Topic 9.1 Practice Q's
[11 marks]
1. A fungicide dissolved in water was applied to the soil in which a rose
[1 mark]
plant was growing. It later appeared in the leaves. How did the fungicide
reach the leaves?
A. Movement up a water potential gradient
B. Transpiration pull in xylem
C. Translocation in phloem
D. Facilitated diffusion
2. How do water molecules enter root cells?
A. Transpiration
B. Tension
C. Capillary action
D. Osmosis
[1 mark]
3. Which process and cause are responsible for water uptake by the roots?
[1 mark]
4. Excessive irrigation can cause increased salinity in the soil. What effect
does this have on water transport in the plant roots?
[1 mark]
A. Decreases movement of water from soil into the root
B. Absorption of water with a higher solute concentration
C. Increases movement of water from soil into the root
D. Absorption of water with a lower solute concentration
5. Which is the most efficient way for some desert plants to conserve water? [1 mark]
A. By having no leaves, so water evaporates from the green stem with less
surface
B. By loading organic compounds in the phloem of the roots
C. By accumulating salt within their tissues, so water is retained by osmosis
D. By growing long hair on their surface, so air moisture is absorbed at night
6. What is transported in xylem tissue?
A. Sucrose from leaves to fruits
B. Starch from leaves to storage organs
C. Water from roots to leaves
D. Salts from soil to roots
[1 mark]
7. In the micrograph of a plant stem, which letter indicates the xylem?
[1 mark]
[Source: adapted from
Kelvinsong/https://creativecommons.org/licenses/by/3.0/deed.en]
8. Cobalt chloride paper is blue when dry but turns pink with water. Blue
[1 mark]
cobalt chloride paper was fastened to the upper and lower surfaces of a
plant leaf. After 20 minutes, many small pink dots were observed on the paper on
the lower surface, and a few pink dots were seen on the upper surface. What
conclusions can be drawn?
I. There are more stomata on the lower surface than on the upper surface.
II. Stomata on the upper surface are blocked by the waxy cuticle.
III. More transpiration occurs through the lower surface than through the upper
surface.
A. I and II only
B. I and III only
C. II and III only
D. I, II and III
9. Vascular plants can be found in a wide variety of ecosystems.
[3 marks]
Explain how a plant replaces the water it loses in transpiration.
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