A researcher treated a 1 cm section of a plant stem. The treatment killed all living cells in that section but did not damage the cell walls.

The researcher made measurements under the same environmental conditions before and immediately after the treatment.

Measurement	Before treatment	After treatment
Volume of water moved from the roots to the leaves in 1 hour	3.2 cm³	3.1 cm³
Mass of dissolved sugar moved from a leaf above the treated section to the roots in 1 hour	0.80 mg	0.05 mg

Use differences in the structure and function of xylem and phloem to explain both results in the table.

The plant later uses dissolved sugars stored in its roots for growth in a shoot above the treated section.

Suggest how the treatment would affect the movement of these sugars to the shoot. Explain your answer.

A researcher treated a 1 cm section of a plant stem. The treatment killed all living cells in that section but did not damage the cell walls.

The researcher made measurements under the same environmental conditions before and immediately after the treatment.

Measurement	Before treatment	After treatment
Volume of water moved from the roots to the leaves in 1 hour	3.2 cm³	3.1 cm³
Mass of dissolved sugar moved from a leaf above the treated section to the roots in 1 hour	0.80 mg	0.05 mg

Use differences in the structure and function of xylem and phloem to explain both results in the table.

The plant later uses dissolved sugars stored in its roots for growth in a shoot above the treated section.

Suggest how the treatment would affect the movement of these sugars to the shoot. Explain your answer.

2.3 Plant tissues, organs and systems

2.3 Plant tissues, organs and systems Questions