Plant transport Exam Questions
1. Translocation occurs through the sieve elements by .....................1..................... . Sucrose is
loaded into the phloem at regions of the plant known as .....................2..................... . This
mechanism is .....................3..................... . The addition of sucrose
.....................4..................... the water potential of the sieve element sap. This causes water to
enter from surrounding tissues by .....................5..................... which in turn increases the
.....................6..................... of the sap.
Which words correctly complete the numbered gaps 1–6?
1 2 3 4 5 6
A active transport sources active raises osmosis concentration
B mass flow sources active lowers active transport pressure
C mass flow sinks passive raises diffusion concentration
D mass flow sources active lowers osmosis pressure
[1]
2. The following statements refer to the movement of water from the cortex of the root into the
xylem. Which of the following statements is / are true?
Statement 1: Most of the water moves across the root cortex by the apoplast pathway.
Statement 2: At the endodermis water has to enter the symplast pathway.
Statement 3: Casparian strips in the endodermis contain the chemical lignin.
A. 1, 2 and 3
B. Only 1 and 2
C. Only 1 and 3
D. Only 1
[1]
3. The following passage has four key terms missing:
Meristem cells in plants are used to generate new plant tissues. When
.......................................... tissue is formed, .......................................... impregnates the cell
walls, making them impermeable to water. All cytoplasm is lost. When
.......................................... tissue is formed, cytoplasm remains, but the
.......................................... become elongated and lose most of their cytoplasm.
What is the correct order of missing terms?
A sclerenchyma, phloem, lignin, xylem vessels
B xylem, lignin, parenchyma, phloem vessels
C phloem, collenchyma, xylem, sieve tube elements
D xylem, lignin, phloem, sieve tube elements
4. The following graphs show results from an experiment to investigate the rate of transpiration of
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, the same plant in different environments.
Which graph, A to D, shows the results for when the plant is being grown in the least humid
environment?
5. A diagram of a potometer is shown below.
Which of the following options, A to D, is a precaution that is not needed when setting up a
potometer?
A. Remove excess water from the surface of the leaves before readings are taken.
B. The screw clip must be opened while taking the readings.
C. The shoot should be cut whilst under water.
D. There should be no extra air bubbles.
[1]
6. Below is a light microscope image of a transverse section of part of a plant stem.
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1. Translocation occurs through the sieve elements by .....................1..................... . Sucrose is
loaded into the phloem at regions of the plant known as .....................2..................... . This
mechanism is .....................3..................... . The addition of sucrose
.....................4..................... the water potential of the sieve element sap. This causes water to
enter from surrounding tissues by .....................5..................... which in turn increases the
.....................6..................... of the sap.
Which words correctly complete the numbered gaps 1–6?
1 2 3 4 5 6
A active transport sources active raises osmosis concentration
B mass flow sources active lowers active transport pressure
C mass flow sinks passive raises diffusion concentration
D mass flow sources active lowers osmosis pressure
[1]
2. The following statements refer to the movement of water from the cortex of the root into the
xylem. Which of the following statements is / are true?
Statement 1: Most of the water moves across the root cortex by the apoplast pathway.
Statement 2: At the endodermis water has to enter the symplast pathway.
Statement 3: Casparian strips in the endodermis contain the chemical lignin.
A. 1, 2 and 3
B. Only 1 and 2
C. Only 1 and 3
D. Only 1
[1]
3. The following passage has four key terms missing:
Meristem cells in plants are used to generate new plant tissues. When
.......................................... tissue is formed, .......................................... impregnates the cell
walls, making them impermeable to water. All cytoplasm is lost. When
.......................................... tissue is formed, cytoplasm remains, but the
.......................................... become elongated and lose most of their cytoplasm.
What is the correct order of missing terms?
A sclerenchyma, phloem, lignin, xylem vessels
B xylem, lignin, parenchyma, phloem vessels
C phloem, collenchyma, xylem, sieve tube elements
D xylem, lignin, phloem, sieve tube elements
4. The following graphs show results from an experiment to investigate the rate of transpiration of
© OCR 2017. You may photocopy this page. Page 1 of 9 Created in ExamBuilder
, the same plant in different environments.
Which graph, A to D, shows the results for when the plant is being grown in the least humid
environment?
5. A diagram of a potometer is shown below.
Which of the following options, A to D, is a precaution that is not needed when setting up a
potometer?
A. Remove excess water from the surface of the leaves before readings are taken.
B. The screw clip must be opened while taking the readings.
C. The shoot should be cut whilst under water.
D. There should be no extra air bubbles.
[1]
6. Below is a light microscope image of a transverse section of part of a plant stem.
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