Digesting Sunshine - How Mother Nature Turns Light Into Chemical Energy

Howdy, Science Fans!

I've been on hiatus from BTDS, but I'm back, and gearing up for some new programs soon. More about that later. First order of business - the last few programs in 2012 never got write-ups, so I'm posting them now!

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In February 2012 our speaker was Dr. Rob Burnap from the Department of Microbiology at OSU. Dr. Burnap is trying to work out a very important and very difficult puzzle - how exactly do plants accomplish photosynthesis?

Photosynthesis is that trick we all know plants like to do. They turn carbon dioxide, water and sunshine into oxygen (good for us!) and chemical energy that they use to grow.

This is an important trick to understand. Part of the process involves splitting water molecules into hydrogen and oxygen. If we knew how to do that as efficiently as plants, we'd have have our energy problems solved! That's because the reverse process, putting oxygen and hydrogen together to form water, releases a lot of energy quickly.

We CAN split water using a process called electrolysis. Dr. Burnap brought a special electrolysis set-up that allowed us to see (using a ph indicator that changed colors) how it works. We connected electrodes to a battery, put them in the water, and watched the bubbles of hydrogen forming on one end and oxygen on the other.

We used a nine volt battery to supply the power needed to pull those water molecules apart, and the bubbles came out pretty slowly. A plant could do the same thing with just one volt's worth of sunshine! We tried using a one volt battery, but nothing happened.

Electrolysis in action!

Unfortunately electrolysis uses up way more energy than you can ever get back by burning the hydrogen it releases. But if we knew exactly how plants use sunlight to split water, maybe we could do it that way. Then it wouldn't cost much at all to produce lots of hydrogen (or possibly hydrocarbons, similar to gasoline).

At this point in the program, I shared the song I wrote, inspired by Dr. Burnap's research. It's called "Photosynthesis Machine."

You've probably heard of chloroplasts and chlorophyll. Chloroplasts are the structures inside plant cells where photosynthesis happens, and chlorophyll is the chemical in the chloroplasts that makes plants look green and allows photosynthesis to happen.

Dr. Burnap uses green algae in the lab as a stand-in for plants. Its photosynthesis machine is pretty much the same, but the algae is easier to work with.

But if you're like me you probably never realized that chlorophyll doesn't do the job alone. Dr. Burnap studies the protein structure that contains the chlorophyll. It's called the "reaction center," and it's a molecular machine that brings all the ingredients for photosynthesis together, recombines them, and moves the resulting products apart.

It's a photosynthesis machine!

 

That blobby shape on the screen behind Dr. Burnap is a computer model of part of the reaction site.

How exactly does the photosynthesis machine work? We know a lot about it already, but there are still many details to figure out. The challenge is: how do you study a machine so small you can't even see it with a microscope?

One way Dr. Burnap studies the molecular machine is by measuring how fast it works, then messing with it to see if he can slow it down. He uses a strobe light and an oxygen detector as a speedometer. The light flashes; the plant makes oxygen; the detector measures how much and how fast. We're talking super-fast speeds here. The video below shows how quickly the strobe light flashes on and off.

Some questions Dr. Burnap was working on were: Why don't the hydrogen and oxygen just bond back together right after the photosynthesis machine pulls them apart? How exactly does the photosynthesis machine move hydrogen away from the reaction site so that doesn't happen?

To slow down the machine, Dr. Burnap gave his algae heavy water instead of regular water. Heavy water is made with deuterium instead of hydrogen. Deuterium is a hydrogen isotope, containing one proton AND one neutron, so it weighs about twice as much as regular hydrogen. Heavier things are harder to move, so...

Would the machine have a harder time moving these heavy hydrogens out of the way? If so, would that also slow down the rate the oxygen gets released? It turns out: yes, and yes!

We made a human photosynthesis machine, using balloons to represent hydrogens and oxygens.

Dr. Burnap suspects that certain parts of the photosynthesis machine act like a bucket brigade. A series of proteins pass each hydrogen atom down the line in order to move it out of the way once it's been freed. One way to test this hypothesis is to change the machine and see what happens. Dr. Burnap was able to grow a special algae by "knocking out" one of the proteins in the bucket brigade. With this protein missing, would the hydrogen pile up? Would that slow down or stop the photosynthesis process?

