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.
(a) Three observable features of biological importance
(i) Specimen F (carrot): a swollen fleshy tap root that stores food; presence of small lateral roots; a reduced stem bearing leaf bases at the broad upper end; no buds or scale leaves.
(ii) Specimen G (Irish potato): a swollen fleshy stem storing food; presence of buds (eyes); presence of scale leaves and lenticels.
(b)(i) Classification
Specimen F (carrot): root tuber.
Specimen G (Irish potato): stem tuber.
(b)(ii) Two reasons each
Specimen F is a root tuber because it is a swollen tap root and bears lateral roots, with no buds or scale leaves.
Specimen G is a stem tuber because it bears buds (eyes) and scale leaves, which are features of a stem, together with lenticels.
(c) Class of Specimens H and J: Insecta.
(d)(i) Four observable differences between H and J
Specimen H (mosquito)
Specimen J (cockroach)
Smaller in size
Larger in size
One pair of wings; no hard hind wings
Two pairs of wings; hard hind wings (elytra) present
Shorter antennae
Longer antennae
Cylindrical body with thin legs
Dorso-ventrally flattened body with thick spiny legs
(d)(ii) Four observable similarities between H and J: both have a pair of compound eyes; both have the body divided into head, thorax and abdomen; both have three pairs of jointed legs; both have a pair of antennae and an exoskeleton of chitin.
(e)(i) Feeding habits: Specimen H (mosquito) feeds by piercing and sucking; Specimen J (cockroach) feeds by biting and chewing.
(e)(ii) Two observable feeding features of Specimen J (cockroach): the mandibles and the maxillae (also the labium and labrum).
(a) Three observable features of biological importance
(i) Specimen F (carrot): a swollen fleshy tap root that stores food; presence of small lateral roots; a reduced stem bearing leaf bases at the broad upper end; no buds or scale leaves.
(ii) Specimen G (Irish potato): a swollen fleshy stem storing food; presence of buds (eyes); presence of scale leaves and lenticels.
(b)(i) Classification
Specimen F (carrot): root tuber.
Specimen G (Irish potato): stem tuber.
(b)(ii) Two reasons each
Specimen F is a root tuber because it is a swollen tap root and bears lateral roots, with no buds or scale leaves.
Specimen G is a stem tuber because it bears buds (eyes) and scale leaves, which are features of a stem, together with lenticels.
(c) Class of Specimens H and J: Insecta.
(d)(i) Four observable differences between H and J
Specimen H (mosquito)
Specimen J (cockroach)
Smaller in size
Larger in size
One pair of wings; no hard hind wings
Two pairs of wings; hard hind wings (elytra) present
Shorter antennae
Longer antennae
Cylindrical body with thin legs
Dorso-ventrally flattened body with thick spiny legs
(d)(ii) Four observable similarities between H and J: both have a pair of compound eyes; both have the body divided into head, thorax and abdomen; both have three pairs of jointed legs; both have a pair of antennae and an exoskeleton of chitin.
(e)(i) Feeding habits: Specimen H (mosquito) feeds by piercing and sucking; Specimen J (cockroach) feeds by biting and chewing.
(e)(ii) Two observable feeding features of Specimen J (cockroach): the mandibles and the maxillae (also the labium and labrum).
Study specimen R and answer questions 4(a) to 4(c).
(a) (i) Name the phylum of specimen R. (ii) State two reasons for the answer in 4(a)(i).
(iii) State the habitat of specimen R. (b) (i) State two structural features that adapt specimen R to its habitat. (ii) State three ways in which specimen R is of economic importance.
(c) Make a drawing,8cm- 10cm long of the dorsal view of specimen R and label fully.
Study specimens S and T and answer questions 4(d) to 4(e).
(d) What type of fruits are specimens S and T?
(e) (i) State four observable differences between specimens S and T.
(ii) State three observable similarities between specimens S and T.
4(a)(i) Specimen R belongs to the phylum Annelida.
4(a)(ii) Reasons:
Its long cylindrical body is divided into numerous similar segments (metameric segmentation).
It possesses bristles called chaetae on the body segments.
4(a)(iii) It lives in moist or damp soil, especially under decaying leaves, grasses and other organic matter.
4(b)(i) Structural adaptations to its habitat:
It has chaetae which grip the soil during crawling and burrowing.
Its moist, slimy skin permits gaseous exchange and reduces friction during movement through the soil.
4(b)(ii) Economic importance:
Its burrowing aerates the soil.
Its castings and decomposition activities improve soil fertility.
It is used as bait in fishing.
