10 Transpiration, transport and
support in plants II
2nd Term WS 11
1
(a) Both tissues are found within vascular
bundles. 1m
Xylem is on the inside while
phloem is on the outside of each bundle. 1m
(b) Cells of sieve tubes are joined end to end /
form continuous structures through the plant. /
Their end walls form sieve plates.
/
They are associated with companion
cells. /
There is a little cytoplasm / few
organelles / no nucleus. (any 2) 1m
x 2
2
(a) X is phloem. 1m
It is responsible for the
transport of organic nutrients in the plant. 1m
Y is xylem. 1m
It is responsible for the
transport of water and minerals in the plant /
provides mechanical support to the
plant. 1m
(b) The fungal spores will be carried upwards. 1m
The fungal spores will be carried
along with the water stream in Y (xylem). 1m
Water stream in Y, which is drawn
up by transpiration pull, always flows upwards. 1m
3
(a) transpiration 1m
xylem 1m
osmosis 1m
stomata 1m
(b) Photosynthesis is essential for plants to
gain energy. /
Gas exchange is needed for
photosynthesis to occur. /
Plants need to open stomata to
exchange gases. /
Some water is lost through the
cuticle. (any 2) 1m
x 2
4.
(a) Xylem: K, Q, X 1m
Phloem: L, P, Y 1m
(b) In the stems, the vascular bundles are
separate and arranged in a ring at the periphery. 1m
In the roots, the vascular bundles are
located at the centre. 1m
(c) On the leaves, there are numerous stomata to
allow gases to diffuse into and out of the leaves.
1m
Roots are not covered with cuticle. Gases
diffuse through their surfaces. 1m
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