Plant Structure (Edexcel GCSE Combined Science: Biology): Exam Questions

Figure 1 shows part of a root as seen using a light microscope.

Figure 1

Figure 2 shows information about the two types of cells labelled in Figure 1.

Figure 2

(i) Calculate the surface area to volume ratio of the root hair cell. 

(2)

(ii) Explain how root hair cells are adapted for their function in the plant. 

(2)

Root hair cells can be viewed using an electron microscope. 

Describe and explain how the image in Figure 1 would appear different if taken using an electron microscope.

Xylem and phloem are both types of vessels that transport substances through plants. 

During periods of drought, xylem and phloem can experience shrinkage. This can be observed by measuring the circumference of the trunks of trees. 

Figure 1 shows the difference in circumference of three trees before and after a seven day period of drought.

Figure 1

(i) Calculate the percentage decrease in the trunk circumference of Handroanthus chrysanthus before and after the period of drought. 

(2)

(ii) Handroanthus chrysanthus had a larger leaf surface area than Podocarpus oleifolius. 

Suggest why this might have led to a greater decrease in trunk circumference in the Handroanthus chrysanthus.

(2)

Figure 2 shows the structure of a xylem and a phloem vessel. 

Figure 2

(i) Name two substances that are transported in xylem vessels. 

(2)

(ii) Describe the features of a xylem vessel that make it adapted for its function in the plant. 

(2)

Figure 1 shows how the leaves are arranged on a plant.

Figure 1

Which reason explains why the leaves are arranged in this way?

☐ A the upper leaves allow more light to reach the lower leaves

☐ B the leaves do not need stomata 

☐ C the phloem in the leaves will absorb more water

☐ D more insects will be attracted to the plant to eat the leaves

Figure 2 shows guard cells and stomata on the lower surface of a leaf.

A ruler has been overlayed on the image for scale purposes.

Figure 2

Use the ruler overlay to measure the length of the line on the labelled guard cell in mm.

The actual length of the labelled guard cell is 0.05 mm.

Calculate the magnification of this image.

Figure 3 shows the number of stomata per mm² on the lower surface of leaves from plants growing in soils with different water content.

Figure 3

Explain the difference in the number of stomata per mm² on the leaves of the plants grown in dry and wet soils.

Which statement from A to D would indicate that transport of materials in the phloem involves metabolic processes rather than just a physical process?.

Figure 1 shows an aphid feeding on a plant stem.

Figure 1

Explain why they target structure X.

Describe how the xylem is adapted for the transport of water.

Compare the transport systems in plants and animals.