Exam code: 0610 & 0970
1 markThe diagram below shows a potted plant and the same plant 48 hours later.
What has caused the plant’s appearance to change?
Water loss by translocation is greater than water uptake.
Water evaporating from the leaves by translocation.
Water loss by transpiration is greater than water uptake.
Water loss from the leaves by osmosis.
Did this page help you?
1 markWhich order below is correct in describing the pathway of water as it travels from the roots through a plant?
Root hair cell → xylem → mesophyll cells → air spaces → stomata
Root hair cell → xylem → air spaces → mesophyll cells → stomata
Root hair cell → mesophyll cells → phloem → stomata
Root hair cell → mesophyll cells → xylem → stomata
Did this page help you?
1 markWhich of the following is a correct explanation of the process of translocation in a plant?
The movement of mineral ions through the xylem of a plant.
The movement of sucrose and amino acids through the phloem from a source to a sink.
The one-way movement of sucrose and amino acids through the phloem.
The movement of sucrose and amino acids through the phloem from a sink to a source.
Did this page help you?
1 markThe diagram shows a simplified water cycle.
Which of the processes listed below would be involved in the loss of water from the tree?
Respiration
Translocation
Photosynthesis
Evaporation
Did this page help you?
1 markA potometer can be used to measure the rate that a piece of plant transpires under various conditions.
Part of a potometer is shown in the diagram below.
Which statement, relating to how a potometer works, is false?
A potometer uses the transpiration stream to produce movement of an air bubble that can be measured.
In a potometer, an air bubble moves away from the piece of plant tissue that is under investigation.
In order to determine the rate of transpiration, the movement of the bubble must be measured alongside the time taken.
The leaves of the plant in the potometer must be dry during the experiment.
Did this page help you?
The diagram shows part of a cross-section of a root.
What are cells 1, 2 and 3?
1 | 2 | 3 | |
A | root cortex cell | root hair cell | mesophyll cell |
B | root hair cell | root cortex cell | xylem |
C | root hair cell | root cortex cell | mesophyll cell |
D | root cortex cell | root hair cell | xylem |
Did this page help you?
1 markA dicot plant is placed into a bowl of water coloured with red dye.
After 1 hour, a cross section of one of the roots is cut.
After 4 hours, a cross section is cut from the stem.
Which labelled regions would be stained red in each case?
1 and 3
1 and 4
2 and 4
2 and 3
Did this page help you?
1 markWhich of the following is a correct explanation of the effect of root hairs on absorption?
Provide a large surface area, maximising the rate of absorption of water and ions by osmosis.
Provide a large surface area, maximising the rate of absorption of water by osmosis and ions by active transport.
Increase the surface area, maximising the uptake of water by osmosis and ions by diffusion.
Provide a surface area, increasing the rate of absorption of water and ions by active transport.
Did this page help you?
1 markWhich of the following processes is/are involved in the loss of water from the leaves of plants?
diffusion
osmosis
condensation
evaporation
1 and 3
1 only
4 only
1 and 4
Did this page help you?
1 markA student collected some of the solution from the phloem in the stem of a plant.
Which of the following would be present in the liquid?
Glucose
Starch
Amino acids
Cellulose
Did this page help you?
1 markA decrease in which of the following factors would normally cause the transpiration rate to increase?
Stomatal density
Light intensity
Temperature
Humidity
Did this page help you?
1 markWhich environmental factor is most likely to be responsible for a plant to wilt?
A decrease in light intensity.
An increase in humidity.
A decrease in the amount of available water.
A decrease in wind speed.
Did this page help you?
A plant shoot is placed in a solution of dye.
The dye moves up the stem.
Under which conditions will the dye move most slowly?
temperature | humidity | |
A | high | high |
B | high | low |
C | low | high |
D | low | low |
Did this page help you?
1 markThe xylem has specific adaptations to allow it to transport water and mineral ions from the roots of a plant to the leaves as a result of transpiration.
Which processes produce the adaptations in xylem vessels to allow the continuous flow of water?
| cell walls break down between adjacent cells | cytoplasm and organelles removed from each cell |
A | ✘ | ✘ |
B | ✓ | ✓ |
C | ✘ | ✓ |
D | ✓ | ✘ |
Did this page help you?
1 markWhich of the following graphs correctly shows the relationship between the rate of transpiration and atmospheric humidity?
Did this page help you?
1 markThe diagram below shows two shoots at the start of an experiment set up by a group of students.
What are the most likely readings on the spring balances after four days?
| Spring balance readings / g | |
shoot A | shoot B | |
A | 40 | 40 |
B | 40 | 34 |
C | 34 | 40 |
D | 34 | 34 |
Did this page help you?
1 markThe table below shows some characteristics of four different plants.
The plants are growing in the same environmental conditions.
Which plant will have the lowest rate of transpiration?
| number of leaves on plant | average surface area of one leaf / cm2 | average density of stomata on leaves / stomata per mm2 | average diameter of one stoma / µm |
A | 36 | 53 | 276 | 19 |
B | 21 | 51 | 247 | 18 |
C | 24 | 45 | 249 | 15 |
D | 17 | 40 | 151 | 16 |
Did this page help you?
1 markWhich row of the table below shows substances transported through the phloem and xylem, and the direction of transport, correctly?
| phloem | direction of transport | xylem | direction of transport |
A | sucrose | bi-directional (up and down) | water and mineral ions | bi-directional (up and down) |
B | sucrose | unidirectional (up) | water and mineral ions | bi-directional (up and down) |
C | sucrose and amino acids | bi-directional (up and down) | water | unidirectional (up) |
D | sucrose and amino acids | unidirectional (up) | water | unidirectional (up) |
Did this page help you?
The photomicrograph shows a cross-section through the root of a buttercup plant.
What is the main function of the tissue labelled Z?
Photosynthesis
Respiration
Transport of sugars
Transport of water
Did this page help you?
The diagram shows two shoots at the start of an experiment on transpiration.
What are the likely readings on the spring balances after three days?
shoot X/g | shoot Y/g | |
|---|---|---|
A | 25 | 30 |
B | 25 | 25 |
C | 30 | 25 |
D | 30 | 30 |
Did this page help you?
Roots and leaves both act as sources and sinks for sucrose and amino acids at different times during the year.
At which point in the year are the roots most active as a source?
Did this page help you?
A non-woody plant stem is placed in water containing a red dye. It is left for one day and then a section of the stem is examined using a microscope.
Which tissue is stained red?
Did this page help you?
The diagram shows a cross-section through a leaf.
From which cell will most water evaporate during transpiration?
Did this page help you?
The graph shows daily carbon dioxide uptake and transpiration by the plant Agave americana.
The plant is adapted to live in very dry conditions.
What can be concluded from this graph?
More stomata are closed during dark periods.
More stomata are closed during light periods.
There is no carbon dioxide uptake during dark periods.
There is no water uptake during light periods
Did this page help you?
The diagram shows an onion plant that has been grown from a seed. Each onion plant takes two years to flower and produce more seeds.
What is the onion bulb acting as in stage 3 and in stage 6?
stage 3 | stage 6 | |
A | sink | sink |
B | sink | source |
C | source | sink |
D | source | source |
Did this page help you?