Next we put our bucket brigade behind the screen, since Dr. Burnap can't see directly what's happening in real life either, and we took one of the proteins (people) out. Did the hydrogens (black balloons) still make it across to the other side? Surprise surprise - they did! How did they do that?

Using the strobe light and oxygen detector speedometer, Dr. Burnap discovered that even with one of the proteins missing, the machine worked just fine! This suggested to him that the proteins are not arranged in a straight line, but are interconnected so that the hydrogen has more than one path out.

We had a blast during the program re-creating Dr. Burnap's bucket-brigade experiment with people standing in for proteins and balloons representing hydrogen and oxygen molecules!

It's pretty amazing what we can figure out about how a machine is put together, even if it's too small to observe directly! If we keep piecing together details, one day maybe we'll be able to build our own photosynthesis machines to convert sunlight into chemical energy that we can use!

Playing with the electrolysis after the program.

Me on the left, Dr. Burnap on the right.

Fungus Among Us! Saturday May 19!

Yes, our last scheduled Born to Do Science is tomorrow!!

May 19, 2012

The Fungus Among Us!

When Fungi Attack, Science Fights Back

Stephen M. Marek PhD from the Department of Entomology and Plant Pathology at Oklahoma State University will speak about his use of molecular tools to investigate "who done it" and how to stop it when important crops suffer damage from pathogenic fungi.

We will have microscopes on hand with lots of fungi to observe!

10:00 AM at the Stillwater Public Library. I hope to see you there!

Predators and Prey this Saturday!

Yes, we are having a Born to Do Science tomorrow!!

April 21, 2012

Predators, Prey, and the Games They Play!

Computer Models Reflect Real-World Animal Behavior

Dr. Barney Luttbeg from the Oklahoma State University Department of Zoology will speak about his research using tadpoles, dragonfly larvae, and computer simulations to understand the complex interactions between predators and their prey.  

If you can, please bring a chess board, chess pieces (or any game pieces you like), checkers (or any flat tokens with two colors), and a coin to flip or dice to role.

We will also have live tadpoles and dragonfly nymphs to observe!

New Music Video - Science Frontier!

I'll get caught up soon with photos from the last to BTDS events. In the meantime, please enjoy this brand new video for my song "Science Frontier!" Many thanks to Brian Collins, who wrote, produced, and directed it!!

This Saturday - My One and Only Vole!

Don't forget we're meeting a week early this month! Saturday March 10. I hope to see you there! We're working on setting up a live vole-cam in the lab! Here's what the program is about:

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Vole pups! I borrowed this photo from a Mother Nature
Network article, 11 Animals that Mate For Life.

Zoology student Tomica Blocker will share the science of "voles in love" in a program for children Saturday at the Stillwater Public Library.

Blocker, a master's student in zoology at Oklahoma State University, will present "My One and Only Vole" at Monty Harper's "Born to Do Science." "Born to Do Science" is a monthly program that gives students a chance to meet scientists and learn about their research. The series is hosted by Monty Harper, a local children's musician who composes a song for each program inspired by his guest scientist's work.

Three brother voles moved nesting material
one mouthful at a time from one end of
their tub to the other while I interviewed
Tomica about her research.

"Prairie voles are a fascinating species to study," said Harper. "It's a rare mammal that sticks with a single mate for life. It's even rarer to find a mammal species where mothers and fathers both care for their young. That's why certain types of prairie voles are useful model species for investigating human behavior and physiology; they are rodents with family values. We can learn a lot about ourselves by studying these cute little monogamous mammals."

The presentation will include hands-on activities for the participants. "This one will be a lot of fun," said Harper. "We'll have kids up acting out vole social recognition using olfactory cues, analyzing vole behaviors in videos from the lab, and even designing their own vole research!"

One of the voles gets a sunflower seed treat.

"Born to Do Science" is free and open to students in at least third grade. Parents are encouraged to attend, participate, and learn along with their children. It will begin at 10:00 a.m. in Room 119 of the library. Registration is requested at (405) 377-3633 or askalibrarian@stillwater.org.

