Photosynthesis Elodea /

Normal variegated leaf de starch(leaf left in dark for 2/3 days)                                                     Beacky use Waterbath + boiling tubes holder (dish                                                                                                                                                                                  washer   basket) in water bath, tong 

hibiscus leaf for varigated starch test

To be made the day before

testing a leaf for starch

• 2 X Water Bath @ 100 /kettle (boiling leaves and boiling tubes)/ gas and beakers ... if water bath add "dish washer" basket to hold boiling tube, tong to pick them up

• Normal (Basil or geranium) and De-starch plant variegated under light for 48h  and normal in the dark  for 48h 

• 250 cc breaker (to boiled leaf) (No if water bath are used)

• Iodine in dropping bottle

• Ethanol in dropping bottle

• Blue plastic Tweezers and/or test tube holder (inclass)

• Petri-dishes,

• Glass rod

• Pens

• boiling tubes 

• Timers

O2 Production photosynthesis :

• Pond weed

• Lamps

• Ruler meter

• Beakers

• Paper clips/ blue tack (to act as a weight if needed)

• Boiling tubes

• Colour filters

• Elastic bands

• Timers

Tips for planning and preparation 

• Most species are available all year round from aquarium suppliers, however, try to do the practicals in summer and autumn when pond-weeds are most active and produce the most bubbles 

• Purchase 2-3 different types and test them out beforehand because the activity can vary greatly 

• To prevent cold shocking the plants, and to allow any chlorine to diffuse out, prepare a tank of tap water 24 hours before adding the pond-weed 

• Aerate the tank gently with an aquarium pump and illuminate with a lamp of around 1000 lumens in preparation for experimentation Tips for the practicals 

• Put 0.4%-1% sodium hydrogen carbonate solution into your chosen practical container, generally a boiling tube, possibly a beaker. Pond-weed does not thrive in concentrations above 1% 

• Insert the stem upside-down into the boiling tube and cut the stem underwater at an angle

• If the stem fails to bubble there could be an air lock. Re-cutting the stem can occasionally solve this, or try cutting the stem in a different place

• Use a lamp with at least 1000 lumens 

to try from Blade biology : Myriophyllm scabratum (LBA 042) - Ergeria densa (LBA 030)