The trouble with discovery as a way of learning is that it takes many
years to get up to where we are now. I do a lot of my water relations
teaching in plant physiology in a rather Socratic manner, and the result
is that the students do wonderfully on that topic, but the rest of the
course is crowded because even the "leading question" type of discovery
takes a long time. But it's great for labs, as long as you have
something fairly straightforward in mind, especially the kind of
observational material from a century ago that Engelman's experiment
represents. Students still have to strain the brain to figure out what
it means. I'd love to get the Engleman experiment into our introductory
labs, both majors' and non -majors'.
What I'd like to see lots more of is the kind of thing that's in the
"Plantwatching" book (Wilkins), where the author replicates classic
experiments, then takes terrific pictures of them. In fact, short
presentations of experiments (even complicated to do, but not
complicated to understand) would be great: the question/hypothesis, the
experimental setup, the results...and have the students do some
interpreting. A lot of this could be done in the classroom, without
slowing things down too much. It's not as good as doing things "live,"
but there is a limit to the time students can spend in the lab.
In two years I will be working 50% time, and hope to start doing some of
this, producing short powerpoints that people can drop into the middle
of a lecture if they wish. In the mean time, for cheap thrills I have
been making some fancy animations of processes for my plant phys class.
Most of these will be much enlarged on next year, but if you have use
for them, you can download them in their early versions at
http://fp.uni.edu/berg/pp/download.htm
Note that they require PPT XP or later, or the free PPT 2003 viewer
(instructions on page above). They look like they are working in earlier
versions of PPT, but they ARE NOT WORKING RIGHT. I'm especially
interested in errors (there are some)--please report. Student feedback
on these is very positive.
--Gini Berg
Perry, Jim wrote:
>This would be really great to actually have the students DO, instead of
>telling them about the experiment. Discovery ... The best way of
>learning.
>>Jim Perry
>>>>>-----Original Message-----
>>From: owner-plant-ed at hgmp.mrc.ac.uk>>[mailto:owner-plant-ed at hgmp.mrc.ac.uk] On Behalf Of Kathleen Archer
>>Sent: Tuesday, May 04, 2004 8:20 AM
>>To: plant-ed at net.bio.net>>Subject: Engelman's experiment
>>>>>>Dear Plant Ed Folks,
>>I have been thinking about Engleman's famous experiment with
>>Spirogyra,
>>where he demonstrated the wavelengths of light that were used by
>>photosynthesis. He shined a spectrum of light onto the
>>filaments, and then
>>recorded where oxygen-seeking bacteria congregated due to
>>photosynthetic
>>oxygen production. Does anyone know what the bacteria were that he
>>used? The sources I've consulted so far don't identify them.
>>Kathleen Archer
>>>>******************************
>>Kathleen Archer
>>Dept. Biology
>>Trinity College
>>Hartford, CT 06106
>>Ph: (860)297-2226
>>kathleen.archer at mail.trincoll.edu>>*******************************
>>>>---
>>>>>>>---
>>>
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