ATAR Notes: Forum

Archived Discussion => 2010 => End-of-year exams => Exam Discussion => Victoria => Biology => Topic started by: lexitu on October 31, 2010, 12:49:14 am

Title: SECTION A - Suggested Answers
Post by: lexitu on October 31, 2010, 12:49:14 am
1 - C

2 - B

3 - D

4 - D

5 - B

6 - B

7 - C

8 - C

9 - C

10 - D

11 - B

12 - A

13 - A

14 - D

15 - B

16 - D

17 - C

18 - D

19 - D

20 - B

21 - A

22 - B

23 - A

24 - C

25 - A

Please let me know if you disagree.
Title: Re: SECTION A - Suggested Answers
Post by: Milkshake on October 31, 2010, 12:51:41 am
1C

The rest are the responses I put as well, pretty sure they're good.
Title: Re: SECTION A - Suggested Answers
Post by: lexitu on October 31, 2010, 12:52:58 am
Ohh whoops that's a typo. My bad. It's clearly 1 - C.
Title: Re: SECTION A - Suggested Answers
Post by: onerealsmartass on October 31, 2010, 12:53:39 am
I thuoght Q1 was binary fission :( fml
Title: Re: SECTION A - Suggested Answers
Post by: onerealsmartass on October 31, 2010, 12:54:04 am
OH few :) felt soooo down
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 12:55:37 am
i put 24C as

- anatomy of flagella are different
- functions are the same
- the species do not have a recent common ancestor, you had to go back to the kingdom to find their common ancestry

so analogous structures
Title: Re: SECTION A - Suggested Answers
Post by: lexitu on October 31, 2010, 12:58:19 am
Okay, hmm damn. I agree with you now. The last line says it all.
Title: Re: SECTION A - Suggested Answers
Post by: onerealsmartass on October 31, 2010, 12:59:44 am
man im tired... getting the exam was worth the wait :)
i think im on 23/25 good enough for me :D
thushan pls tell me 25/25 lol
good night guys.
Title: Re: SECTION A - Suggested Answers
Post by: stonecold on October 31, 2010, 01:00:19 am
24 C too...

other than that, looking good.

edit: and it was 23 A and 24 C aleitu.  I think you mixed them up.
Title: Re: SECTION A - Suggested Answers
Post by: onerealsmartass on October 31, 2010, 01:01:36 am
also do you still think that we had to mention which jaw was the australopithecus? i compared them in my differneces...
Title: Re: SECTION A - Suggested Answers
Post by: stonecold on October 31, 2010, 01:13:59 am
here are my answers

CBDDB BCCCD BAADB DCDDB ABACA

i put 23A as:

- proportion of heterozygous individuals skyrocketed as soon as DDT spraying reduced
- in 1966 the percentage of heterozygotes was similar to number of homozygous resistant, something like 50 homo dom, 40 hetero, 5 homo rec

say 50 RR, 45 RS, 5 SS --> no. R = 145, no. S = 55

so C is not right, unless i made a mistake?

yeah, it is A.  he had it as A before and mixed it up.

It is clear heterozygous advantage occurred, as their frequency is higher than that of the other 2.
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 01:18:13 am
Yeah I deleted the post when I saw your edit :P whoops
Title: Re: SECTION A - Suggested Answers
Post by: slothpomba on October 31, 2010, 01:18:45 am

Haha my face was almost glued to the exam paper, trying to see if the line was on 0 or not for the heterozygous advantage question
Title: Re: SECTION A - Suggested Answers
Post by: stonecold on October 31, 2010, 01:20:48 am

Haha my face was almost glued to the exam paper, trying to see if the line was on 0 or not for the heterozygous advantage question

That wasn't actually necessary.  I was doing the same thing, then realised it couldn't have hit 0, because then it would never come back up.
Title: Re: SECTION A - Suggested Answers
Post by: stonecold on October 31, 2010, 01:21:20 am
man im tired... getting the exam was worth the wait :)
i think im on 23/25 good enough for me :D
thushan pls tell me 25/25 lol
good night guys.

so you going to declare thushan?  :P
Title: Re: SECTION A - Suggested Answers
Post by: cypriottiger on October 31, 2010, 01:24:31 am
so qn 1 was binary fission or wasnt? ( i dont have paper to check)
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 01:24:49 am
CBDDB BCCCD BAADB DCDDB ABACA

Yup it was binary fission
Title: Re: SECTION A - Suggested Answers
Post by: stonecold on October 31, 2010, 01:26:27 am
CBDDB BCCCD BAADB DCDDB ABACA

I mean you got full marks?

Yeah, Q1 is binary fission.

