Question 1
Why do root hair cells have long extensions?
- to increase the surface area for absorption
- to store water
- to carry out photosynthesis
- to transport sucrose
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Answer: A (1)
Question 2
State two functions of root hair cells and explain how the root hair is adapted to carry them out.
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- absorb water (1)
- absorb mineral ions (1)
- long extension / root hair gives a large surface area (1)
Question 3
Outline the pathway taken by water from the soil to the mesophyll cells of a leaf.
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- enters root hair cells (from soil) (1)
- moves through root cortex cells (1)
- enters and moves up the xylem (1)
- (from xylem in the leaf) to mesophyll cells (1)
Question 4
Which list shows the pathway of water through a plant in the correct order?
- xylem, root hair cell, root cortex, mesophyll
- root hair cell, root cortex, xylem, mesophyll
- root cortex, root hair cell, mesophyll, xylem
- mesophyll, xylem, root cortex, root hair cell
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Answer: B (1)
Question 5
A student places a freshly cut stem of a white flower in water containing a red stain. After 24 hours the petals have red veins. Describe how the student could use the stem to show where water travels, and state what they should see.
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- cut a thin transverse section (of the stem) (1)
- view with a hand lens / microscope (1)
- red stain seen in small areas / the vascular bundles (1)
- these are the xylem, so water moves in the xylem (1)
Question 6
Suggest two variables the student should control when comparing the uptake of stain in two different plants.
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- same type / species / size of plant (1)
- same volume / concentration of stain (1)
- same time / temperature / light (1)
- Max 2