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Links to the various SACs are below. I have also included some general comments for you all to consider.
Electronic versions of the SACs are below.
biol 4 manipulation of DNA 2009 SAC.doc
biol 4 inheritance 2009 SAC2.doc

Gene technology issues SAC (Monday 12th October)

DNA manipulation SAC

Some general feedback about your SACs. You can collect them when you come in for the biol session.
I feel that the SAC was quite challenging for you as a group. I found many of your responses very frustrating. Although your knowledge of the experiment was quite good, many of you struggled with being able to apply your knowledge and deal with concepts covered a while ago. But this makes the SAC a really good learning opportunity for you as you prepare for the exam.
Some really important points that you must keep in mind, especially during the exam.
  • answer the question that is being asked (eg how did you manipulate the DNA? you really must make the link to the question somewhere in your response)
  • stating a conclusion from the results (description of the results is not good enough and you must extract from the results you obtained, you cannot use other knowledge)
  • if it says draw a labelled diagram, then label it! too many of you drew a diagram without a single label, you need to use every opportunity to show the greatest possible understanding
  • contradictions were present in the last question, some of you said there was no restriction site for EcoR1, yet you drew one in for the last part in the question
  • in the Fragile X syndrome where you were asked to draw a profile for a son with the condition, too many of you are not showing logic, how can you draw more than one band when males only have ONE X-chromosome?
  • I read many responses that were vague and general and indicate too me that you are either not linking your answer to the context of the question (not being careful in your reading of the question) or you simply lack the knowledge/confidence and resort to writing some general statement
  • you must write in full, PCR is not acceptable and will not get you the mark on the VCAA exam. The only abbreviation that is acceptable is DNA (but know how to write the full name), EVERYTHING ELSE must be written fully.

  • many of you summarised the process of polymerase chain reaction well
  • procedure section was also well done
  • quite a few of you drew excellent diagrams for the sticky ends question
  • every questions on the SAC was at least answered accurately by one of you, that means you can learn off each other

Patterns of evolution SAC (Tuesday 1st September)

Like the previous SAC your raw mark will fit into a certain range. If you got over 40 you will get 23-25, over 30 then 20-23, etc. Again i will expect you all to come and see me for a debrief on the SAC.
In assessing your repsonses I was particularly harsh in this SAC on the way you explained ideas and whether you supported your statements with appropriate evidence and reasoning.
Many of you were able to perform better on this SAC compared to the previous one. Again don't focus on your raw score but rather on learning from the SAC, particularly in the area of writing responses that are going to get you maximum marks possible.

Positive aspects include:
  • generally very good analysis of phylogenetic trees and data from molecular comparisons
  • most of the time the terminology was used correctly
  • in all Q1-4 caused little problems
  • there wasn't a single question that at least someone in the class got totally correct

Now, there are some key points for you to remember
  • only one or two of you were able to clearly describe speciation for the leopard question
  • a few more were able to explain natural selection
  • both the above can be answered in point form but all answers must contain the 3 or 4 key elements
  • some responses were too general/vague, you must always try to be specific if info or data is given, even if it isn't directly worded in the questions, why take the chance
  • a conclusion is NOT a description of the results, the moth experiment was poorly done, which I was sort of expecting but not as badly as it turned out

Inheritance SAC (Monday 17th August)

First of all, your raw mark will fit into a certain range that will then give you a score out of 25. For example, you did not need to get 50/50 to get 25 for the SAC. If you got over 40 you would get 24 or 25, if over 30 then 20-23 and so on. So, your result (out of 25) is most likely going to be better than what you think. Do not be discouraged, LEARN from the SAC.
I guess the clear thing for me was that the SAC separated you all quite distinctly. Now, irrespective of the SAC containing some questions that were quite challenging, all of you fit into one or more of the following groups. Some of you are inaccurate in your use of terminology. Some of you do not understand basic concepts. Some of you lacked enough confidence and clarity in using what you know. Some of you have an excellent grasp of everything. Some of you have not checked your understanding adequately enough to ensure that it is correct. There is no doubt that everyone was able to show a good understanding of at least one question. But this is not enough, as you are well aware.
Some important things to remember:
  • too often questions were misread/misinterpeted or not read carefully enough
  • responses did not actually directly answer the question, eg If it says "Do you agree or disagree?" then damn well write in your answer "Agree" or "Disagree".
  • when it says "descibe a piece of evidence from the pedigree", you must be specific, how do I know which individual you are talking about if you just say "the mother", there were four of them.
  • the use of genotype and phenotype were misused as was genes/alleles and the use of recessive/dominant alleles occurred

On a more positive note
  • symbols for alleles and genotypes were generally written well
  • punnet squares and working out gametes were accurate and phenotypic ratios were written properly
  • the first two questions were done very well and these are more VCAA like questions
  • there were lots of excellent responses which contained good use of terminology and reasoning

I will put up a set of solutions to each question, although I think it would be much better if you all contributed to a set of solutions. I can create a specific page for you. There was at least one person in the class who got full marks for each of the questions. I will wait for your response as to what to do.

Give us one week to write answers then fill in what we failed to do.

Sounds like a great idea to me. VM

Link to biol 4 inheritance SAC solutions page.