VCAA are so lame.  I could see through the paper and did that q before the exam even started :P
Title: Re: SECTION A - Suggested Answers
Post by: cypriottiger on October 31, 2010, 01:27:43 am
lol luckai! its lucky i didnt though, seeing a qn so easy as the first wouldve freaked me out when i got to the trickier ones
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 01:30:13 am
for MC i think so
Title: Re: SECTION A - Suggested Answers
Post by: stonecold on October 31, 2010, 01:30:46 am
for MC i think so


good stuff!
Title: Re: SECTION A - Suggested Answers
Post by: cypriottiger on October 31, 2010, 01:32:33 am
um i downloaded the exam but cant open it with special software crap :S any chance of getting it mediafired?
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 01:32:49 am
thanks man
you too?
Title: Re: SECTION A - Suggested Answers
Post by: stonecold on October 31, 2010, 01:33:09 am
just download winrar
Title: Re: SECTION A - Suggested Answers
Post by: stonecold on October 31, 2010, 01:33:48 am
thanks man
you too?

it seems so :D

I was really nervous about them, because I was always getting a few wrong in trials...
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 01:34:31 am
Nice. I bet you're going to get 75/75
Title: Re: SECTION A - Suggested Answers
Post by: cypriottiger on October 31, 2010, 01:36:04 am
hey quick SS calculation
im getting mid-A+ for SACs, midyear was A (one mark off A+) and im thinking end of year was 71/75. estimates?
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 01:38:44 am
71/75 would be an AMAZING effort

I say about a 45.
Title: Re: SECTION A - Suggested Answers
Post by: stonecold on October 31, 2010, 01:39:36 am
Nice. I bet you're going to get 75/75

Nah, there are some dodgy questions still, particularly:
-Centromere question.  Talked about mitosis and meiosis, and how the deletion of the centromere prevented attachment to the spindle fibres, reducing the chsm number which lead to humans
-Reason for birds dying.

-Reckon they will take both answers for the northern population, as long as you explained your reasoning.

And for questions with number answers, it was
-2/3 in Q1
-1/4 in the translocation question
-22 autosomes

?
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 01:43:15 am
For centromere qn i said something like:


•   Non-fused chromosomes and fused chromosomes are non-homologous so in a hybrid (containing both fused and   non-fused) cannot pair up during meiosis
•   This caused instant speciation and the divergence of the human line from the chimpanzee line

Birds dying - there'll be a variety of answers, as long as you back yourself up with evidence you'll be fine

The northern population - they might pay both

And yes it was 2/3, 1/4 and 22.
Title: Re: SECTION A - Suggested Answers
Post by: slothpomba on October 31, 2010, 01:43:33 am
Download PeaZip better than winrar...

I could also see through the paper lol

Havent counted but i think i might of gotten the full 25 on a casual glance  :D
Title: Re: SECTION A - Suggested Answers
Post by: cypriottiger on October 31, 2010, 01:45:33 am
Nice. I bet you're going to get 75/75

Nah, there are some dodgy questions still, particularly:
-Centromere question.  Talked about mitosis and meiosis, and how the deletion of the centromere prevented attachment to the spindle fibres, reducing the chsm number which lead to humans
-Reason for birds dying.

-Reckon they will take both answers for the northern population, as long as you explained your reasoning.

And for questions with number answers, it was
-2/3 in Q1
-1/4 in the translocation question
-22 autosomes

?

likewise, im taking 2 off for chromosome qn as a worst case scenario, i lost 1 in STR, lost 1 for autosome qn (said 21, took 1 off for sex chromosome). actually better make it 69/75, you never know where you'll lose those marks. new estimate?
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 01:48:14 am
44?
Title: Re: SECTION A - Suggested Answers
Post by: cypriottiger on October 31, 2010, 01:51:29 am
44?

sweettt lol thanks
Title: Re: SECTION A - Suggested Answers
Post by: crayolé on October 31, 2010, 04:07:03 am
MC was pretty much common sense I reckon. 25/25 from no work all semester

Fucked up SA though, probably no higher than 40-50
Title: Re: SECTION A - Suggested Answers
Post by: Stroodle on October 31, 2010, 08:31:14 am
woohoo. full marks on mc for me :)
Title: Re: SECTION A - Suggested Answers
Post by: sillysmile on October 31, 2010, 08:53:52 am
man im tired... getting the exam was worth the wait :)
i think im on 23/25 good enough for me :D
thushan pls tell me 25/25 lol
good night guys.
I got 24/25
the question I stuffed up was 2 haha..
for some reason I thought that the bull with horns was homozygous and would have only horned offspring, neglected that he may have been hetero.
Title: Re: SECTION A - Suggested Answers
Post by: sillysmile on October 31, 2010, 09:10:52 am
  I left 3 of the questions that I found the most difficult for the end, but managed to get get them all correct in 30 secs :)
Title: Re: SECTION A - Suggested Answers
Post by: lexitu on October 31, 2010, 10:42:57 am
Hey sorry guys for causing confusion with the few typos in my MC answers. It was late at night. They are all fixed now.

