We revised this topic today, which will definitely be in your exam in six weeks time. We also looked at the periodic table and separation methods.

lesson notes (and sats questions)

We can prove that chlorophyll (the green pigment) is needed for photosynthesis by using a geranium plant with variegated leaves (unfortunately we don’t have any). What would happen if we did an experiment on these leaves?

We put a plant in a bag with some pellets of sodium hydroxide. This removes carbon dioxide. We left the plant in the light and we will test for starch in two days.

notes/questions

 WE CUT OUT A SHAPE ON PIECE OF BLACK PAPER THEN STUCK IT TO A LEAF TO SEE IF A LIGHT IS NEEDED FOR PHOTOSYNTHESIS. WE WILL THEN TEST IT FOR STARCH IN TWO DAYS

ADAM/JESS

The point of the lesson was to find out how much starch was in a leaf.

We did this by killing the leaf in boiling hot water. Once we have done this we put it into enthanol in a boiling tube and then put that into the beaker with boiling water. This was so we could get rid of as much of the colour of the leaf. We then put iodine on the leaf and it went black, which showed it had made starch.

Adam (and kelly)