4(c) Dorsal view of specimen R, with the following labels: prostomium/anterior end, body segments, clitellum, and posterior end (anus).
4(d)
Specimen
Type of fruit
S, unripe mango
Drupe
T, tomato
Berry
4(e)(i) Observable differences between specimens S and T
Specimen S, unripe mango
Specimen T, tomato
Green in colour
Red or yellow in colour
Usually contains one large seed
Contains many small seeds
Has a hard, stony endocarp
Has a soft, succulent endocarp
Has a fibrous mesocarp
Has a soft, juicy mesocarp
4(e)(ii) Observable similarities between specimens S and T
Both are fruits.
Both contain seeds.
Both have a pericarp or fruit wall made up of epicarp, mesocarp and endocarp.
Study specimens C, D and E carefully and answer questions 1(a) to 1(C).
(a) (i) Name the phylum to which specimens C and E belong. (ii) State two reasons for the answer in 1(a)(i).
(b) State three observable structural differences between the following specimens. (i)C and D (ii) C and E.
(C) What is the relationship between specimens C and D?
(d)(i)) Name the habitat of specimen D. (ii) State two ways in which specimen D is adapted to its habitat.
(C) Make a drawing, 8cm - 10cm long of the dorsal view of specimen C and label fully.
(a) (i) Specimens C and E belong to the phylum Arthropoda.
(a) (ii) Reasons:
They have segmented bodies.
They possess jointed appendages and a hard chitinous exoskeleton.
(b) Observable structural differences
(i) Specimens C and D
Specimen C: Butterfly
Specimen D: Caterpillar
Has two pairs of wings.
Has no wings.
Has a long sucking proboscis.
Has biting and chewing mandibles.
Prolegs and claspers are absent.
Prolegs and claspers are present.
(ii) Specimens C and E
Specimen C: Butterfly
Specimen E: Grasshopper
Has a sucking proboscis.
Has biting and chewing mandibles.
Antennae are clubbed or knobbed.
Antennae are tapering and not clubbed.
Wings are soft, membranous and covered with scales.
Wings are firmer and not covered with scales.
Hind legs are relatively short and not adapted for jumping.
Hind legs are long, muscular and adapted for jumping.
(c) Specimen D is the larval stage of specimen C. Specimen C is the adult butterfly, or imago, of specimen D. They are stages in the complete metamorphosis of the same insect.
(d) (i) Specimen D lives on green plants, especially on leaves in gardens, farms and vegetable plots.
(d) (ii) Adaptations of specimen D to its habitat include:
It has strong mandibles for biting and chewing leaves.
It has three pairs of clawed true legs, prolegs and claspers for gripping and climbing on leaves and twigs.
Its body colour and pattern provide camouflage among leaves.
(e) Dorsal view of specimen C, Butterfly
Drawn at a length of 8 to 10 cm and fully labelled:
Dorsal view of an adult butterfly, showing the principal external features.
(a) (i) Specimens C and E belong to the phylum Arthropoda.
(a) (ii) Reasons:
They have segmented bodies.
They possess jointed appendages and a hard chitinous exoskeleton.
(b) Observable structural differences
(i) Specimens C and D
Specimen C: Butterfly
Specimen D: Caterpillar
Has two pairs of wings.
Has no wings.
Has a long sucking proboscis.
Has biting and chewing mandibles.
Prolegs and claspers are absent.
Prolegs and claspers are present.
(ii) Specimens C and E
Specimen C: Butterfly
Specimen E: Grasshopper
Has a sucking proboscis.
Has biting and chewing mandibles.
Antennae are clubbed or knobbed.
Antennae are tapering and not clubbed.
Wings are soft, membranous and covered with scales.
Wings are firmer and not covered with scales.
Hind legs are relatively short and not adapted for jumping.
Hind legs are long, muscular and adapted for jumping.
(c) Specimen D is the larval stage of specimen C. Specimen C is the adult butterfly, or imago, of specimen D. They are stages in the complete metamorphosis of the same insect.
(d) (i) Specimen D lives on green plants, especially on leaves in gardens, farms and vegetable plots.
(d) (ii) Adaptations of specimen D to its habitat include:
It has strong mandibles for biting and chewing leaves.
It has three pairs of clawed true legs, prolegs and claspers for gripping and climbing on leaves and twigs.
Its body colour and pattern provide camouflage among leaves.
(e) Dorsal view of specimen C, Butterfly
Drawn at a length of 8 to 10 cm and fully labelled:
Dorsal view of an adult butterfly, showing the principal external features.