These were all of my answers on the exam proper except for question 24 so I think I got 24/25.
Title: Re: SECTION A - Suggested Answers
Post by: madoscar65 on October 31, 2010, 10:59:38 am
Just to make sure, how come short answer 1b is 2/3??? I got 1/2
Title: Re: SECTION A - Suggested Answers
Post by: jasoN- on October 31, 2010, 11:06:04 am
'heterozygous for the trait'
From the pedigree, it is known that she does not have the trait;
therefore she CANNOT have genotype 'aa' (if a is the allele for having the trait)
Thus by the punnet square, she could be either:
Aa, Aa, AA
hence 2/3 chance of heterozygous

dw, i got this answer wrong XD
Title: Re: SECTION A - Suggested Answers
Post by: onerealsmartass on October 31, 2010, 11:20:56 am
pretty chirpy this morning :)
worst case scenario ill get 63/75, best case i could get 68ish/75 just depends on what answers they are willing to take.
What would those marks be as a low/mid/high A+ if the A+ cut off is around 59-61??
Title: Re: SECTION A - Suggested Answers
Post by: pi on October 31, 2010, 11:26:29 am
pretty chirpy this morning :)
worst case scenario ill get 63/75, best case i could get 68ish/75 just depends on what answers they are willing to take.
What would those marks be as a low/mid/high A+ if the A+ cut off is around 59-61??


best case: 70, worst-case: 63

MC: 24/25

hopefully i get 40+ (should have done more than one practice exam mid-year though)
Title: Re: SECTION A - Suggested Answers
Post by: mistahcee on October 31, 2010, 11:28:07 am
what scores out of 150 in the midyear did all of you get?
Title: Re: SECTION A - Suggested Answers
Post by: onerealsmartass on October 31, 2010, 11:30:07 am
cant quite remember but whatever was required for a B+ around 103 or something... quite sad.

Title: Re: SECTION A - Suggested Answers
Post by: pi on October 31, 2010, 11:30:38 am
i didnt check, but I got an A, probably 117-ish

i should have studied
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 11:37:14 am
137 in midyear

i'm hoping for 144+ in end of year
Title: Re: SECTION A - Suggested Answers
Post by: onerealsmartass on October 31, 2010, 11:46:25 am
Thushan quick study score prediction please (:
Mid yr: B+ high
SACS: 187.5/200 rank 5~ (3 A+ in md yr)
End of YR: A+ ( what if i get 64/75 and 67/75)
Thanks
Title: Re: SECTION A - Suggested Answers
Post by: pi on October 31, 2010, 11:46:43 am
137 in midyear

i'm hoping for 144+ in end of year

that has to be at least 49. AK was right, you are a genius


btw, doubt you would be happy with 45+ in either bio or methods (how many marks have you dropped in methods SACS, probable <2). you need to change those predictions
Title: Re: SECTION A - Suggested Answers
Post by: lexitu on October 31, 2010, 11:54:17 am
Thushan quick study score prediction please (:
Mid yr: B+ high
SACS: 187.5/200 rank 5~ (3 A+ in md yr)
End of YR: A+ ( what if i get 64/75 and 67/75)
Thanks

~37 I think.
Title: Re: SECTION A - Suggested Answers
Post by: onerealsmartass on October 31, 2010, 12:06:00 pm
yeah 37 is the minimum i want :)
Title: Re: SECTION A - Suggested Answers
Post by: lexitu on October 31, 2010, 12:13:25 pm
Haha yeah awesome. Your estimate is about right. All the best :) What are you hoping to do in 2012?
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 12:22:04 pm
With 64 i'd say 38
With 67 i'd say 39-40 - biology is weird like that; a 67 is an extremely high score in bio
Title: Re: SECTION A - Suggested Answers
Post by: onerealsmartass on October 31, 2010, 12:32:36 pm
thanks thushan, hopeful for anything above 38, happy with a 37 or 38.

Umm not too sure atm, still looking into different courses. Ultimate aim would be Med, if i still want to continue down that path then maybe BioMed.
I like the sound of Dentisry - very good pay :P , Pharmacy wouldnt be too bad. In general something to do with science/health.
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 12:40:21 pm

that has to be at least 49. AK was right, you are a genius


btw, doubt you would be happy with 45+ in either bio or methods (how many marks have you dropped in methods SACS, probable <2). you need to change those predictions

thanks man, but it'd kind of look cocky if i put Biology [50] and Maths Methods [50] as my goals in my sig, and I could really be owned if I say drop half a mark in the methods exam
Title: Re: SECTION A - Suggested Answers
Post by: onerealsmartass on October 31, 2010, 12:48:19 pm
trying not drop many marks in further is gonna be a killer....
Title: Re: SECTION A - Suggested Answers
Post by: simpak on October 31, 2010, 01:10:13 pm
Lawl trust me getting a 50 in Bio is easy.
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 01:46:24 pm
If you say so, but given that this exam was relatively easy, i'll probably need 148+ to get a 50, given I got 137 in unit 3 and 198 (rank 1) out of 200 in a school where about 16 people (~27%) got A+ :S
Title: Re: SECTION A - Suggested Answers
Post by: pi on October 31, 2010, 03:23:11 pm
If you say so, but given that this exam was relatively easy, i'll probably need 148+ to get a 50, given I got 137 in unit 3 and 198 (rank 1) out of 200 in a school where about 16 people (~27%) got A+ :S

around 16 people in my class (of 25) alone got A+last time, more this time I think

