Study specimens L, M, N, P, Q, R and S carefully and use them to answer questions 4(a) to 4(d).
(a) Name two specimens which can be used for the following: (i) transaction; (ii) protection; (iii) statement.
(b) Stating observable features in specimens L, M, N, P,Q and R, Suggest one reason each for the answers given in 4(a)i), (ii) and (iii) above.
(c) State. (i) two observable similarities; (ii) two differences between specimens P and R.
(d)(i) Sate how observable features of specimen M adapt the specimen to its functions.
(ii) Arrange specimens L, , N and S in the increasing order of complexity of the organism to which they belong.
(a) Two specimens for each function
(i) Reproduction: specimen P (Irish potato) and specimen R (cassava cutting) [also Q, the Hibiscus twig].
(ii) Protection: specimen L (goat skin) and specimen N (snail shell) [also M, the feather].
(iii) Movement: specimen M (quill feather) and specimen S (hind wing of cockroach).
(b) Observable feature and reason for each choice
Reproduction:
P (Irish potato): bears buds (eyes) that sprout to produce new shoots.
Q (Hibiscus twig): bears buds that sprout to form new plants.
R (cassava cutting): bears nodes with buds that sprout to produce new shoots.
Protection:
L (goat skin): a hairy, sheet-like covering that protects the body against mechanical injury.
M (feather): broad and smooth, it covers the body, prevents wetting and provides insulation.
N (snail shell): hard and calcareous, it protects the soft body of the snail.
Movement:
M (feather): the wing and tail feathers are flat and air-tight, providing surface for flight.
S (cockroach hind wing): light and flexible, providing surface for flight.
(c)(i) Two similarities between P and R
Both are modified stems.
Both bear buds used for vegetative reproduction (and both possess lenticels).
(c)(ii) Two differences between P and R
Specimen P (Irish potato)
Specimen R (cassava cutting)
Buds are buried in the tuber and covered by scale leaves
Buds protrude on the stem and are not covered
It is a swollen stem that stores food
It is a slender stem that does not store food
(d)(i) How features of specimen M (feather) adapt it to its function: the vane is broad and stiff, giving a large air-tight surface that withstands air pressure and provides lift during flight; the barbs are interlocked by barbules to keep the vane firm; and the quill (calamus) is light, hollow and waterproof, giving buoyancy and keeping the bird dry.
(d)(ii) Increasing order of complexity of specimens L, M, N and S: S (cockroach) → N (snail) → M (bird) → L (goat/mammal).
(i) Reproduction: specimen P (Irish potato) and specimen R (cassava cutting) [also Q, the Hibiscus twig].
(ii) Protection: specimen L (goat skin) and specimen N (snail shell) [also M, the feather].
(iii) Movement: specimen M (quill feather) and specimen S (hind wing of cockroach).
(b) Observable feature and reason for each choice
Reproduction:
P (Irish potato): bears buds (eyes) that sprout to produce new shoots.
Q (Hibiscus twig): bears buds that sprout to form new plants.
R (cassava cutting): bears nodes with buds that sprout to produce new shoots.
Protection:
L (goat skin): a hairy, sheet-like covering that protects the body against mechanical injury.
M (feather): broad and smooth, it covers the body, prevents wetting and provides insulation.
N (snail shell): hard and calcareous, it protects the soft body of the snail.
Movement:
M (feather): the wing and tail feathers are flat and air-tight, providing surface for flight.
S (cockroach hind wing): light and flexible, providing surface for flight.
(c)(i) Two similarities between P and R
Both are modified stems.
Both bear buds used for vegetative reproduction (and both possess lenticels).
(c)(ii) Two differences between P and R
Specimen P (Irish potato)
Specimen R (cassava cutting)
Buds are buried in the tuber and covered by scale leaves
Buds protrude on the stem and are not covered
It is a swollen stem that stores food
It is a slender stem that does not store food
(d)(i) How features of specimen M (feather) adapt it to its function: the vane is broad and stiff, giving a large air-tight surface that withstands air pressure and provides lift during flight; the barbs are interlocked by barbules to keep the vane firm; and the quill (calamus) is light, hollow and waterproof, giving buoyancy and keeping the bird dry.
(d)(ii) Increasing order of complexity of specimens L, M, N and S: S (cockroach) → N (snail) → M (bird) → L (goat/mammal).
Study specimens E, F, G1 and G2 carefully and use them to answer questions 2(a) to 2(d).
(a)(i) Name the life process in mammals that is associated with specimens E.
(ii) State two structural similarities between the surface of specimen E and the skin of specimen F.
(b)(i) Name the habitat in which specimen F will function efficiently.
(ii) Explain how two observable features of specimens F adapt the organism to its habitats.
(C)(i) Using the blade provided cut a thin transverse section of the stem of specimens G add two drops of freshly prepared iodine solution to the cut section.
Record your observation and inferences :
(ii) In which part of the stem is food stored.
(iii) Name two tissues used for transportation of materials in specimens G,
(iv) List two supporting tissues present in specimen G,
(d) Make a drawing 10-12 cm long of a cut transverse section of the stem of specimen G, and label fully.
(a)(i) The life process associated with specimen E in mammals is respiration, that is, gaseous exchange.
(a)(ii) Similarities between the surface of specimen E and the skin of specimen F are:
Both surfaces are thin.
Both are moist and richly supplied with blood capillaries.
(b)(i) Specimen F functions efficiently in a moist terrestrial habitat, usually near ponds or other water bodies.
(b)(ii) Observable adaptive features of specimen F include:
Its moist skin permits gaseous exchange through the skin.
Its long, muscular hind limbs and webbed toes enable it to hop on land and swim in water.
(c)(i)
Observation
Inference
The cortex of the transverse section turns blue-black with iodine solution.
Starch is present in the cortex.
(c)(ii) Food is stored in the cortex, especially in the cortical parenchyma.
(c)(iii) The transport tissues are xylem and phloem.
(c)(iv) Two supporting tissues present are collenchyma and sclerenchyma.
(d) Transverse section of the stem of specimen G
A fully labelled transverse section of the stem of specimen G.
Title: Transverse section of a dicotyledonous stem (specimen G).
