Origin of Life Think Quest

Origin Of Life Think Quest

Activities / Procedures:
1. In your small groups, read the following quote from a New York Times article:  “Enshrined in high school textbooks, the Miller-Urey experiment raised expectations that scientists could unravel the origins of life with simple chemistry experiments.”

2. Now, use your online textbooks and the following videos: http://www.youtube.com/watch?v=j9ZRHoawyOg and http://www.youtube.com/watch?v=63IoOLXmzKg(Familiarize yourself with the famous Miller-Urey experiments of 1953 by completing the following Think Quest that will prepare you for reading an article about new evidence related to these experiments.

Quest Questions (post answers in your online notebook under “Notes”:
-Who were Stanley Miller and Harold Urey? Scientists who discovered how organic, life substances could be formed under the conditions the atmosphere was under during the first years of the earth’s existence.
-What was the Miller-Urey experiment trying to simulate? The conditions of the atmosphere.
-When was the Miller-Urey Experiment performed? During the early 50’s.

-Describe the Miller-Urey Experiment. They recreated atmospheric conditions during the first years of life, and subjected them to either electricity or freezing, and observed what molecules were created.
-What was discovered by the Miller-Urey Experiment? That amino acids and adenine could be created under the above-mentioned conditions.
-Are the results of the Miller-Urey Experiment still considered relevant today? Why or why not? Yes, but by a much more varying degree from when it was first introduced. There are so many more hypothesis now, that the amino acids could have formed from meteorites from space.

--Compare and contrast this experiment to your “Coacervates Lab” (review it in your online notebook). We were able to create cell-like organisms through the use of carbohydrates and proteins.
- List any Need to Knows you have concerning the experiment and the conclusions. Did all of these organisms form together to make the first cells?

- What was the significance of the swan-neck flask experiments and who performed them? It proved that spontaneous generation did not exist, and there were no vital substances in the air for living. Louis Pasteur conducted this experiment.

- What was the significance of the blender experiments and who performed them? Alfred Hershey and Martha Chase used a kitchen blender to prove that DNA exists, and how viruses infect their hosts.

- How do the blender, swan-neck flask, and Urey-Miller experiments relate to one another and your current project? Through the incorporation of all of the created molecules, life is possible to be made. With our current project, we are talking about the evolution of animals, and the fact that the environment surrounding can affect organisms, we will be able to have our organism evolve.

3.  With your partners, read and discuss the article “From Old Vials, New Hints on Origin of Life,” (http://www.nytimes.com/learning/teachers/featured_articles/20081021tuesday.html) focusing on the following questions:
a. What would a proponent of Dr. Miller say about his experiment today? What would a critic say about it? They would say that there are so many variables in which life could have taken place. A critic would say that it is very improbable that anything of such degree could have taken place.
b. Why did the addition of steam to the experiment by Dr. Miller interest Dr. Jeffrey L. Bada? The H2O made for a better environment for chemical reactions to take place.
c. What did Dr. Bada and Adam Johnson discover in the “brown residue at the bottom of an old vial?” Why was it significant? There were more amino acids than originally conceived by man, and it helped the believe that – certainly – complex proteins could have been formed in these conditions.
d. What other places have been suggested as likely locations for the origin of life and why? Do you agree or disagree with Dr. Bada’s assessment that “you want to consider everything,” and why or why not? The ocean was considered. Yes, you do want to consider everything, because given billions of years, life had to start from somewhere. If simulated, then we can find the origins of life.

e. How does knowing about climate past and present help us understand life and how it survives? We are able to see under what conditions life can be sustained.

f. Do you think we have a responsibility to attempt to curtail or reverse human’s influences on the environment?  Why or why not? Yes, because we are the more conscious beings on earth. We subjected the earth to these conditions, and now we are responsible for bringing it back to a healthy state.