Title: Re: SECTION A - Suggested Answers
Post by: simpak on October 31, 2010, 05:20:07 pm
Got 140 in Exam 1, 138 in Exam 2 and 25% above class average for SACs.
Title: Re: SECTION A - Suggested Answers
Post by: simpak on October 31, 2010, 05:21:43 pm
And another girl in my class got a 50 as well.
We just had a really good teacher, to be honest.  She really knew her stuff (Checkpoints author).
She would hold extra classes in lunch times and stuff, give up all her spare time to teach us and correct our exams and meet with us outside of class.
I honestly think that's a major part of why I did well.
That and I went to a private school, so cohort - everyone cared.
Title: Re: SECTION A - Suggested Answers
Post by: ivslt247 on October 31, 2010, 05:27:15 pm
can someone explain to me 24? i thought it was homology cause the diagram shows us they diverged from the same ancestor =_=
Title: Re: SECTION A - Suggested Answers
Post by: onerealsmartass on October 31, 2010, 05:32:12 pm
yeah, i did the same but they diverged a long time ago. like thushan said at the kingdom stage and it clearly says they use the flagella for locomotion or something therefore analagous..
Title: Re: SECTION A - Suggested Answers
Post by: pi on October 31, 2010, 05:32:57 pm
i wrote convergent... fail
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 05:35:25 pm
convergent was the correct answer lol
Title: Re: SECTION A - Suggested Answers
Post by: pi on October 31, 2010, 05:38:46 pm
wtf? really! awesome 25/25
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 05:39:43 pm
And another girl in my class got a 50 as well.
We just had a really good teacher, to be honest.  She really knew her stuff (Checkpoints author).
She would hold extra classes in lunch times and stuff, give up all her spare time to teach us and correct our exams and meet with us outside of class.
I honestly think that's a major part of why I did well.
That and I went to a private school, so cohort - everyone cared.

Wow that's nice

Yeah I go to a private school as well, but my teacher is not the greatest, although he really puts in a lot of effort - my cohort is quite strong as well.

Also, this unit 4 exam was quite easy compared to last year, so a 138 this year would not cut it for me (you would have gotten probably 147-150 had you done this year's paper).
Title: Re: SECTION A - Suggested Answers
Post by: simpak on October 31, 2010, 05:52:00 pm
And another girl in my class got a 50 as well.
We just had a really good teacher, to be honest.  She really knew her stuff (Checkpoints author).
She would hold extra classes in lunch times and stuff, give up all her spare time to teach us and correct our exams and meet with us outside of class.
I honestly think that's a major part of why I did well.
That and I went to a private school, so cohort - everyone cared.

Wow that's nice

Yeah I go to a private school as well, but my teacher is not the greatest, although he really puts in a lot of effort - my cohort is quite strong as well.

Also, this unit 4 exam was quite easy compared to last year, so a 138 this year would not cut it for me (you would have gotten probably 147-150 had you done this year's paper).

I still haven't had a chance to look at the paper.
But thanks for the vote of confidence there :3 it's nice to know you think I am so academically inclined, I AM FLATTERED!
Anyway, I seriously think anyone on this board is capable of getting a 50 in Biol - I know last year's second year exam was comparatively harder compared to some others but I never expected to open up my results at 7am on December 14 and see a perfect score.
Let alone anything over 99.

Was literally expecting around 85 for my ENTER, preparing to rep Monash Journalism or Latrobe Journo.
Went to those 'after you get your ENTER' info sessions and it was the first time I had seriously considered being able to get into Law.
Everyone around me was asking questions about alternative pathways, and I still didn't believe it haha.

Anyway, I have faith in you all - I think this years class is very good at Biology.
A lot of you know more than I do.
But then I haven't done Biol properly aside from tutoring in 12 months...so I suppose I am excused from my failures in some ways.
Title: Re: SECTION A - Suggested Answers
Post by: happyhappyland on October 31, 2010, 05:57:48 pm
I think the paper had quite alot of tricky parts to it.. for 2006-2009 exams i guessed 10 or so marks for short answer and still for 2010 I guessed around 8 marks (guess as in an educated guess an answer that im not 100% that im correct). Thats why I dont think the paper was easy as everyone seems to think it was. I mean multiple choice was relatively easy, but the short answer might not have posed a challenged, but there are certain areas that marks can be easily deducted without knowing
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 06:02:17 pm
Yeah 2009 was relatively tougher, which explains the following story:

This person in my school was expected to get a 50 at the start of the year last year. Does decently in SACs and then goes into the Unit 3 exam. Gets a statement of marks, and DAMN - he got 126 (A+ was 120). So his hopes for a 50 were dashed.

