Imagine you are an exploratory astronaut looking for life throughout the universe. One day you encounter a planet that has no carbon present on its surface. However, your instruments register movement and a variety of other signs that make you think life exists on the surface.
Part 1: Before taking a potentially dangerous trip to the surface, you must outline a theoretical framework in which another element can serve as a backbone for macromolecules. (Hint: look for an element on the periodic table that would act similarly to carbon.) Begin by describing this new backbone, including how compounds and macromolecules would form. Detail at least 2 chemical reactions forming macromolecules with this backbone. You may wish add supporting diagrams (created or obtained). Be sure to include references as appropriate.
Part 2: Your theoretical framework is deemed strong enough to justify a trip landside. Once there, you are authorized to collect a simple “organism” for experimental use. Collect your specimen(s) and then design a full experiment that will test at least two characteristics that define biological life on Earth. Be sure to include all the relevant parts of an experiment and describe how you would analyze and present the data, results and conclusions.
Part 1:
Look for an element on the periodic table that would act similarly to carbon. Once you have identified one, be sure to discuss the following in your justification.
• Examine and discuss the outer electron shell and chemical bonding characteristics of this new element.
• Specifically describe how the outer shell would make this new element bond as carbon does.
• Then you should specifically discuss or draw two chemical reactions to form macromolecules with this different element. For example, make a molecule like glucose but without any carbons (replace carbon with your new element). Images will work great here; they can be hand or computer drawn or you may be able to find some on the internet.
• Cite your references!
Part 2:
Choose two of the defining characteristics of life and design an experiment to test each in your alien lifeform. Be sure that your design includes all the following points.
• Hypothesis
• Dependent and independent variables
• Control and experimental groups
• Standardized variables
• The specific type of data you would collect
• How you would analyze and present these data
• What pieces of data/evidence you would need to support your hypothesis. Alternatively, what evidence would disprove your hypothesis?
Remember to keep things simple and observable. You will most likely have to design 2 different experiments to test the different characteristics.
