Australia's Science Forum

We usually do the phenolphthalein agar surface area to volume prac with our year 12 biology classes, but last year they decided to do it with the year 11s, so our HOD doesn't want to repeat it with them again now they're in year 12. Didn't see that coming huh?
Now we need to find a different prac demonstrating the concept.......

Does anyone have a good alternative using potato or something else?

Cheers,

You're on the right track
Using cubes of potato and crushing one then adding Hydrogen peroxide but this is a differant Dot Point demonstrating reaction rate!

If you look up

http://www.teachersdomain.org/resource/ ... ellreplic/

you will find a prac using balloons. It says grades 6-8 but it will still give a simple explanation.

there is links to video on mitosis and single cell organisms (I think)

good luck
Rita

I found a prac using potato at the following link

http://www.docstoc.com/docs/34666880/Su ... Volume-Lab

It may be what you're after!

Robyn