He was really good at unit 4, his SACs were again decent, he didn't put that much effort into unit 4 study because he knew the content and thought - well, my unit 3 was bad. Goes into unit 4 exam, does it.

Results day comes.

Did I say that his hopes were dashed? He ended up getting a 50. He came out of nowhere.

Explanation? He got 147 in the unit 4 exam without studying.

Moral: Biology is unpredictable.
Title: Re: SECTION A - Suggested Answers
Post by: pi on October 31, 2010, 06:08:13 pm
that's awesome. did u tell AK, he was really depressed after unit 3...


I'll be happy with 40+
Title: Re: SECTION A - Suggested Answers
Post by: simpak on October 31, 2010, 06:13:15 pm
Lol I remember I typo'd my marks when we had the thread last year and I wrote I had A+ A+ A and nobody would believe me and then I realised I had typo'd.
But that's amazing!
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 06:16:52 pm
that's awesome. did u tell AK, he was really depressed after unit 3...


I'll be happy with 40+

I drummed it into him after I found out
Title: Re: SECTION A - Suggested Answers
Post by: pi on October 31, 2010, 06:17:45 pm
that's awesome. did u tell AK, he was really depressed after unit 3...


I'll be happy with 40+

I drummed it into him after I found out

good one
Title: Re: SECTION A - Suggested Answers
Post by: s2lindah on October 31, 2010, 06:47:19 pm
Far out... Did I just choose a tRNA strand with a T... LOL damn exam nerves.
All the other answers seem good :)
Title: Re: SECTION A - Suggested Answers
Post by: pi on October 31, 2010, 06:50:44 pm
Far out... Did I just choose a tRNA strand with a T... LOL damn exam nerves.
All the other answers seem good :)

i nearly did that, changed it in last ten mins during revision
Title: Re: SECTION A - Suggested Answers
Post by: onerealsmartass on October 31, 2010, 07:03:09 pm
haha really? as soon as i read tRNA i crossed out all the T's :)
i did a question like this a couple of nights before, and i did it the long way cos i realised i should have crossed out all the options with T :P
Title: Re: SECTION A - Suggested Answers
Post by: Russ on October 31, 2010, 07:17:09 pm
So I had a pretty full on day, but does anybody want to see my answers for the questions I did?
(ie none of the evolution ones)
Title: Re: SECTION A - Suggested Answers
Post by: Jdog on October 31, 2010, 07:22:46 pm
theres a mistake in the paper

for the questoin where ou had to provide the complementary Anticodon molecule

In the question it states, "A DNA template strand codes for the amino acid serine with any of the following Codons."

should be triplets..


IF YOU TELL YOUR TEACHER AND THEY RING UP VCAA EVERYONE WILL GET THE MARK .
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 07:34:07 pm
LOL! Nice Jdog!
Title: Re: SECTION A - Suggested Answers
Post by: thushan on October 31, 2010, 07:47:23 pm
So I had a pretty full on day, but does anybody want to see my answers for the questions I did?
(ie none of the evolution ones)

Yes - much appreciated
Title: Re: SECTION A - Suggested Answers
Post by: Russ on October 31, 2010, 08:55:34 pm
Only has half of them, you answers are better than mine for the last half because I don't study evolution (hence why I tend to deflect questions about it when people ask me ;) )

The meiosis question was a bitch, I haven't had to know the stages for a long time
Title: Re: SECTION A - Suggested Answers
Post by: lexitu on October 31, 2010, 09:10:31 pm
theres a mistake in the paper

for the questoin where ou had to provide the complementary Anticodon molecule

In the question it states, "A DNA template strand codes for the amino acid serine with any of the following Codons."

should be triplets..


IF YOU TELL YOUR TEACHER AND THEY RING UP VCAA EVERYONE WILL GET THE MARK .


Nah, it's no mistake, VCAA call triplets codons. http://www.vcaa.vic.edu.au/vce/studies/biology/biologyfaqs.html


---- Thanks for doing that Russ :)
Title: Re: SECTION A - Suggested Answers
Post by: Jdog on October 31, 2010, 09:20:43 pm
what? i thought codons only referred to m rna Triplets for DNA, and anticodons for t rna
Title: Re: SECTION A - Suggested Answers
Post by: onerealsmartass on October 31, 2010, 09:45:28 pm
what? i thought codons only referred to m rna Triplets for DNA, and anticodons for t rna
thats what i memorised...
Title: Re: SECTION A - Suggested Answers
Post by: Jdog on October 31, 2010, 09:47:40 pm
i dont mind what they do to be honest, cuz i got the answer right,

only the selfish side of me doesn't want the rest of the state to get a mark so that cutoofs go just that much higher.
Title: Re: SECTION A - Suggested Answers
Post by: onerealsmartass on October 31, 2010, 09:48:44 pm
hhaha yeah good point. its good for us cos we got it right :D
Title: Re: SECTION A - Suggested Answers
Post by: cypriottiger on October 31, 2010, 10:23:48 pm
haha yay turns out i did get the autosome qn right! sorry peeps, just super excited :) for some reason memorised the question so that my answer was 21 (44 autosomes in somatic, how many in gamete? i put 22-1 sex = 21)

hmm so that brings me to 73/75 maximum so far... but this excludes chromosome/fish qn
Title: Re: SECTION A - Suggested Answers
Post by: Caspar on October 31, 2010, 11:04:41 pm
I thuoght Q1 was binary fission :( fml

