Spaceward Bound Teacher Blog Tuesday 22 March 2011

Matthew Reyes: Recap: Today’s experiments consisted of testing for life in soil crusts, extraction of chlorophyll from soil, and creation of a mud battery.

In testing for life in soil crusts we prepared three sets of solutions as follows:

Crust+ Indigo Carmine Blue (Dye)+ LB media
Pavement+ Dye+ LB media
Sand+ Dye+ LB media
Crust + Dye
Pavement + Dye
Sand+Dye
AND one Control of: Dye+ LB media

Crust refers to the soil samples we collected that contained biological crusts, pavement refers to soil samples collected in the same area that did not contain any visible life, and sand refers to a sample collected from the Kelso sand dunes.

The experiment was set up in nine test tubes. Every two hours we are measuring absorption using a spectrophotometer. The test for life uses a color changing redox reaction between the dye and sugars found in the solution. No color change has been noticed yet, but the solutions will continue to incubate over night and more accurate observations will be made later.

Chlorophyll extraction posed the question: “What type of chlorophyll do biological soil crusts contain?” The process of extraction used 3mL ethanol with 1.5g crust. It was placed in the oven at 70 Celsius for 5 minutes. It was then placed in mixing until cool for 45 minutes. UV/Vis scan measured between 240-800nm. The resulting spectrum results suggested the presence of mixture of chlorophyll A, chlorophyll B and possibly -carotine.

The mud battery will be used in the oasis lake on the Zzyzx property. Its components include a mat of 3000 micro threads bulks of carbon fibers. Each bulk of thread was then weaved with copper wire. One long piece will be put in the water under the ground of the lake in order for cyanobacteria to grow. Another piece of carbon fibers weaved with copper wire will be put above the ground which will be a conductor of energy. Four long thick pieces of graphite are then partially insulated with copper. This will serve as another conductor out of the water and into the battery. There is also a switch which we fabricated in order to control amount of resistance and to turn circuits on and off. The battery will act as a prototype for a possible battery source deep in the ocean to power deep ocean probes where there are no other possible energy sources (i.e. geothermal vents, currents, or sunlight) available to run the probes on.

Tonight’s presentation was titled, Scotch on the Rocks, by Keith Evan Schubert, Jane and Ernesto. Biological soil crusts are colonies of different organisms cooperating together to survive in their environment. In order for these organisms to survive successfully in their environment, they often grow in distinct patterns. These patterns are often the same linear or circular patterns; a pattern of life as it forms groups in an environment. The formation of these patterned designs can be very intricate. The shape of these microbial communities can potentially reveal information about what environmental factors are most important to life in their ecosystem.

Complex mathematical models have been developed in the attempts to explain the patterns of growth given certain biological parameters. The limitation of these models is that they are impractical for field use since the parameters are difficult to alter. A simpler, binary system of analyzing pattern growth. Using a program of General Cellular Automation, a set of rules can be inputted to determine which patches of growth would stay alive or die after the next time interval. This simple interface would allow scientists to simulate how growth patterns would look given a certain set of parameters. Another technique would be to take a series of photos and look at the photos in a time lapsed manner to observe the growth using the rules above. These ideas converge to all propose real life simulation of growing patterns and the interesting part of this foundation is that it could be configured vice versa. Depending on the complexity of the parameters, it might be possible to determine the original configuration of the growth based on what it looks like now. General Cellular Automation presents exiting possibilities for applications in areas of study as varied as tsunami damage prediction to identifying possible sites for extraterrestrial life.

Astrobiology Relation

-There could be a presence of chlorophyll in deep, inaccessible soil crusts of other planets.

-Discovering the causes for patterns in microbial growth could help scientists determine good places to look for extraterrestrial life. The Mathematical Perspective

As a mathematics major participating in this program, this entire experience has been a whirlwind. It seems as if I am introduced into a new topic every hour. Though this is overwhelming at times, it is possible to introduce these topics into a math classroom. From the brainstorming that has taken place among the math majors here, it seems the best integration of these concepts would be through word problems. Students could be directed to find volumes, growth rates, and heights. We could also work to integrate the group based learning that was taking place in the lab. By redirecting the classic lecture based math class into small group work, it’s easy to see how students could facilitate their own learning successfully.

Lesson Ideas

-Give power point that is an understanding of concepts, but with pictures not notes! This would be best to execute an understandable presentation where you talk and students listen and look, not read. This would be an introduction to patterning of organisms.

-By use of General Cellular Automation in the classroom allows students to explore the, “why does doing this make that?” question. Students are given the chance to set their own rules that determine patterns of growth.