Cogitania

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Life's boundaries

Today we explored a planet filled with extreme conditions and organisms that thrive at these extremes - Earth.

Extremophiles are organisms specially adapted to the extreme condition(s) they inhabit. Four types of extreme conditions - temperature, pressure, composition and radiation - were explored.

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The students started by predicting the types of habitats thermophiles and psychrophiles, those inhabiting hot and cold temperatures, respectively. Each student predicted which range of temperatures life may exist, and discussed the reasoning behind their choices. These students then journied throughout Earth (via Google Earth) to see the types of ecosystems and the challenges they pose to psychrophiles and thermophiles, respectively.

Each student then dove into the world of piezophiles, again predicting where to find these pressure-loving organisms, and exploration of the Marianas Trench. Halophiles, salt-loving organisms, were then discussed, with excellent input about where these extremophiles may be found.

We ended our discussion about radiation-resistant / radiotrophic extremophiles, which we will continue discussing in our next session. Next time the students will explore radiation and nuclear chemistry, what it means (biologically) to be alive, as well as review protein structure. This will set up a foundation for predicting what adaptations extremophilic proteins may accumulate in order to ensure their proper functioning.