Far out, you made my heart stop for a second :P.
Title: Re: SECTION A - Suggested Answers
Post by: pi on November 01, 2010, 10:45:33 am
haha yay turns out i did get the autosome qn right! sorry peeps, just super excited :) for some reason memorised the question so that my answer was 21 (44 autosomes in somatic, how many in gamete? i put 22-1 sex = 21)

hmm so that brings me to 73/75 maximum so far... but this excludes chromosome/fish qn


damn, i put 22

my reasoning: 46 chromosomes in a somatic, 23 in haploid gamete, therefore 23-1=22 autosomes
Title: Re: SECTION A - Suggested Answers
Post by: thushan on November 01, 2010, 10:50:36 am
I got 22 as well

23 chromosomes in a sex gamete, and 1 of them is an X OR a Y
Title: Re: SECTION A - Suggested Answers
Post by: Russ on November 01, 2010, 11:12:36 am
The answer is 22.
(it was a concept check question for my lecture last week)
Title: Re: SECTION A - Suggested Answers
Post by: pi on November 01, 2010, 11:21:26 am
I got 22 as well

23 chromosomes in a sex gamete, and 1 of them is an X OR a Y

awesome, did Scotch give u guys a day off as well?
Title: Re: SECTION A - Suggested Answers
Post by: thushan on November 01, 2010, 11:26:43 am
mhm
Title: Re: SECTION A - Suggested Answers
Post by: Stroodle on November 01, 2010, 11:34:01 am
haha yay turns out i did get the autosome qn right! sorry peeps, just super excited :) for some reason memorised the question so that my answer was 21 (44 autosomes in somatic, how many in gamete? i put 22-1 sex = 21)

hmm so that brings me to 73/75 maximum so far... but this excludes chromosome/fish qn

Why'd you subtract one from the 22 autosomes? You already subtracted the sex chromosomes at the start, giving you 44 autosomes.
Title: Re: SECTION A - Suggested Answers
Post by: Jdog on November 01, 2010, 12:15:10 pm
yeah defs 22,


sorry to burst your bubble..
Title: Re: SECTION A - Suggested Answers
Post by: cypriottiger on November 01, 2010, 03:24:00 pm
oh sorry you misunderstood me
i thought my answer was 21, but it was 22 which is the correct one :)
Title: Re: SECTION A - Suggested Answers
Post by: thushan on November 01, 2010, 03:34:51 pm
So apart from the centromere question, how were the rest of my suggested solutions?
Title: Re: SECTION A - Suggested Answers
Post by: Russ on November 01, 2010, 03:48:24 pm
They were good. Couple of minor points but I think that's more a product of the VCE syllabus than being incorrect.
Title: Re: SECTION A - Suggested Answers
Post by: thushan on November 01, 2010, 03:51:54 pm
Oh really, thanks! What were the minor points, just out of interest?
Title: Re: SECTION A - Suggested Answers
Post by: pi on November 01, 2010, 03:54:52 pm
Oh really, thanks! What were the minor points, just out of interest?

perfectionist... (its a good thing)
Title: Re: SECTION A - Suggested Answers
Post by: Russ on November 01, 2010, 03:57:20 pm
^^
haha lol

From memory the mRNA moving "into" the ribosome and the explanation for the 1/4 gamete question.
But they were impressive answers, I couldn't write answers that good for my subjects
Title: Re: SECTION A - Suggested Answers
Post by: thushan on November 01, 2010, 03:58:54 pm
Yeah I know about those points - the two subunits of the ribosome form around the mRNA
Thing is, I could have gone on a full explanation about independent assortment of homologous pairs of chromosomes and all, but they gave two lines only to explain!
Title: Re: SECTION A - Suggested Answers
Post by: pi on November 01, 2010, 04:06:35 pm
Yeah I know about those points - the two subunits of the ribosome form around the mRNA
Thing is, I could have gone on a full explanation about independent assortment of homologous pairs of chromosomes and all, but they gave two lines only to explain!

that was the only question i had no idea about
Title: Re: SECTION A - Suggested Answers
Post by: thushan on November 01, 2010, 04:09:05 pm
Wow you got the centromere question!? That's awesome

Hey Russ would I get 0 or 1 out of 2 for that qn?
Title: Re: SECTION A - Suggested Answers
Post by: Russ on November 01, 2010, 04:12:01 pm
Which question?
The VCAA will give you the marks for the meiosis one, it really shouldn't have been on there from what I know of the study design
Title: Re: SECTION A - Suggested Answers
Post by: thushan on November 01, 2010, 04:14:19 pm
•   Non-fused chromosomes and fused chromosomes are non-homologous so in a hybrid (containing both fused and non-fused) cannot pair up during meiosis (1)
•   This caused instant speciation and the divergence of the human line from the chimpanzee line (1)

Why is the inactivation of one of the centromeres a significant point of human evolution?

