Transpiration

Figure 8 shows the lower epidermis of a leaf, with a stoma labelled.

(Source: © Quagga Media/Alamy Stock Photo)

Figure 8

State the number of guard cells shown in Figure 8.

State one gas that leaves the stomata and one gas that enters the stomata during daylight.

gas leaving stomata

gas entering stomata

State why the stomata close.

A student wanted to view the cross-section of a leaf on a prepared slide.

Describe how a light microscope would be used to observe this slide.

Sugars are transported from the leaves to the rest of the plant.

Explain how sugars are moved through the plant.

Figure 9 shows a root hair cell from a plant.

Name the part labelled X.

State one way that the structure of the root hair cell increases the volume of substances it absorbs.

Explain why root hair cells do not contain chloroplasts.

*(c) The arrows in Figure 11 show the direction of water movement through a tree.

Explain how water is moved from the soil, through the plant and into the air.

Figure 8 shows a diagram of a plant root hair cell.

Name the part labelled R.

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

Figure 9 shows xylem and phloem from the stem of a plant.

Living cells in phloem use energy to transport sucrose.

Which organelles release energy in living cells?

Describe two features of the structure of xylem vessels that can be seen in Figure 9.

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 10 shows the results of this investigation.

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

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

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 1 shows xylem and phloem from the stem of a plant.

Living cells in phloem use energy to transport sucrose.

Which organelles release energy in living cells?

Describe two features of the structure of xylem vessels that can be seen in Figure 1.

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 2 shows the results of this investigation.

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

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

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

(Source: © Maksym Holovinov/Shutterstock)

Figure 9

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 10 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.

Figure 1 shows an area of woodland with some small plants growing in the ground between the trees.

(Source: © Maksym Holovinov/Shutterstock)

Figure 1

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 2 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.

Figure 10 shows the leaves and flowers of water lily plants (Nymphaea odorata) on a lake.

Water lilies have stomata on the upper surface of the leaves.

Explain why water lilies have no stomata on the lower surface of the leaves.

The white petals of the water lily flowers cannot photosynthesise.

Which structure in leaf cells is the site of photosynthesis?

Glucose is made by photosynthesis.

Glucose is converted to another sugar to be transported in the plant.

What is the name of this sugar?

Describe how this sugar is transported from the leaves to the flowers of the water lily.

Figure 11 shows water lilies growing in a lake in Europe.

One water lily plant was brought from America 10 years ago and planted in the lake shown in Figure 11.

Explain why this non‑indigenous plant now covers the whole surface of the lake.

Explain how the water lilies will affect the biodiversity of this lake.

Figure 1 shows the leaves and flowers of water lily plants (Nymphaea odorata) on a lake.

Water lilies have stomata on the upper surface of the leaves.

Explain why water lilies have no stomata on the lower surface of the leaves.

The white petals of the water lily flowers cannot photosynthesise.

Which structure in leaf cells is the site of photosynthesis?

Glucose is made by photosynthesis.

Glucose is converted to another sugar to be transported in the plant.

What is the name of this sugar?

Describe how this sugar is transported from the leaves to the flowers of the water lily.

Figure 2 shows water lilies growing in a lake in Europe.

One water lily plant was brought from America 10 years ago and planted in the lake shown in Figure 2.

Explain why this non‑indigenous plant now covers the whole surface of the lake.

(a) (i) Water enters a plant through root hair cells.

Root hair cells have

Explain how water in the root is transported to the leaves of the plant.

How is sucrose transported from the leaves to other parts of the plant?

Figure 4 shows the average size of stomata in a leaf during one day.

Name the cells that change the size of stomata.

Describe the trend shown in Figure 4.

The temperature increased from 8 am to 1 pm.

Explain why this affected the size of the stomata.

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 13 shows this diagram.

State the number of stomata visible on Figure 13.

The student observed that the stomata were open.

Describe how stomata open.

*(c) Figure 14 shows xylem and phloem. Xylem and phloem are involved in the transport of substances through a plant.

Use Figure 14 to help you describe how water and sucrose move through a plant.

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 4 shows this diagram.

State the number of stomata visible on Figure 4.

The student observed that the stomata were open.

Describe how stomata open.

The leaf peel from the upper surface of this leaf showed no stomata.

Explain why it is an advantage to the plant to have this distribution of stomata in the upper and lower surfaces of the leaf.

(a) Figure 9 shows the effect of light intensity and temperature on the rate of photosynthesis.

Describe the effect of light intensity on the rate of photosynthesis.

Explain the effect of temperature on the rate of photosynthesis.

A student measured the rate of photosynthesis using algal balls in a laboratory. The tube of algal balls was kept at a temperature of 25 °C and was moved to different distances from a light source.

The results of this investigation showed that the rate of photosynthesis is

*(c) Explain how substances are moved through a plant by transpiration and translocation.