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Author Topic: VCE Biology Question Thread  (Read 3571909 times)  Share 

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AhNeon

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Re: VCE Biology Question Thread
« Reply #8325 on: September 28, 2016, 07:25:10 pm »
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Are you sure it was 2010? I can't find the question.

I could very well be wrong, so want to clarify :)

It's question 17 of exam 1.

AhNeon

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Re: VCE Biology Question Thread
« Reply #8326 on: September 28, 2016, 07:35:04 pm »
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How does having higher MtDNA variation in Africa support the out-of-africa theory?

HasibA

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Re: VCE Biology Question Thread
« Reply #8327 on: September 28, 2016, 07:52:20 pm »
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How does having higher MtDNA variation in Africa support the out-of-africa theory?
this an exam question?
well i think because mtDNA is mitochondrially passed, and thus maternally inherited. also mtDNA does not undergo crossing over, and recombination.
so using these facts- perhaps having more variation shows theres more genetic differences in africa, and how humans evolved from africa and moved out, replacing homo erectus populations around the world.

soo-conclusion- having higher mtDNA shows that maternally inherited traits had a lot of variation, supporting the out of africa theory which states modern humans evolved out of africa, and more variation=more likelihood of evolution=synonymous to humans evolving in africa.

[hope this made sense and nothing was wrong, im realllly bad at explaining- sorry if i confused you- but essentialy theres more gentic variation, which is usually linked with evolution, which support the theory stating modern humans evovled from within africa]

:)
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Re: VCE Biology Question Thread
« Reply #8328 on: September 28, 2016, 07:59:01 pm »
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It's question 17 of exam 1.

Hmm it looks like you do need to know it. Personally, I think it's an unreasonable question and shouldn't have been put on the exam. The information I can find is conflicting, but most point to the idea that the absorbance max for chlrophyll (and other plant pigments) is in the blue part of the spectrum.
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Calebark

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Re: VCE Biology Question Thread
« Reply #8329 on: September 28, 2016, 08:43:43 pm »
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If any of you guys would be able to do any of these questions or answer them would be super great!
(For the multiple choice, can you please explain why each option is wrong like in a sentence or something?)


CHAPTER 11/12: (EXAM: 2)
MULTIPLE CHOICE:

Q30 (2013)
Q23 (2015)
(I KNOW HOW TO DO IT, JUST WANT TO KNOW IF THE SEQUENCE OF AMINO ACIDS TABLE REPRESENT MRNA CODONS OR TRNA ANTI-CODONS? BECAUSE THE AMINO ACID ‘ASN’ CODES FOR “AAC” (CODON), SO WHEN YOU CONVERT IT TO DNA IT BECOMES ‘TTG’ SO IF THE TABLE REPRESENTS MRNA CODONS, ALL WE DO IS SWITCH IT BACK TO DNA, BUT HOW ABOUT IF THE TABLE REPRESENTS TRNA ANTI-CODONS?? OR IS THIS NOT POSSIBLE? IS THE TABLE OF AMINO ACIDS IS ALWAYS REPRESENTED AS MRNA CODONS??
Q11 (2011)

SHORT–ANSWER:
Q5 d (ii) (2011)
Q4 (a) (2012) (CAN YOU PLEASE DRAW THIS FOR ME)
Q6 (c) (2015) (HOW IS THAT ANSWER POSSIBLE?)
Q8 a (i) (Which of the STOP or START codons do we include when counting? Because I know that we just have to count the exons in bold?)
Q8 (iii) (2015) (Does this mean "TAC" is not to be included when counting amino acid sequence as "AAT" is the 5th CODON instead of "AAA"?)

THANKS SOOO MUCH!! and super sorry if i'm bothering you

Sure, do my best - although it may better for your learning next time to walk through your reasoning thus far :)

2013, MC, Q30

Okay, so this is about restriction enzymes. Restriction enzymes cut at specific sequences. You'll have to look at the options given above Q29. You can see how they cut at this image. Note how the red represents AluI and the blue represents HindIII.

