Biology Practice Exam Discussion

[Biology24123]

Have you guys done the Neap 2015 exam?

Did you guys find that the questions were a bit more difficult/more confusing than usual?

I did it a few weeks ago and it was pretty tough

[grindr]

I did it a few weeks ago and it was pretty tough

okay, that makes me feel a bit better.
I just did it and I'm looking at these questions like what the f

[Biology24123]

okay, that makes me feel a bit better.
I just did it and I'm looking at these questions like what the f

Our class average was 62%

[grindr]

Our class average was 62%

oh well, it was hard 

[warya]

What score do you need out of 110 for last years exam to get 45+? (assuming high rank+ strong cohort)

[cosine]

Spoiler

Question 1d: Zenkeys are unable to produce offspring. Using your knowledge of gamete formation, suggest why the Zenkey is sterile.

My answer: Zenkeys are sterile because in their genome, they do not have homologous chromosomes present, and so meiosis cannot occur successfully to produce gametes.

VCAA answer: Chromosomes are not homologous and therefore will not pair up during meiosis

Would my answer get full marks? Also when it says sterile, does this just mean that the zenkeys can breed but cannot actually produce the offspring?

Spoiler

Question 8b:
In October 2004, on the remote Indonesian island of Flores, archaeologists discovered bones from a new species
of human called Homo fl oresiensis. These humans were much smaller than modern humans, with adults being
about 1 metre in height and weighing around 25 kilograms. Bones from six or seven individuals have been
discovered in sediments ranging in age from 94 000 to 13 000 years. The skeletons indicate that these humans
had relatively long arms and a very small brain relative to body size, about equivalent to that of a chimpanzee.
They had hard, thick eyebrow ridges and a sharply sloping forehead and no chin. Modern humans, Homo
sapiens, are thought to have evolved somewhere between 55 000 and 35 000 years ago.

It has been suggested that Homo florensis evolved from a population of Homo erectus. List two features from the fossil remains that support this view.

Why was small brains not an acceptable answer? Is it because small brains are not part of the fossil remains, but rather a small cranial capacity would have been a more suitable answer?

Question: Do you need to write in full sentences? For example:

With reference to the pedigree, explain why the locus for white coat colour cannot be X-linked recessive:
"In generation III, individuals 1 had the trait so would be homozygous and III-2 did not have the trait, meaning their female offspring must be heterozygous and not express white colours, but is contradicted in IV-3"

OR

"The locus cannot be X-linked because..."

[Biology24123]

What score do you need out of 110 for last years exam to get 45+? (assuming high rank+ strong cohort)

High 90's - low 100's

[THEBEAST]

Can someone suggest a 3 dot point summary for DNA Replication that would be worth 3 marks in a VCAA exam

[Biology24123]

Can someone suggest a 3 dot point summary for DNA Replication that would be worth 3 marks in a VCAA exam

Double stranded DNA separated by DNA helicase by breaking hydrogen bonds
RNA primer added to both strands
DNA polymerase adds complementary nucleotides to both strands but one of strands is produced in okazaki fragments (lagging strand)
DNA Ligase joins together phosphate sugar backbone in lagging strand

[Biology24123]

So getting an A+ is basically a 40 SS since about 9% of people get an A+

[cosine]

Spoiler

Question 1d: Zenkeys are unable to produce offspring. Using your knowledge of gamete formation, suggest why the Zenkey is sterile.

My answer: Zenkeys are sterile because in their genome, they do not have homologous chromosomes present, and so meiosis cannot occur successfully to produce gametes.

VCAA answer: Chromosomes are not homologous and therefore will not pair up during meiosis

Would my answer get full marks? Also when it says sterile, does this just mean that the zenkeys can breed but cannot actually produce the offspring?

Spoiler

Question 8b:
In October 2004, on the remote Indonesian island of Flores, archaeologists discovered bones from a new species
of human called Homo fl oresiensis. These humans were much smaller than modern humans, with adults being
about 1 metre in height and weighing around 25 kilograms. Bones from six or seven individuals have been
discovered in sediments ranging in age from 94 000 to 13 000 years. The skeletons indicate that these humans
had relatively long arms and a very small brain relative to body size, about equivalent to that of a chimpanzee.
They had hard, thick eyebrow ridges and a sharply sloping forehead and no chin. Modern humans, Homo
sapiens, are thought to have evolved somewhere between 55 000 and 35 000 years ago.

It has been suggested that Homo florensis evolved from a population of Homo erectus. List two features from the fossil remains that support this view.

Why was small brains not an acceptable answer? Is it because small brains are not part of the fossil remains, but rather a small cranial capacity would have been a more suitable answer?

Question: Do you need to write in full sentences? For example:

With reference to the pedigree, explain why the locus for white coat colour cannot be X-linked recessive:
"In generation III, individuals 1 had the trait so would be homozygous and III-2 did not have the trait, meaning their female offspring must be heterozygous and not express white colours, but is contradicted in IV-3"

OR

"The locus cannot be X-linked because..."

Can anyone help me out, please?

And biology24123, yes, most likely. But a friend of mine got an A+ on both the spesh exams and got a 39 raw, so not guaranteed but most likely

[Biology24123]

Can anyone help me out, please?

And biology24123, yes, most likely. But a friend of mine got an A+ on both the spesh exams and got a 39 raw, so not guaranteed but most likely

If the question was 1 mark then you would probably get the mark but you didn't talk about the pairing of homologous chromosomes so you probably wouldn't get 2 marks for that answer

[Bruzzix]

And biology24123, yes, most likely. But a friend of mine got an A+ on both the spesh exams and got a 39 raw, so not guaranteed but most likely

Last year a 39 raw in spec scaled to 50.2

[thushan]

Bloody hell. I swear Specialist scaling was not that crazy when I did it...

[thushan]

Yeah If you are rank then 66-67/75 would get you around a 45

Sounds about right. If you're doing 2010 VCAA or earlier...

I vaguely remember someone getting 67.5 and 67 in 2010 and ended up with a 47. I myself got 68.5 and 72 and ended up with 50 + Premiers - if you wanted to gauge how well you are doing in your past VCAAs.