Monday, January 29, 2007

Magic Bubbles

This beaker of pond scum sits on a sunny window sill in my lab. It's leftovers from a pondwater microscope lab that we completed before Christmas.
When the sun blasts through the south facing window adjacent to the beaker, the scum revs it's photosynthetic engine and streams of bubbles flow upward.
I keep it there for the kids. It's one thing to hear me drone on about glucose production, balancing the photosynthesis equation, and how the oxygen produced is just a by product. I like to tell the knuckleheads, " Suppose your friend had built a car out of 36 Leggo blocks, then passed the car to you. You disassembled his Leggo car and built a boat out of 24 of those blocks. The boat was perfect and you had no use for the extra 12 leggos. They were simply leftovers."
THAT'S the oxygen produced in photosynthesis."
It's quite another thing to peer into a sunlit Pyrex beaker and see life sustaining oxygen literally pouring from something as simple as some green pond scum.
Now, I need to head to work. My pond scum has been alone all weekend and it misses me.
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16 comments:

pablo said...

Are you teaching graduate students now? What's with the complex and difficult analogies to colorful plastic blocks?

pissed off patricia said...

When pond scum misses you, you know you have a friend indeed. :)

I'm with the pond scum liberation society. You must release the pond scum back into its natural habitat. Do it now! Don't make me come up there.

I'm not sure where in Fla you are but I can tell you it's cold here on the southeast coast this morning. Tonight we may have freeze warnings here. We're having winter in dribs and drabs this year. By Thurs it'll be back in the low 80's. If your pond scum were down here, you might need to toss it a blanket tonight.

robin andrea said...

What a great way to teach, fc. The Leggo analogy is very good, but pond scum producing oxygen right there in the south-facing window, that's a lesson hard to miss. Well done.

Thunder Dave said...

fairly similar to carbon dioxide (CO2)the fermentation process!

thingfish23 said...

I thought that was a photo of a developer. But it was pond scum. It's hard to tell the difference.

kathy a said...

"pond scum" is the term my sisters and i have always used to describe unspeakably yucky people or ideas.

we are city girls, but i really blame our high school biology teacher -- we all had the same teacher, although we cover an 8 year range in ages.

every so often the bio class would do a dissection [although one sister got out of doing the frog segment personally by saying, "ICK! no way!"], but the major scientific activity in her class was seeing how fast we could get her distracted. ["30 seconds, a new record! let's see if we can get her to bring out the candy jar now."]

anyway, any accidental biological information we picked up was largely due to other factors, such as reading something interesting, cramming for the AP biology test, marrying scientific types, going to science museums with our kids, etc.

this is a very cool classroom display! i love the lego example, too. (my husband is right there with dave on the wonders of beverage transformation via biological processes.)

vicki said...

Laughing at Pablo. I like your pond scum. Reminds my of this completely closed glass ball that Abby gave me 4 years ago with 3 tiny brine shrimp and a bit of algae in the water. They all just keep swimming around and around. I know it's not the same- I'm just saying it reminded me of that.

I didn't even respond to your last post when I saw it yesterday. Jealousy and envy over not having a state shell more than 4 months a year just tipped me over to a point where there were no words.

Floridacracker said...

Pablo,
You have to make it real for them :)

POP,
Some say it's natural habitat is inside the beltway...
Think Cedar Key area and yes we are going to drop to 22 tonight ... for hours.

Robin,
Those scum were at it all day today. Crazy little producers.

ThunderD,
You would think of that!

Thingfish,
It was an honest mistake.

Kathy A,
I can usually sense when obfuscation attempts are afoot. I like to go with it just a little, guiding and nudging, and then SURPRISE! ... I show them the connection with our main topic.
It takes some practice :)

Vicki,
I've seen those enviroball thingies.
Sorry about the lapse in stateshelliness. Illinois ...hmmmm ... Maybe the zebra mussel?
(ducking now ...)

Laura said...

I have to agree with Thingfish... his comment rings so true. I see the CEO's of our insurance companies in there as well. Forgive me if I pour in some bleach...

Floridacracker said...

Laura,
Those guys give pond scum a bad name.

Deb said...

Yay thingfish! And I agree with Thunder Dave, nothing like the sound of CO2 bubbling thru an airlock, evidence of fermentation.

Hurricane Teen said...

FC, you asked me about a week ago whether I knew Bootie Pacetti. Well...
If we're talking about the same person (there's not a lot of Bootie's out there :-D), I know her quite well. She is Mr. Stuart Pacetti's mother. She's quite old...93 I believe...but she sure gets around! She was also a nurse at my mother's birth and her signature is on my mom's birth certificate. So there ya go. Small world, eh?

Floridacracker said...

Deb,
Seems to be some fermentation fans around here.

HTeen,
That's her. My Mom knows her and my folks know Stuart.

kathy a said...

i have no idea who bootie is, but isn't it wonderful when we stumble across connections in this big world?

that happens all the time in the south, where everyone's people know everyone else's people, somehow or another. that's one of the reasons i liked living in south carolina, back when. as a californian, though, it still amazes me.

our big family discovery this week was that daughter's saxophone teacher and one of my sisters were at the same Big Game in 1982 [cal vs. stanford], albeit on enemy sides. long story short, after the orchestra concert this weekend, both teacher and sister circulated the exact same photo of the highlight of the event, within minutes of each other -- it was a photo of very young sax teacher running like hell to get out of the end zone [where the band had confidently assembled] so he didn't get run over by an enemy football player twice his size. this is what passes as "small world" out here. LOL

swamp4me said...

Ohhh, I do love a beaker of left-over pond water. It's always full of the most amazing things. I'm pretty sure there are swamp monster eggs in there somewhere.

Floridacracker said...

Kathy A,
Whoa, what are the odds of that happening?
HTeen and I don't know each other, but we are both branches of an old St. Augustine tree.
He's the young branch ...

Swampy,
I shall nourish it and hope ;)