ExamEssay Discussion Signals, Translocation, Scales Describing Systems

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Exam/Essay DiscussionSignals, Translocation,
ScalesDescribing Systems Processes
Transposons as normal

• Nov. 8, 2005

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General Suggestions for Essays

• State the context / introduction / issue to be
  addressed in your essay.
• Orient / identify the principles, requirements,
  context of the processes.
• Describe how the parts affect / depend on one
  another to produce the desired consequences.
• Present broader implications, unknowns
  assumptions critical to confidence in conclusions
  or explanations (models).
• Give citations (Author(s), date, citation) and
  attach copy of source, with analysis of
  reliability and credibility if needed/requested.

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Answering Exam Questions

• Is the question a request to explain / analyze a
  result, a process, or a prediction?
• What are the spatial scales that are to be
  covered in explanation?
• What is the time window of explanation?
• What living structures, modifications and flows
  are needed for processes and / or resulting from
  changes?
• What are implications or caveats needed?

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Insuring Your Credibility and Reliability

• Follow KISs Principle (Keep it simple!)
• Express your ideas in your own words whenever
  possible, and clearly give credit for your
  sources. Only very rarely use a quote of more
  than one or two words or terms. (Any idea needs a
  credit usually with a reference if its not
  original.)
• Analyze your sources become informed
  skeptics and write accordingly.

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Natural Transposons

• When controlled by cell processes, they can be
  important modes for differentiation and cell
  function. (e.g. may comprise gt half of the genome
  and most are 1,000 bases)
• Transposons are found in multiple copies
• Many are genes without a promoter region
• Often are around centromeres and telomeres
• May have active form as RNA
• Only a few are active
• Some genes originated as transposons

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Is this DNA from ourancestors, or fromother
species?
Not only are we anecosystem with bacteria,but
our genome isan aggregation frommany species.
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Transposon Activities

• Transposon movements may be associated with DNA
  replication

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May Cause Chromosome Rearrange-ments
The direct repeatsmay arise fromcopies as shown
onprevious slide.
All GMOs are madewith transposons,synthesized
in lab.
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Transposons are Clonally Inheritedfound in
both Plants and Animals
If GMO has a changeand it is in
reproductivetissue, it may betransmitted
tooffspring.
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Questions to Ponder

• If transposons are so common in the genome, what
  keeps our mutation rate relatively low? (Relative
  to what rate?)
• What benefits might be found in having mutable
  loci in our genome?
• What keeps the cost of mutable loci from
  overwhelming an individual, or a population, or a
  species?
• What is the price we pay for having mutable loci
  in our genome?