Title: Re: SECTION A - Suggested Answers
Post by: cypriottiger on November 01, 2010, 04:17:15 pm
hmm my answer is based around:
1. the inability of the cell to divide properly during mitosis, resulting in a mutant hybrid
2. the formation of a proper chromosome allowed for mating between two hybrids, as homologous chromosomes could pair during zygote formation ie. sterility is eliminated, a new species formed.
mark distribution?
Title: Re: SECTION A - Suggested Answers
Post by: pi on November 01, 2010, 04:17:25 pm
Wow you got the centromere question!? That's awesome

Hey Russ would I get 0 or 1 out of 2 for that qn?

had an idea about that one, but the idea was wrong...

i just said that: the fused chromosome with one centromere active would allow for mitosis/meiosis to occur, allowing it to be passed on to future generations. If it had two centromeres, it would not be able to do this, and therefore have no effect on evolution.

 
Title: Re: SECTION A - Suggested Answers
Post by: Russ on November 01, 2010, 04:20:50 pm
Probably 1 mark. Don't see them giving 0 for that, it was a decent answer (to an ordinary question)
Title: Re: SECTION A - Suggested Answers
Post by: pi on November 01, 2010, 04:22:56 pm
Probably 1 mark. Don't see them giving 0 for that, it was a decent answer (to an ordinary question)

very ordinary question, does it even fit on the study design properly?
Title: Re: SECTION A - Suggested Answers
Post by: thushan on November 01, 2010, 04:23:46 pm
woo! so if VCAA doesn't kill us i'd be sitting on 148 :D
Title: Re: SECTION A - Suggested Answers
Post by: cypriottiger on November 01, 2010, 04:24:00 pm
Probably 1 mark. Don't see them giving 0 for that, it was a decent answer (to an ordinary question)

very ordinary question, does it even fit on the study design properly?

its the bullshit question next year's yr 12s will be bitchng about when they do our exam as a trial ;)
Title: Re: SECTION A - Suggested Answers
Post by: thushan on November 01, 2010, 04:25:03 pm
LOL yeah

Hey Russ what did you get in bio when you did it? Study scores and individual GAs (out of 75 and 200)?
Title: Re: SECTION A - Suggested Answers
Post by: pi on November 01, 2010, 04:25:50 pm
woo! so if VCAA doesn't kill us i'd be sitting on 148 :D

WOW! i hope I can get 136-140
Probably 1 mark. Don't see them giving 0 for that, it was a decent answer (to an ordinary question)

very ordinary question, does it even fit on the study design properly?

its the bullshit question next year's yr 12s will be bitchng about when they do our exam as a trial ;)

true that
Title: Re: SECTION A - Suggested Answers
Post by: Russ on November 01, 2010, 04:28:17 pm
LOL yeah

Hey Russ what did you get in bio when you did it? Study scores and individual GAs (out of 75 and 200)?

I never did biology at high school (and thus had a fantastic 1st year of uni having to learn it all in a semester)
Title: Re: SECTION A - Suggested Answers
Post by: Jdog on November 01, 2010, 06:04:26 pm
for the questioin about the northern population of mussels, do you guys think that , we could have said the thickness of the shell would have been constant since they weren't exposed to the selective agent ofthe Crab.

and i thought mussels were stuck to rocks, how would gene flow occur, maybe their gamets would float through water?


Title: Re: SECTION A - Suggested Answers
Post by: pi on November 01, 2010, 07:04:26 pm
for the questioin about the northern population of mussels, do you guys think that , we could have said the thickness of the shell would have been constant since they weren't exposed to the selective agent ofthe Crab.

and i thought mussels were stuck to rocks, how would gene flow occur, maybe their gamets would float through water?





that is what I wrote (without the mussel sex confusions), but it is probably wrong or maybe one mark only
Title: Re: SECTION A - Suggested Answers
Post by: stonecold on November 01, 2010, 07:11:10 pm
for the questioin about the northern population of mussels, do you guys think that , we could have said the thickness of the shell would have been constant since they weren't exposed to the selective agent ofthe Crab.

and i thought mussels were stuck to rocks, how would gene flow occur, maybe their gamets would float through water?





that is what I wrote (without the mussel sex confusions), but it is probably wrong or maybe one mark only

I think this is still right.

My volcano theory is wrong, but it is reasonable to assume they will remain constant.

If gene flow was occurring, then the northern shell mussel population would have increased in size too, and likely have been a similar size to the southern population.

