Translocation

Figure 12 shows the lower epidermis of a leaf, with a stoma labelled.

(Source: © Quagga Media/Alamy Stock Photo)

Figure 12

State the number of guard cells shown in Figure 12.

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 18 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 19 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 19.

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 2 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 3 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 3.

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 7 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 7.

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 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.

(a) Figure 16 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.