A few candidates attempted this question and scored poorly. Most candidates could not correctly label the parts of the drawn transverse section of a stem. Questions (b) and (d) were poorly answered.
The expected answers are:
(a) (ii) Drawing of the T. S. of the stem of a dicotyledonous plant
Quality (Q)
Clarity of Lines (CL) – lines not broken; not wooly
Neatness of labels (NL) – guidelines ruled, labels horizontal
Size (Sz) – 8 – 10cm long
Details (D)
Presence of cortex/collenchymas/parenchyma (PC)
Medullary rays shown (MR)
Shape of vascular bundle (VB)
Labels (L)
Cortex/collenchymas/parenchyma, endodermis, epidermis, pericycle/sclerenchyma, medullary ray, pith, phloem, xylem, cambium. Note: Spellings must be correct to score
(b) Differences between the functions of the vascular tissues of plants and mammalian skeleton
SKELETON |
VASCULAR TISSUES |
-aids breathing |
does not aid breathing; |
-does not conduct water/food |
conducts water/food; |
-aids movement/locomotion in mammals |
does not aid movement/locomotion; |
-protects some vital/delicate parts/organs; |
does not protect vital/delicate parts/organs; |
-composed of bones/cartilage |
composed of dense protoplasm and
lignified walls.
|
Note: Points must correspond to score.
(d) Tropism
The directional growth/response; of plant organ; to external stimulus/light/water/force of gravity.