1. Photosynthesis (1)
WALT: Describe two experiments that demonstrate photosynthesis

2. Last lesson, we learnt….. Nitrates are needed for
Nitrates are obtained from …………… by the ……………..
Nitrates can pollute rivers ……………..
Produce their own food through photosynthesis

3. LEAVES AND PHOTOSYNTHESIS

5. Leaves work in a similar way to the solar cell
Leaves work in a similar way to the solar cell. They both need a lot of light energy to work. Photosynthesis takes place in the chloroplasts inside the leaf cells.

6. Chloroplasts contain chlorophyll, a green pigment that takes in energy from the sunlight. All green parts of plants are able to photosynthesis because they contain chlorophyll.

8. Can you remember the word equation again?

9. Word equation for photosynthesis
carbon dioxide + water glucose light energy oxygen

10. released into atmosphere WATER from soil
LIGHT
from sun
GLUCOSE
for biomass and energy
CHLOROPHYLL
in the leaves
CARBON DIOXIDE
diffuses from the air
OXYGEN
released into atmosphere
WATER
from soil

11. The products of respiration are:
Oxygen
Glucose
Oxygen – released as gas into the air. Some is re-used as respiration.
Glucose – used for GROWTH (e.g. making cell walls or fruits)
- or stored as STARCH

12. There are two experiments that always come up in Common Entrance
There are two experiments that always come up in Common Entrance. We will look at one today.
Turn to page 70.
Take our leaves off the plant we semi-covered two days ago and carry out the experiment.
What safety considerations do we have (hint: use of ethanol)
Write down the steps you took in 5 points.
Write down a conclusion of what it proved.

13. What did this experiment prove?
Plants need light to photosynthesise
So glucose is only produced in parts of the leaves which had sunlight on them
This glucose was turned into starch

14. When you are finished…
Continue with the questions from yesterday in the KS3 books.