Rate of Photosynthesis All students can state what factors limit the rate of photosynthesis? - C Most students can explain how certain factors limit the rate of photosynthesis? - B Some students can use the law of limiting factors to enable farmers to increase crop yield? - A KEY WORDS Limiting factors Carbon dioxide Light intensity Temperature Illodea Starter Task! Can you recall the main layers of the leaf?

Starter: Who is the odd one and why? 1) Diffusion, active transport, osmosis Active transport- it requires energy, or diffusion because it does not require a membrane 2) Stomata, Palisade cell, root hair. Root hair cell-it is not part of a leaf 3) Glucose, oxygen, carbon dioxide. Carbon dioxide- it is not made in Photosynthesis. Glucose –it is not a gas 4) Oxygen, light, chlorophyll. Oxygen-it is not needed for photosynthesis 5) Temperature, Glucose, Carbon dioxide. Glucose-it does not limit the rate of photosynthesis

On mini whiteboards can you write symbol the equation for photosynthesis? Circle any factors that would limit the rate of photosynthesis

Solutions LO Checkpoint! All students can state what factors limit the rate of photosynthesis? - C Most students can explain how certain factors limit the rate of photosynthesis? - B Some students can use the law of limiting factors to enable farmers to increase crop yield? - A

3 limiting factors of photosynthesis 1.Light intensity 2.Carbon dioxide concentration 3.Temperature

Think! What is happening in this graph? Discuss in your pairs, then on your white board Describe what happens as the light intensity increases. Why does the graph level out? (think what might be a limiting factor?)

Lets become experts! Number 1’s form a group Number 2’s form a group Number 3’ s form a group Number 4’s fill the groups Each one of you have been given a graph to interpret. You will then feed back your interpretation to your original group.

Temperature Describe what happens as the temperature increases. Why? Explain what happens after 37 0 C

Light What does the graph tell you about light intensity? Explain this. What is most likely to be limiting the rate of photosynthesis at high light intensity?

Carbon dioxide What effect does increasing the concentration of CO 2 have on the rate of photosynthesis? Why? What could be limiting the rate at 0.13% CO 2 ?

A limiting factor is... When a process depends on two or more factors, for example photosynthesis. The rate of that process is limited by the factor which is in shortest supply So now in your groups can you come up with a definition for a limiting factor ?

Solutions LO Checkpoint! All students can state what factors limit the rate of photosynthesis? - C Most students can explain how certain factors limit the rate of photosynthesis? - B Some students can use the law of limiting factors to enable farmers to increase crop yield? - A

Putting it all Together Can your knowledge of limiting factors maximise plant growth?! Farmers can use their knowledge of these limiting factors to increase crop growth in greenhouses. What methods might they use to increase light? Increase the temperature? Increase carbon dioxide levels? What are the advantages to farmers of using these methods? Think about times of the day and year! Could farmers continually keep increasing the rate of photosynthesis? Or is there another limiting factor? Think about inside the plant!

Solutions LO Checkpoint! All students can state what factors limit the rate of photosynthesis? - C Most students can explain how certain factors limit the rate of photosynthesis? - B Some students can use the law of limiting factors to enable farmers to increase crop yield? - A

Homework Using the information on the sheet and your new knowledge of limiting factors. Either: 1) Design poster 2) Create a leaflet 3) Design an advertising campaign To explain to farmers how they could use greenhouses and knowledge of limiting factors to maximise their crop yield.

Plenary My other year 1O class have not done this lesson. On your sticky note write down three things that you think they should know before the lesson. Stick it on the board Three things you need to know about Limiting factors