Resources: Each group will need: eight small plants, two trays, labels, soluble fertiliser, ruler or string to measure and graph paper. Alternatively, this could be done as a whole class demonstration.
Handout: An investigation sheet for the students to complete.
Use the presentation from the previous lesson to recap on the placement and function of the xylem and phloem before going into more detail in the lesson.
Place a white flower in a tube of coloured water at the start of the lesson. Ask the students what they think will happen to the flower. Leave this for the remainder of the lesson and observe what happens at the end of the lesson.
Use the beginning of the presentation to recap on photosynthesis and a plant’s need for sunlight and water. Then, use the slides to discuss some of the minerals that are needed by plants for growth. Expand on the roles of the xylem and the phloem. Answer any questions during the presentation and then ask the students to set up their experiment (it will need to run for 2 weeks before collecting results and manipulating data).
Career Film: Dr Raghavendra Prasad works as a Postdoctoral Fellow at the RHS.
Expert Film: This is Dr Raghavendra Prasad, who works as a Postdoctoral Fellow at the RHS. Raghavendra talks about how plants gain minerals, nutrients and water.
For their task, the students will investigate the effect of fertiliser on plant growth.
Once complete, the students can plot their data in a graph to compare their results.
Support: Ask the students to look at a bottle of plant fertiliser and identify the elements in it (N, P, K). Then, ask them to use the internet to find out what these elements are needed for.
Challenge: Research key nutrients needed by plants and design a greenhouse set up that will provide everything needed to grow a prize-winning plant.
Use the assessment quizzes and keywords sheet to revise vocabulary and key learning from the unit.
Transportation of water, nutrients, minerals and food in plants is carried out by two different tissue systems. The xylem is responsible for the transport of water and minerals (a fluid commonly known as sap) from the roots to the rest of the plant. It is unidirectional (moving water and minerals away from the roots), predominantly made up of dead cells and provides stability to the plant. Water transported up to the leaves can also evaporate in a process called transpiration.
The phloem is responsible for the transport of food and amino acids from the leaves to the other parts of the plant, including the storage organs. This process is called translocation. The phloem is bidirectional and predominantly made up of living cells.
Roots are the part of a plant that are typically found below the soil. They are responsible for: (i) storing food reserves, (ii) anchoring the plant to the ground and (iii) collecting water and important minerals from the soil. Roots are usually covered in tiny hairs. This gives them a large surface area to speed up the rate of osmosis (i.e. the rate at which water and minerals are absorbed).