This document outlines learning objectives related to transport in plants. It discusses the functions of xylem and phloem, their locations in plant structures, and the roles of root hairs in water and ion uptake. The pathway of water through roots, stems, and leaves is described. Transpiration is defined as the evaporation of water from mesophyll cells and its loss through stomata. The document explains how transpiration creates tension that draws water up plants and defines translocation as the movement of sucrose and amino acids in phloem to regions of storage, respiration or growth.
3. 5.1 Transport in plants5.1 Transport in plants
1. State the functions of xylem and phloem.
2. Identify the positions of xylem and phloem
tissues as seen in transverse sections of
unthickened, herbaceous, dicotyledonous roots,
stems and leaves.
4. 5.1 Transport in plants5.1 Transport in plants
3. Identify root hair cells, as seen under the light
microscope, and state their functions.
4. Relate the structure and functions of root hairs
to their surface area and to water and ion uptake.
5. 5.1 Transport in plants5.1 Transport in plants
5. State the pathway taken by water through root,
stem and leaf (root hair, root cortex cells, xylem,
mesophyll cells).
6. Investigate, using a suitable stain, the pathway
of water through the aboveground parts of a
plant.
6. 5.1 Transport in plants5.1 Transport in plants
7. Define transpiration as evaporation of water at
the surfaces of the mesophyll cells followed by
loss of water vapour from plant leaves, through
the stomata.
8. Describe how water vapour loss is related
to cell surfaces, air spaces and stomata.
7. 5.1 Transport in plants5.1 Transport in plants
9. Describe the effects of variation of
temperature, humidity and light intensity on
transpiration rate.
10. Explain the mechanism of water uptake and
movement in terms of transpiration producing a
tension (‘pull’) from above, creating a water
potential gradient in the xylem, drawing cohesive
water molecules up the plant.
8. 5.1 Transport in plants5.1 Transport in plants
11. Define translocation in terms of the movement
of sucrose and amino acids in phloem;
from regions of production to regions of storage
OR
to regions of utilisation in respiration or growth.
