• Rearrange the cards into the correct order to explain the stages of photosynthesis…..
• Write out the photosynthesis equation in your books o prove your understanding and then help the others.

To be able to:
1. Describe what plants use glucose for (C)
2. Explain the test for starch in a leaf (B)
3. Explain why different plants store glucose as starch in different places (A/A*)

Uses of Glucose
• Describe what plants use glucose for (C)

• Describe what plants use glucose for (C)
For each of the 5 uses of glucose write at least a sentence for each use.
TA UP: To stretch yourself use the keywords and the textbook (p.20-21) to improve your answer.
Keywords
Synthesis, storage, respiration, cellulose, starch, chlorophyll, proteins, energy.

Expected answers
• Describe what plants use glucose for (C)
1. Glucose can be used for immediate energy release by synthesising ATP in respiration.
2. Glucose can be stored as starch grains and can be converted back into glucose when it is needed.
3. Glucose can be transformed into fats and oils, the carbon and hydrogen in the glucose molecule are used to synthesise fatty acids.
4. Glucose is used to make cellulose cell walls in plants.
5. Carbon and hydrogen can be combined with nitrates to make amino acids, these are then used to form polypeptides (or proteins) and eventually made into things like enzymes.

What is the problem?
• Describe what plants use glucose for (C)
• A farmer is trying to grow potatoes (which contain starch) but they are all really small everything else with the plant is fine.
• A flower shop owner is trying to grow
Sunflowers but the stems keep breaking but everything else is fine
Keywords
Synthesis, storage, respiration, cellulose
10 minutes to get down an answer to both problems.
Everybody writes.

Is chlorophyll needed for photosynthesis?
• Explain the test for starch in a leaf (B)
Chlorophyll cannot be removed from a plant without killing the plant.
Instead, variegated leaves can be used to show chlorophyll is essential for photosynthesis.
Variegated leaves have pale parts, which do not contain chlorophyll. The green parts of the leaf contain chlorophyll and are the control.
Which areas will react with iodine?
Only the green areas of the leaf react with the iodine and turn blueblack. Without chlorophyll, the pale areas have been unable to produce starch and do not turn blue/black colour

Match up the leaves with the growing conditions.
• Explain the test for starch in a leaf (B)
TA DOWN:
Extra clue 1: soda lime removes carbon dioxide
.
Extra clue 2: hydrogen carbonate adds carbon dioxide .

ISA Prep: Evaluate the method.
• Explain the test for starch in a leaf (B/A)
• Look at the method you have been given. You may annotate it
15 min
1. Can you suggest a hypothesis for this experiment? a) If not why not?
2. Suggest a reason why this a good or bad method method?
3. Explain the improvements we would need to make to this method (think testable hypothesis).
Stick the method into your books, you will need it for revision.

• Explain why different plants store glucose as starch in different places (A/A*)
• Look back at your statements about what plants use glucose for.
• Try to use them to explain why plants store glucose as starch in different places.
– Hint: think about active transport, where it happens and the reasons for requirements of glucose.

Photosynthesis – Test yourself
• Review the outcomes by answering the test yourself questions.
• Once finished self assess using the mark scheme.