Xylem and phloem

Plants produce glucose by photosynthesis.

Complete the word equation for photosynthesis shown in Figure 2.

Figure 2

State why photosynthesis does not occur in the roots of plants.

Which is transported in the phloem?

Chlorophyll is found in green leaf cells.

Describe the role of chlorophyll in leaf cells.

A greenhouse contained an oil burning heater.

State two ways this could increase the rate of photosynthesis in the greenhouse.

8 (a) Figure 14 shows a diagram of a plant root hair cell.

Figure 14

(i) Name the part labelled R.

(ii) Explain one adaptation of a root hair cell that increases the absorption of water and mineral ions.

(b) Figure 15 shows xylem and phloem from the stem of a plant.

Figure 15

(i) Living cells in phloem use energy to transport sucrose. Which organelles release energy in living cells?

(ii) Describe two features of the structure of xylem vessels that can be seen in Figure 15.

(c) A scientist investigated how the flow of air affected the rate of transpiration in a plant. A fan was used to change the flow of air. The volume of water taken up by the plant was measured. Figure 16 shows the results of this investigation. fan switched on

time in minutes

Figure 16

(i) Explain why switching on the fan caused a change in the volume of water taken up by the plant.

(ii) Give one reason why the volume of water taken up by the plant was also measured when the fan was not switched on.

(iii) Calculate the rate of water uptake from 8 minutes to 10 minutes when the fan was switched on. Use the equation

_{..............................................................}mm³ per minute

2 (a) Figure 2 shows xylem and phloem from the stem of a plant.

(i) Living cells in phloem use energy to transport sucrose. Which organelles release energy in living cells?

(ii) Describe two features of the structure of xylem vessels that can be seen in Figure 2.

(b) A scientist investigated how the flow of air affected the rate of transpiration in a plant. A fan was used to change the flow of air. The volume of water taken up by the plant was measured. Figure 3 shows the results of this investigation. fan switched on

time in minutes

Figure 3

(i) Explain why switching on the fan caused a change in the volume of water taken up by the plant.

(ii) Give one reason why the volume of water taken up by the plant was also measured when the fan was not switched on.

(iii) Calculate the rate of water uptake from 8 minutes to 10 minutes when the fan was switched on. Use the equation

_{..............................................................}mm³ per minute

Figure 16 shows an area of woodland with some small plants growing in the ground between the trees.

(Source: © Maksym Holovinov/Shutterstock)

Figure 16

The leaves of the small plants are green.

Describe how these plants make glucose.

Name a group of organisms that break down the dead leaves and release mineral ions into the soil.

The mineral ions are absorbed from the soil into the roots of plants.

Describe how these mineral ions are transported from the roots to the leaves of the plants.

A scientist recorded the mean light intensity and the mean number of small plants per m² for six 25 m² areas of the woodland.

Figure 17 shows the results.

Explain the effect of light intensity on the number of small plants per m².

State one variable the scientist should have controlled to make sure the light intensity measurements could be compared.

The scientist selects an area near the edge of the woodland where many stinging nettles are growing.

This area is partly shaded by the trees.

Describe how the scientist should use a belt transect to investigate how light intensity affects the growth of stinging nettles.

State why a coverslip is placed on top of the leaf peel.

Explain why the leaf peel rather than the whole leaf was viewed with a microscope.

The student drew a biological diagram of the leaf peel taken from the underside of the leaf.

Figure 23 shows this diagram.

State the number of stomata visible on Figure 23.

The student observed that the stomata were open.

Describe how stomata open.

*(c) Figure 24 shows xylem and phloem. Xylem and phloem are involved in the transport of substances through a plant.

Use Figure 24 to help you describe how water and sucrose move through a plant.