For more information about "Born to Do Science" or to listen to podcast interviews with past guest scientists, visit www.BornToDoScience.com. Stillwater Public Library is at 1107 S. Duck St.

BTDS Podcast Episode 3: "Stargazer"

This is a double-wide episode with two NASA astrobiologists! Kid host Aaron and I speak with Dr. Nader Haghighipour about his work finding extrasolar planets (including Gliese 581 c!) and we speak with Dr. Vikki Meadows about how we might detect signs of life on extrasolar planets. Featuring a new song, "Stargazer"!

Listen / Download the Podcast

Subscribe on iTunes

Aaron's World!
My co-host this week is Aaron from Aaron's World, a fantastic science podcast for kids which I highly recommend you check out now! The "Stargazer" song is also featured in Aaron's World episode 28, "Plesiadapis."


Feedback, please! 
Please post comments below or write to btds at montyharper.com - What worked for you? What didn't?
I will incorporate your feedback as I tweak the format over the next few episodes.

Also, please post your questions about the science!! They will be answered!

Get the song:

Digesting Sunshine

This Saturday morning at 10:00am, Born to Do Science presents... Dr. Rob Burnap, a microbiologist at Oklahoma State University, who will share with us his research on photosynthesis.

So you think you know photosynthesis? We all learn about it in grade school, right? It's easy to get the impression that photosynthesis is all figured out. If that's the case, why aren't we efficiently using the sun's energy to run our world, just like plants do? It turns out there's a lot more to know and Dr. Burnap is one of the many scientists around the world who research this important topic!

We are planning wall-to-wall demonstrations and activities on Saturday to help you understand why photosynthesis is so complex, amazing, and tough to untangle. Please join us at the Stillwater Public Library! The program is designed for kids in 3rd-7th grade and their adults to enjoy together. See you there!!

Photos from the lab:

Green algae are a convenient species to use to study photosynthesis. It is also hoped that we can eventually use algae to produce clean fuel for transportation on a commercial scale.

This equipment measures the Oxygen output from photosynthesis to an incredible degree of accuracy. Such data can be used to better understand how photosynthesis works.

Here is Dr. Burnap, looking a bit green. He often has to work under green lighting in the lab. Can you think why that would be? Be sure and ask on Saturday!

BTDS Podcast Episode 2: "It's Not Fair"

Dr. Jennifer Byrd-Craven shares her research into whether teenagers who co-ruminate increase their stress, with kid host Evalyn, featuring the song "It's Not Fair (When Your Mother is a Scientist)."

Listen / Download the Podcast

Subscribe on iTunes

Feedback, please! 
Please post comments below or write to btds at montyharper.com - What worked for you? What didn't?
I will incorporate your feedback as I tweak the format over the next few episodes.

Also, please post your questions about the science!! They will be answered!

Get the song:

Left Brain, Meet the Right Brain!

Our first program of the new year was Dr. Shelia Kennison, "This is Your Brain on Words!"

If you really think about it, it's an amazing thing that we can get lost in a book the way we humans often do. I mean, look at a page and what do you see? Black squiggles on a white background. Somehow we turn those squiggles into words and those words into sentences and those sentences into stories that envelop us like waking dreams. What exactly are our brains doing to make that happen?

I performed a new song called "Left Brain" in which Left Brian thinks he can read on his own but in the end he has to admit that Right Brain helps. 

Lisa and Evalyn joined me on the stage for the ending which involves three overlapping musical parts for the left brain, right brain, and corpus callosum. Thanks to Dr. Kennison for sending this photo!!

If brain scanners were faster, we might be able to just watch a person's brain light up as they read. But we decode words way too quickly for any current brain scanning technology to record the process. Dr. Kennison uses an ingenious method that brings us baby-steps closer to understanding what goes on inside when we read. She peeks into the workings of our brains - with grammar. 

When we see a singular noun that might not make sense in a sentence, this doesn't bother us much because singular nouns are often used as adjectives. 

For example, "Sally married the computer..." might not seem so weird once you read the entire sentence: "Sally married the computer repairman."

