VCE Biology Question Thread

[QueenSmarty]

On the 2010 biol exam 1 (q2 (b), can my hypothesis be the opposite to the one indicated on the answers? Can i write mice that eat soft pellets will weigh more than animals that eat hard pellet foods?


In lots of multiple choice questions, when determining the age of younger fossils, and if the answers are either one of the two: radio carbon dating or the use of index fossils or anything to do with stratigraphy, which option do we use? Because both can determine the relative age of younger fossils?

Choose 'index fossils' because index fossils determine the relative age of fossils. Radiocarbon dating is used to determine the absolute age (age in years)

[sweetcheeks]

beautiful ty.
another one (dj khaled hehe)

As DNA is an acid it is negatively charged in solution. This is the reason why it moves
through the gel away from the negative electrode.

NEAPs answer for the q asking "what property of DNA enables gel electrophoresis to separate DNA into different sizes' - i wrote due to the slightly negative charge on the phosphorus, but i didnt know DNA is an acid in solution? would i also be right? thanks!

I wouldn't worry about that type of question. That is more a university level chemistry question, but I am fairly certain that you are correct. If I recall, the phosphate group is what makes it an acid.

[geminii]

My biology teacher said, for all the stages of aerobic + anaerobic cellular respiration & photosynthesis, we only need to know the inputs and outputs of each stage, and where each stage happens. However I cam across an exam question by VCAA that asked 'Describe the events in the Kreb's Cycle.' Due to what my teacher said I just assumed we didn't need to know this much detail - I never learnt what goes on within each stage, just the inputs, outputs and location. Is this true? I'm not sure what to think, please help!

[Robert243]

Hey guys, just got a question from tssm 2011 bio exam.
So it asks the DNA sequence shown below ,which codes for a gene.
TAC-GTC-CCC-ATA-GAG-ACC
Establish the mRNA sequence for this section of DNA.
So i wrote
AUG-CAG-GGG-UAU-CUC-UGG
Now most of it was correct except what i put in bold which said it was AUA.
Could anyone explain to me why it was AUA not UAU

[Jordan_312]

It's most likely wrong. You wrote the correct answer. That company is known for wrong questions as well as questions that contradict themselves.

[Gogo14]

For this question, would you have to include a stop codon at the end of the polypeptide? I did, but the answers didn't
http://imgur.com/8CHzMUz

[vox nihili]

For this question, would you have to include a stop codon at the end of the polypeptide? I did, but the answers didn't
http://imgur.com/8CHzMUz

It specifically tells you to write the START codon and then the codons for those amino acids. If it wanted a stop codon, it would have asked.



I suspect that any reasonable exam(iner) would give you the marks for this anyway, as it is reasonable to put in a STOP codon; but where the instructions are that explicit, why would you bother?

[Gogo14]

It specifically tells you to write the START codon and then the codons for those amino acids. If it wanted a stop codon, it would have asked.



I suspect that any reasonable exam(iner) would give you the marks for this anyway, as it is reasonable to put in a STOP codon; but where the instructions are that explicit, why would you bother?

Thanks
Suggest how hormones can produce different responses in different cells (VCAA2013)?
I wrote:
The different cells have different signal transduction pathways, hence resulting in different responses.

Would this be acceptable(1mark)

[vox nihili]

Thanks
Suggest how hormones can produce different responses in different cells (VCAA2013)?
I wrote:
The different cells have different signal transduction pathways, hence resulting in different responses.

Would this be acceptable(1mark)

Yep

[geminii]

My biology teacher said, for all the stages of aerobic + anaerobic cellular respiration & photosynthesis, we only need to know the inputs and outputs of each stage, and where each stage happens. However I cam across an exam question by VCAA that asked 'Describe the events in the Kreb's Cycle.' Due to what my teacher said I just assumed we didn't need to know this much detail - I never learnt what goes on within each stage, just the inputs, outputs and location. Is this true? I'm not sure what to think, please help!

bump

[Gogo14]

http://imgur.com/oTLwUyt
Would my answer for 5b be accepted.
The answers say that the genes were not switched on

[gameboy99]

http://imgur.com/oTLwUyt
Would my answer for 5b be accepted.
The answers say that the genes were not switched on

Not really as you don't mention that even though the genes are present within the individual and have potential to develop the disease, he/she does not as this gene is not activated or not switched on which is why auto antibodies are not present.

[vox nihili]

http://imgur.com/oTLwUyt
Would my answer for 5b be accepted.
The answers say that the genes were not switched on

Not really as you don't mention that even though the genes are present within the individual and have potential to develop the disease, he/she does not as this gene is not activated or not switched on which is why auto antibodies are not present.

I agree with gameboy99 that you probably wouldn't get the marks for it. Your answer is biologically plausible though; although it evidently wasn't what they were looking for.

To be honest, it's not a very good question, as their answer doesn't really reflect the reality of autoimmune diseases either. Beyond VCE, but those autoimmune diseases for which genetic screening is available (best example is coeliac disease) are not revealed when the genes are switched on.

[Gogo14]

Thanks

What property of DNA allows it to be separated into different sizes in gel electrophoresis?
Different company papers each have different answers. Engage says mass only, while neap says charge. I asked this question before, but am asking again as I confused to what to write

[HasibA]

Thanks

What property of DNA allows it to be separated into different sizes in gel electrophoresis?
Different company papers each have different answers. Engage says mass only, while neap says charge. I asked this question before, but am asking again as I confused to what to write

i would say charge, imo, but again, i think this wont be asked on the real VCAA exam