VCE Biology Exam - 01/11/19 - Discussion/Questions/Solutions

[3086]

Use this as a mild reference and assume an A+ is 83% for 2019

[PhoenixxFire]

Use this as a mild reference and assume an A+ is 83% for 2019

A+ cutoff is very unlikely to be that high.

does anyone have an idea of the study score id get if im averaging 88% on sacs and 84% on exam?

Likely in the area of 39-42 dependent on how your SACs scale.

[aarontran]

For question 4.c, I said stated that a vaccine would be ineffective, as a vaccine would just produce more IgE anitbodies that would prime more mast cells to heighten the allergic reaction, as more histamine is released. Would this be considered wrong?

[Didge123]

Hello I ranked 1 with sac average of around 98%. I think I got around 85-90% on the exam. Would anyone be able to predict study score around about?

[3086]

 

Hello I ranked 1 with sac average of around 98%. I think I got around 85-90% on the exam. Would anyone be able to predict study score around about?

44-46 imo

[3086]

A+ cutoff is very unlikely to be that high.

Tho I thought the exam was fairly straightforward in everyone's opinions and everyone seemed to do well? What do you reckon

[tdowler100]

There were certainly questions that were straightforward and I would agree with that to a point . However, remember that there are a lot of people sitting this exam in the state and there will be a lot of kids (especially in rural areas) who will find the exam challenging in comparison to last years.

[PhoenixxFire]

For question 4.c, I said stated that a vaccine would be ineffective, as a vaccine would just produce more IgE anitbodies that would prime more mast cells to heighten the allergic reaction, as more histamine is released. Would this be considered wrong?

It's possible that either yes or no will be accepted with appropriate justification. If that is the case, this explanation may be accepted.

Tho I thought the exam was fairly straightforward in everyone's opinions and everyone seemed to do well? What do you reckon

People did seem to find it easier and I won't be at all surprised by the cutoff going up, I just don't think it'll go up that much - the cutoff has never increased by that much in the years since 2013 when the exam format changed.

[tdowler100]

With question 8c. I said size of fragment, charge of fragment and contamination from other dna. Would those answers be acceptable. And for 8d, ethical issue was who has right to the information and privacy of the patient. Are they acceptable?

[Erutepa]

With question 8c. I said size of fragment, charge of fragment and contamination from other dna. Would those answers be acceptable. And for 8d, ethical issue was who has right to the information and privacy of the patient. Are they acceptable?

You will get a mark for the first factor - However I think the other two factors listed would be marked as incorrect
Contamination by other DNA isn't a factor that affects DNA's movement. It will affect the banding pattern, but the movement of DNA through the gel will be unaffected.
All DNA has the same mass:charge ratio, which essentially means that all DNA will experience the same force in an electric field - regaurdless of the magnitude of the DNA's charge charge.

[Sconey]

Does anyone remember the exact phrasing of Question 8c); the one about the 3 factors affecting DNA movement in gel.

[Matthew_Whelan]

You will get a mark for the first factor - However I think the other two factors listed would be marked as incorrect
Contamination by other DNA isn't a factor that affects DNA's movement. It will affect the banding pattern, but the movement of DNA through the gel will be unaffected.
All DNA has the same mass:charge ratio, which essentially means that all DNA will experience the same force in an electric field - regaurdless of the magnitude of the DNA's charge charge.

Wouldn’t charge be a factor that allows DNA to migrate across the gel? It doesn’t vary between DNA but it is still valid i think.

[PhoenixxFire]

Does anyone remember the exact phrasing of Question 8c); the one about the 3 factors affecting DNA movement in gel.

There wasn't anything too specific in the phrasing, the three factors just had to affect the movement of dna fragments through the gel.

And for 8d, ethical issue was who has right to the information and privacy of the patient. Are they acceptable?

You'd probably get the mark for that. The question does ask about ethical implications arising "from this finding" but it seem like the finding being referred to is that a couple has the same mutation - so I don't think the issue would have to do with a fetus/potential fetus directly.

Wouldn’t charge be a factor that allows DNA to migrate across the gel? It doesn’t vary between DNA but it is still valid i think.

It's possible that it could be accepted. The way the question is phrased implies that it wants things that affect how dna goes through migration, not things that effect whether it will migrate. I'm not sure if vcaa will make that distinction though. By asking for things that affect its migration, you're implying that migration occurs - the presence of charge only ensures that it does occur, and may therefore be irrelevant.

[Highway_end]

Does anyone remember the exact phrasing of Question 8c); the one about the 3 factors affecting DNA movement in gel.

It was "Discuss three factors that affect the migration of DNA fragments through the agarose gel during gel electrophoresis."

[Sconey]

It was "Discuss three factors that affect the migration of DNA fragments through the agarose gel during gel electrophoresis."

Thanks mate. I said time as one of mine; as in the time allowed for since loading the fragments for movement. I don't reckon that will be counted