2014 VCE Biology Exam Solutions by Scooby

[Reus]

For question 10.A would I be wrong if I mentioned the sex of the bee in the phenotype?

I put 25% for Red Male, 25% Black male...etc.

I wrote 1 Red Male, 1 Black male...etc is that okay? I forgot to at least do ¼ or 25% (time constraints didn't help)

[heymanhru]

I wrote 1 Red Male, 1 Black male...etc is that okay? I forgot to at least do ¼ or 25% (time constraints didn't help)

If I recall correctly I did the same thing (1:1:1:1), I'm guessing it should be okay  .

Edit: If you wrote it as in 1 Red Male : 1 Black male : 1 Red Female : 1 Black Female I don't see why it could possibly be wrong, that's what I did anyway lol

[Reus]

Hope it's acceptable

[andreandre]

Thanks for all of these! Could you peles post question 2 as well!? It's been stressing me out!

[katiesaliba]

If I recall correctly I did the same thing (1:1:1:1), I'm guessing it should be okay  .

Edit: If you wrote it as in 1 Red Male : 1 Black male : 1 Red Female : 1 Black Female I don't see why it could possibly be wrong, that's what I did anyway lol

I also wrote the same thing

[Reus]

If Katie got it right, we got it right 

[katiesaliba]

If Katie got it right, we got it right 

Ahh no, here's hoping  .

[Litsy03]

There was a question regarding the steps and procedures of PCR (Polymerase Chain Reaction). It was a 3 mark question so I assume there are 3 parts to it. I listed each step- explaining what occured at each step including the appropriate temperatures at which the different events occured. However, I am worried that I forgot to mention that the process should be repeated at the end. Do you think I will lose a whole mark for this? Technically speaking though, the question asked how scientists may amplify samples of DNA and even one cycle of PCR would produce 2 new strands of DNA, technically 'amplifying' the original amount... So my question is, do you think I will lose an entire mark although I listed all 3 steps and all important factors correctly?

[tsouls]

For q 11.d (behavioural changes due to bipedalism) could I have said 'instead of being arboreal (living in trees) they now mostly live on the flat grasslands' ?

[tsouls]

There was a question regarding the steps and procedures of PCR (Polymerase Chain Reaction). It was a 3 mark question so I assume there are 3 parts to it. I listed each step- explaining what occured at each step including the appropriate temperatures at which the different events occured. However, I am worried that I forgot to mention that the process should be repeated at the end. Do you think I will lose a whole mark for this? Technically speaking though, the question asked how scientists may amplify samples of DNA and even one cycle of PCR would produce 2 new strands of DNA, technically 'amplifying' the original amount... So my question is, do you think I will lose an entire mark although I listed all 3 steps and all important factors correctly?

This question has been asked before and here was VCAA's answer:

 heat DNA to approximately 90 °C or to separate strands
 cool to approximately 50 °C or to anneal/attach primers
 heat to approx 72 °C or Taq/DNA polymerase copies strands
 repeat cycle.
Many students set out clear answers that demonstrated a sound understanding of the process. Many other students
missed out on full marks by not stating that the process needed to be repeated.

Although, this question was out of 4 marks and the one on our exam was maybe out of 3 marks?
But yeah might lose the mark.. but hopefully not because i think i forgot to say repeat cycle as well

[dankfrank420]

For q 11.d (behavioural changes due to bipedalism) could I have said 'instead of being arboreal (living in trees) they now mostly live on the flat grasslands' ?

I think this is a question where VCAA will accept a range of suitable answers. I wrote:

- freed up hands, facilitating use of tools
- more efficient travel, facilitating various migrations

So as long as it makes sense then VCAA will award you marks.

[Reus]

This question has been asked before and here was VCAA's answer:

 heat DNA to approximately 90 °C or to separate strands
 cool to approximately 50 °C or to anneal/attach primers
 heat to approx 72 °C or Taq/DNA polymerase copies strands
 repeat cycle.
Many students set out clear answers that demonstrated a sound understanding of the process. Many other students
missed out on full marks by not stating that the process needed to be repeated.

So yes i think you will. But i think i forgot to say repeat cycle too

I only stated the specific temperature for denaturation/heating (step 1) however I did say at cooler temperatures for step 2 and 3. Would that be enough? I did say that the process needed to be repeated.

[grannysmith]

I think this is a question where VCAA will accept a range of suitable answers. I wrote:

- freed up hands, facilitating use of tools
- more efficient travel, facilitating various migrations

So as long as it makes sense then VCAA will award you marks.

This is exactly what I wrote..

[dankfrank420]

This is exactly what I wrote..

What's that they say about great minds?

[Scooby]

Everyone asking about whether you needed to mention the sex of the offspring for one of the monohybrid cross questions - since sex didn't influence the likelihood of the offspring having either trait, I chose not to include it, but you can if you want to, of course, as has been mentioned

As for the question about the Woolly mammoths, yeah, it was a ambiguous, but since the question asked for "how" the new species arose (ie. the mechanism of evolution), they were probably looking for you to answer it in the context of natural selection 

You'll still get some marks for a description of allopatric speciation though!