Study specimens F and G carefully and answer questions 2(a) and 2(b).
(a) State three observable features of biological importance in: (i) specimen F; (ii) Specimen G.
(b) (i) Classify specimens F and G as either stem tuber or root tuber. (ii) Give two reasons each for the answer in 2(b)(i).
Study specimens H and J and answer questions 2(c) to 2(e).
(C) Classify specimens H and J into the class to which both belong.
(d) (i) state four observable differences between specimens H and J. (ii) State four observable similarities between specimens H and J.
(e) (i) State the feeding habits of each of specimens H and J. (ii) Name two observable features used for feeding in specimen J.
Explanation
(bi. Classification of Specimen F/Carrot Root tuber
Specimen G / lrish potato Stem tuber
ii. Reasons for classification Specimen F/Carrot -Swollen tap root - lateral roots present has a reduced stem (above the swollen tap root).
Specimen G / irish potato swollen stem/ tuber -presence of bud(s)/eye -presence of scale leaves/leaf -presence of lenticel(s).
(c) Class of specimens H and J Insecta
(d(i). Observable differences between specimens Hand J
|
H/adult mosquito |
J/adult cockroach |
|
- smaller in size |
big/large in size |
|
-a pair of wings |
two pairs of wings |
|
-absence of hard hind wing |
presence of hard hind wing/elytra |
|
-shorter antennae |
longer antennae |
|
-proboscis |
mandible |
|
absence of maxillary palp/maxilla |
presence of maxillary palp/maxilla |
|
- body is cylindrical |
body is dorso-ventraly flattened |
|
-thin legs |
thick large legs |
|
-absence of spines on legs |
presence of spines on legs |
ii. Similarities between specimens H adult mosquito and J/ adult cockroach:
-presence of a pair of compound eyes -body is divided into three divisions/head, thorax and abdomen - three pairs of /six (walking) legs
- presence of jointed appendages -presence of a pair of membraneous wings -presence of a pair of antennae
-both have exoskeleton made of chitin -segmented body
(e) Feeding habit of Specimen H / adult mosquito -piercing and sucking Specimen J / adult cockroach Biting and chewing.
(ii) Observable features used for feeding in specimen J adult /cockroach Mandible; maxillae; labium; labrum