However, if we make the noun a plural, that's different!

"Sally married the computers..."

There's really no way to finish that sentence so that it makes good sense. 

Dr. Kennison investigates whether these types of grammar glitches can tell us anything about how the brain is working, and she has uncovered some very intriguing patterns.

Dr. Kennison

To understand what Dr. Kennison discovered we need to know about the corpus callosum. This is the part of the brain that connects the left and right sides together. It's the only pathway by which the left side of the brain can "talk to" the right side, and visa versa. 

Just like an internet connection has a particular data transfer rate (or speed), so does a corpus callosum. We call that speed the interhemispheric transfer time, or IHTT. We can measure a person's IHTT at a given moment by having them respond to flashes on a computer screen.

Here our first volunteer measures the speed of his corpus callosum.

For a long time we've known that various different language functions are handled by the left brain. However over the past ten years or so the role of the right brain in language has become more apparent. Dr. Kennison believes that the two halves of our brains are probably always working together to decode language.

She gave her subjects a whole bunch of sentences to read. Some of them had trick plural nouns in them that didn't make sense. Others had weird singular nouns. Others were just regular sentences. She measured if and when each reader slowed down, and by how much. (We're talking about milliseconds here - very small differences in time!)

Here our second volunteer measures his reading speed. He was a quick - I couldn't keep up!

This is what the reading software looks like (projected on our screen). We only get to see one or two words at a time as we move through a sentence. This way the computer can measure our reading speed at each word, and can tell exactly where we might slow down. The software is less detailed than tracking eye movements, but much easier, and gives essentially the same results for the purpose of this experiment.

Then Dr. Kennison measured each of her subject's interhemispheric transfer time. Remember, that's the speed of their corpus collasum. And guess what she found?

The speed of a person's corpus callosum corresponds to the amount they slowed down when reading weird singular nouns. 

What this might suggest is that when we come to an unexpected singular noun in a sentence, the left brain consults with the right brain (via the corpus callosum) to try to make meaning out of the strange word combination. Maybe the right brain is telling the left brain to go ahead and consider the next word because this unexpected noun might make sense as an adjective.

Of course as with any new study, the results are tentative. Dr. Kennison plans to run many more experiments to see if she will continue to observe this interesting effect! And hopefully many more similar experiments will help us better understand how we make meaning out of all those squiggles on a page!

Brain Science This Saturday!!

Howdy, Science Fans!

Our next BTDS program is about studying the brain! How does your brain work?? You might know that it's separated into two halves - the left brain and the right brain, and that the two halves generally specialize in different types of thinking. The two halves are connected by a thick cord of neurons called the corpus callosum.

Most of what we know about which half does what we've figured out from brains that aren't functioning normally. For example if a person's brain is injured and they lose the ability to speak, then we know that the part of the brain that was injured must have something to do with speaking. Studies on people whose corpa callosa has been severed (for other reasons) can tell us a lot about how the left brain functions without the right and how the right brain functions without the left.

But it's a lot harder to find out anything about how the brain works when it's whole and healthy and functioning properly. We can't just watch it do its thing! How and when and why do the two halves "talk" to one another? What does each half contribute when they are working properly together?

Our guest scientist this month has an ingenious way of studying these aspects of our brains!

Dr. Shelia Kennison is a psychologist who uses glitches in language as windows into how our brains function. By carefully studying how people make meaning out of written words, she can reveal communication between the two sides of the brain!

We will get to experience what it's like to be one of Dr. Kennison's subjects, and as always we'll get to "think like a scientist" and explore other ways the mysterious workings of the brain might be understood.

The program starts Saturday morning at 10:00 at the Stillwater Public Library, room 119.
I hope to see you there!!


In the meantime, check out these related websites!

- For a quick overview of left and right brain functions check out this chart from funderstanding.com

- The Split Brian Game - you become a researcher studying "Mr. Split Brainy." See if you can figure out what's going on in his head!

- To find out how left or right brained you are, take this test!

Here are my results - please post yours!

Thank you for taking the Creativity Test. The results show your brain dominance as being: 

Left Brain	Right Brain
53%	47%