2015, MC, Q23

Yeah, this is a pretty confusing layout. This table refers to the RNA sequence of the complementary strand. You'll see that we need Asn-Gly-Pro-Arg-Ser, so let's go through this systematically
Asn → AAU, AAC → TTA,  TTG. This eliminates D.
Gly → GGU, GGC, GGA, GGG → CCA, CCG, CCT, CCC. This eliminates B.
The next two for A and B are identical, so let's skip to the last one, which is different.
Ser → UCU, UCA, UCC, UCG, AGU, AGC → AGT, AGT, AGG, AGC, TCA, TCG. This eliminates C.
Following this, A is the answer,

2015, SA, 6c
I'm afraid I can't help here, I lost this mark, and was planning on asking this myself, haha.

2015, SA, 8ai
The answer to your question is in the stem of the question (don't worry, I have a habit of missing things too). It says "the DNA triplet TAC indicates START and codes for the amino acid methionine that remains in the polypeptide.". It does not say that the STOP triplet stays in the polypeptide, so count the START codon and the remaining, non-STOP exons.

2015, SA, 8ii
From what I understand, you count everything up to the mutation. Remember that STOP codons aren't included in the polypeptide, and that the possible STOP codons are - from the stem-, ATC, ATT, and ACT. By looking at the sixth triplet, AAT, you can see that a substitution mutation could occur to change it to the triplet ATT.

For the questions from 2011 and 2012, you'll have to indicate which exam it is from, as there are two exams for that year,
« Last Edit: September 28, 2016, 09:09:08 pm by Calebark »
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Gogo14

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Re: VCE Biology Question Thread
« Reply #8330 on: September 28, 2016, 11:55:58 pm »
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Are you sure it was 2010? I can't find the question.

I could very well be wrong, so want to clarify :)
Yep, question 17 and 23 of multiple choice
2016: Bio[45]
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PM if want help/advice | VCE tutoring available too- just PM

Gogo14

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Re: VCE Biology Question Thread
« Reply #8331 on: September 29, 2016, 12:07:51 am »
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Is there an answer book for NoB?
2016: Bio[45]
2017: Eng[43];Chem[47];Methods[49];Spesh[46];Physics[44]
2018+: B-Biomed @unimelb

PM if want help/advice | VCE tutoring available too- just PM

Calebark

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Re: VCE Biology Question Thread
« Reply #8332 on: September 29, 2016, 12:33:44 am »
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Is there an answer book for NoB?

I suck at acronyms, do you mean Nature of Biology?

I don't think ATAR Notes allows exchanging such materials (from memory, it must be bought).

Moderator edit: Removed suggestion that is questionable from post.
« Last Edit: September 29, 2016, 12:38:26 am by Aaron »
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Vaike

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Re: VCE Biology Question Thread
« Reply #8333 on: September 29, 2016, 12:47:08 am »
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How does having higher MtDNA variation in Africa support the out-of-africa theory?

My understanding is that:
-Highest mtDNA variation would expected to be found in the place in which homo sapiens have been living longest, due to more time to allow for genetic mutations to occur and be passed on.
-Also, when migrating out of Africa, only small populations would have migrated out. This would result in large European populations being formed from only a few founders with limited genetic variability, making the mtDNA variance in non African populations lower due to the founder effect.

hodang

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Re: VCE Biology Question Thread
« Reply #8334 on: September 29, 2016, 09:43:50 am »
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Sure, do my best - although it may better for your learning next time to walk through your reasoning thus far :)

2013, MC, Q30

Okay, so this is about restriction enzymes. Restriction enzymes cut at specific sequences. You'll have to look at the options given above Q29. You can see how they cut at this image. Note how the red represents AluI and the blue represents HindIII.

2015, MC, Q23

Yeah, this is a pretty confusing layout. This table refers to the RNA sequence of the complementary strand. You'll see that we need Asn-Gly-Pro-Arg-Ser, so let's go through this systematically
Asn → AAU, AAC → TTA,  TTG. This eliminates D.
Gly → GGU, GGC, GGA, GGG → CCA, CCG, CCT, CCC. This eliminates B.
The next two for A and B are identical, so let's skip to the last one, which is different.
Ser → UCU, UCA, UCC, UCG, AGU, AGC → AGT, AGT, AGG, AGC, TCA, TCG. This eliminates C.
Following this, A is the answer,

2015, SA, 6c
I'm afraid I can't help here, I lost this mark, and was planning on asking this myself, haha.

