B4.2.3.1

Plant tissues

Content

Students should be able to explain how the structure of root hair cells, xylem and phloem are adapted to their functions.

Students should be able to explain the effect of changing temperature, humidity, air movement and light intensity on the rate of transpiration.

Students should be able to understand and use simple compound measures such as the rate of transpiration.

Students should be able to:

  • translate information between graphical and numerical form
  • plot and draw appropriate graphs, selecting appropriate scales for axes
  • extract and interpret information from graphs, charts and tables.
  • The roots, stem and leaves form a plant organ system for transport of substances around the plant.
  1. Students should be able to describe the process of transpiration and translocation, including the structure and function of the stomata.
  2. Root hair cells are adapted for the efficient uptake of water by osmosis, and mineral ions by active transport.
  3. Xylem tissue transports water and mineral ions from the roots to the stems and leaves. It is composed of hollow tubes strengthened by lignin adapted for the transport of water in the transpiration stream.
  4. The role of stomata and guard cells are to control gas exchange and water loss.
  5. Phloem tissue transports dissolved sugars from the leaves to the rest of the plant for immediate use or storage. The movement of food molecules through phloem tissue is called translocation.
  6. Phloem is composed of tubes of elongated cells. Cell sap can move from one phloem cell to the next through pores in the end walls.
  7. Detailed structure of phloem tissue or the mechanism of transport is not required.

Use an appropriate number of significant figures,

Understand the principles of sampling as applied to scientific data,

Calculate areas of triangles and rectangles, surface areas and volumes of cubes,

Recognise and use expressions in decimal form,

Use ratios, fractions and percentages,

Construct and interpret frequency tables and diagrams, bar charts and histograms

, Translate information between graphical and numeric form,

Plot two variables from experimental or other data

Use of appropriate apparatus and techniques for the observation and measurement of biological changes and/or processes. ,

Safe and ethical use of living organisms (plants or animals) to measure physiological functions and responses to the environment (links to A-level AT h).,

Measurement of rates of reaction by a variety of methods including production of gas, uptake of water and colour change of indicator.,

Application of appropriate sampling techniques to investigate the distribution and abundance of organisms in an ecosystem via direct use in the field (links to A-level AT k).,

Use of appropriate apparatus, techniques and magnification, including microscopes, to make observations of biological specimens and produce labelled scientific drawings (links to A-level AT d and e).