27 Jul “The Cell, Lokiarcharum, And RRNA”
“The Cell, Lokiarcharum, and rRNA”
For your primary post, please respond to one of the following three topics with a post of at least 125 words that addresses each point given in the instructions. Also, please reply to at least one fellow student on any topic.
: Introduction to the Cell. Watch the Khan Academy video “Introduction to the cell” (1)* and then address the following issues.
- (a) In the video, the narrator says that we might think that since cells are so small, that they must be simple, but “nothing could be further from the truth.” What did he mean by that?
- (b) Describe features that are only found in eukaryotic (but not prokaryotic) cells.
- (c) Did anything in this video surprise you, or was it mainly a recap of material you already knew?
Topic 2 [article]: Lokiarchaeum. Read about Lokiarcheum in the article by Yong (2)* and/or the article by Zimmer (3)*. Both articles describe recently discovered evidence about a previously unknown organism. Then, address the following issues:
- (a) Lokiarchaeum may be a “transitional form” between archaea and eukarya. What evidence suggests this?
- (b) Describe one way that this relates to this week’s lesson.
- (c) Cite whichever article you use. If you use both, cite them both. There’s no particular reason why you should need any other source, but if you do use any other source, you must cite it, too.
Topic 3 [research]: Carl Woese. Carl Woese (b. 1928, d. 2012) worked out a new method for classifying organisms based on RNA from their ribosomes. This is called ribosomal RNA (rRNA). Research Carl Woese’s research on the Internet, and then address the following issues:
- (a) Describe the basic logic of this Woese’s approach. In other words, how can you tell if two organisms are closely-related or distantly-related from their rRNA?
- (b) Name one of Woese’s most important findings.
- (c) Describe one way that this relates to this week’s lesson.
- (d) Don’t forget to cite your source or sources!
References (in Strayer Writing Standards format).
- Khan Academy, November 29, 2017. Introduction to the cell, https://www.youtube.com/watch?v=5KfHxF6Vhps
- Ed Yong, May 6, 2015. New Loki microbe is closest relative to all complex life, http://phenomena.nationalgeographic.com/2015/05/06/new-loki-microbe-is-closest-relative-to-all-complex-life/
- Carl Zimmer, May 6, 2015, Under the sea, a missing link in the evolution of complex cells, http://www.nytimes.com/2015/05/07/science/under-the-sea-a-missing-link-in-the-evolution-of-complex-cells.html?_r=0