2015, SA, 8ai
The answer to your question is in the stem of the question (don't worry, I have a habit of missing things too). It says "the DNA triplet TAC indicates START and codes for the amino acid methionine that remains in the polypeptide.". It does not say that the STOP triplet stays in the polypeptide, so count the START codon and the remaining, non-STOP exons.

2015, SA, 8ii
From what I understand, you count everything up to the mutation. Remember that STOP codons aren't included in the polypeptide, and that the possible STOP codons are - from the stem-, ATC, ATT, and ACT. By looking at the sixth triplet, AAT, you can see that a substitution mutation could occur to change it to the triplet ATT.

For the questions from 2011 and 2012, you'll have to indicate which exam it is from, as there are two exams for that year,


They are from BIOL EXAM 2 for the 2011 and 2012 questions :) BTW thankyou soo much! You have been super helpful!!

As for question: 2015, MC, Q23
When you said "This table refers to the RNA sequence of the complementary strand"

How can we know what the table represents? This is what confused me. How do we know if the table represents tRNA or mRNA btw would the answer be any different if the table represented tRNA or would the answer still be A?


hodang

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Re: VCE Biology Question Thread
« Reply #8335 on: September 29, 2016, 09:59:10 am »
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Hey Calebark, can you also try these out from

(These questions are all from the BIOL EXAM 2) Unit 4

CHAPTER 9/10: (EXAM: 2)
MULTIPLE CHOICE:
Q7 (2009)
Q6 (2012) (Would the 1st child ALSO be a 1 in 4 chance?)
Q26, Q27 (2013)

SHORT-ANSWER:
Q8 c (iii) (2015)

The Usual Student

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Re: VCE Biology Question Thread
« Reply #8336 on: September 29, 2016, 02:22:07 pm »
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Can someone explain to how the structure of glycogen,starch and cellulose reflects their function?

And I read in tsfx that " these bonds are hydrophilic" so bonds can be hydrophobic and hydrophilic or is it just the molecule in totality.

Calebark

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Re: VCE Biology Question Thread
« Reply #8337 on: September 29, 2016, 03:34:00 pm »
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How can we know what the table represents? This is what confused me. How do we know if the table represents tRNA or mRNA btw would the answer be any different if the table represented tRNA or would the answer still be A?

They are grouped in threes, so they are codons. Codons are mRNA, and mRNA is single-stranded, and transcribed from a template strand of DNA. Thus, it is complementary to the DNA strand. tRNA is complementary to mRNA. So, you could have CAT (template strand) → GUA (mRNA) → CAU (tRNA). I've never seen a question about this before, so I doubt you need to know this.

2011, MC, 11
Okay, so this is about DNA replication. It's a bit hard to explain well using text, so I will use my favourite learning tool, and use this image

2011, SA, 5dii
So let's assign H as the dominant allele of HERDA, and h as the recessive, trait allele of HERDA.
Let's assign O as the dominant allele of OLWS, and o as the recessive allele. We don't know if this is recessive or dominant. I'll do the cross assuming if it's recessive, then you can try it as dominant.
Now, we have to see how many would be phenotypically normal. This would mean that anything with hh or oo is not phenotypically normal.
It's hard to do a Punnet Square in text, so again, I will use an image. As we can see, 7/16 will be affected, so 9/16 will be phenotypically normal.

2012, SA, 4a
This is a recreation of what I did on that exam. It's a bit tricky, but this is a good resource to help learn.

Unfortunately, I have to go, so I can't help with those questions just yet -- for now, go through each question, and type what you've done so far, so it'll be easier to help :)
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AhNeon

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Re: VCE Biology Question Thread
« Reply #8338 on: September 29, 2016, 05:24:03 pm »
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Hmm it looks like you do need to know it. Personally, I think it's an unreasonable question and shouldn't have been put on the exam. The information I can find is conflicting, but most point to the idea that the absorbance max for chlrophyll (and other plant pigments) is in the blue part of the spectrum.
But since Vcaa have basically said that red is the correct response through those questions, i'm guessing that if the question came up again, red would be the best response, right?

HasibA

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Re: VCE Biology Question Thread
« Reply #8339 on: September 29, 2016, 05:28:07 pm »
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But since Vcaa have basically said that red is the correct response through those questions, i'm guessing that if the question came up again, red would be the best response, right?
yeah stick with what VCAA have said in examination reports! they shouldn't deduct any marks if it's verbatim to what they've stated :)
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