of the dorsal and ventral sides/camouflage facilitate escape from predator.
(ii)Long hind limb and short muscular forelimb ror jumping away from predator.
Class of Specimen L/Lizard : Reptilla
Reason: Presence of dry horny scales on skin (ii) presence of fore and hind limbs with clawed digits. (iii) Homodont dentition. (iv) Well developed retractable tongue.
Specimen L/Lizard:Detachable tail to escape from predators. (ii) Skin color blends with surrounding/camouflage to enhance escape from predators. (iii) Eyes for seeing predators. (iv) Limbs for running away from predators.
(c) Drawing Specimen J/Tilapia:
(d)(i) Similarities between Specimen J& L: (i) Presence of eyes. (i) Presence of nostrils. (ii) Presence Or Scales. (v) Presence of head. (v) Presence of tail.
Differences
(ii)
|
J/Tilapia |
L/Lizard |
|
Presence of fins |
Presence of limbs |
|
Absence of tympanum |
Presence of tympanum |
|
Lateral line present |
Lateral line absent |
|
Short tail |
Long tail |
|
Presence of operculum/gill cover |
No operculum/gill cover |