Moreover, the population would be massive, so genetic drift wouldn't really apply.
Title: Re: SECTION A - Suggested Answers
Post by: pi on November 01, 2010, 07:15:01 pm
for the questioin about the northern population of mussels, do you guys think that , we could have said the thickness of the shell would have been constant since they weren't exposed to the selective agent ofthe Crab.

and i thought mussels were stuck to rocks, how would gene flow occur, maybe their gamets would float through water?





that is what I wrote (without the mussel sex confusions), but it is probably wrong or maybe one mark only

I think this is still right.

My volcano theory is wrong, but it is reasonable to assume they will remain constant.

If gene flow was occurring, then the northern shell mussel population would have increased in size too, and likely have been a similar size to the southern population.

Moreover, the population would be massive, so genetic drift wouldn't really apply.

hope your theory is right
Title: Re: SECTION A - Suggested Answers
Post by: thushan on November 01, 2010, 07:15:15 pm
Hmm, not really...the shell thickness would not increase nearly as much as on the southern population, as gene flow is (in this case) nowhere near as powerful at changing allele frequencies as selection.

Anyway, let's see what VCAA says.
Title: Re: SECTION A - Suggested Answers
Post by: Jdog on November 01, 2010, 07:57:26 pm
if you were to mention gene flow had occured, you have to say that the increase in size was only minor, however i think thye will except both answers, if either is backed up with statements about the lack/presence of gene flow.
Title: Re: SECTION A - Suggested Answers
Post by: thushan on November 01, 2010, 08:16:45 pm
I think I said slightly in my answer
Title: Re: SECTION A - Suggested Answers
Post by: cjudd3votes on November 03, 2010, 08:48:23 pm
Any chance of a SS estimate? Ranked first in cohort for SACs, 137/150 midyear and thinking 71/75 unit 4 :\ hoping high 40s :s
Title: Re: SECTION A - Suggested Answers
Post by: cypriottiger on November 03, 2010, 09:10:04 pm
well ive heard that you can get a 50 in bio so long as you lose less then 12 marks on both exams. you've lost 10.5 if ur unit 4 score is accurate, so i guess with med-high A+ on sacs you should be in line for a 50 :o congrats! but id get second reference if i were you
Title: Re: SECTION A - Suggested Answers
Post by: cjudd3votes on November 03, 2010, 09:15:58 pm
 :o Didn't think I'd be in line for a 50.. was thinking 47/48 but I'd be rapt with a 50!

And just a point on the mussel shell thickness, would it be safe to say that increased competition forced other species that consumed the mussels to move north and thus the thickness of the northern population would increase?  :-\
Title: Re: SECTION A - Suggested Answers
Post by: Jdog on November 03, 2010, 09:42:33 pm
i don't know, if mussels can move on purpose?  i don't really know.
Title: Re: SECTION A - Suggested Answers
Post by: cypriottiger on November 03, 2010, 09:46:07 pm
umm thats kind of making the assumption that the mussel's knew north was safe....
Title: Re: SECTION A - Suggested Answers
Post by: cjudd3votes on November 03, 2010, 09:52:27 pm
No the mussels didn't move, other species that ATE mussels moved north because there were fewer thin shelled mussels in the southern region.
Title: Re: SECTION A - Suggested Answers
Post by: thushan on November 03, 2010, 10:30:39 pm
Nice work on your unit 3 and 4 exams cjudd3votes - and cypriottiger is right, you'll be in for a 50

As far as that gene flow question is concerned, it said in the stem that the crabs were unable to move into the northern population (reason was not given)...so I don't think they would pay that sorry :S
Title: Re: SECTION A - Suggested Answers
Post by: Jdog on November 04, 2010, 08:39:58 am
yeah, it said specificically that, the crabs were unable to move past the border.

Don't fret though, thats only two marks, im sure youll still get 71.

i think the two answers they will pay are :

no change, due to selective agent

change, due to gene flow.
Title: Re: SECTION A - Suggested Answers
Post by: cjudd3votes on November 04, 2010, 08:46:55 am
I think this is hard to explain over the internet :-\ species other than the introduced sand crab could potentially consume the southern mussels. When the new crab species is introduced, other species which previously consumed thin-shelled mussels were forced to migrate in search of thinner shells. Hence, other species that eat mussels move north, eat predominantly thin-shelled northern mussels which gives the thick shelled mussels the selective advantage. I'm not too fussed, I just wanted over 47 :) I'm more used to chemistry style marking where you can get 95% on an exam and still be well out of contention for a 50   :buck2:
Title: Re: SECTION A - Suggested Answers
Post by: thushan on November 04, 2010, 08:52:29 am
Fair enough, although that is a bit of a stretch....

And yeah, is chem like methods where if you get like 100% after moderation in SACs and then drop 0.5 marks over both exams you're bumped down to a 49?
Title: Re: SECTION A - Suggested Answers
Post by: Jdog on November 04, 2010, 09:10:34 am
Maybe,

I think your adding new infrmation that wasn't in the question thought , thats my only problem.
Title: Re: SECTION A - Suggested Answers
Post by: stonecold on November 04, 2010, 09:18:57 am
:o Didn't think I'd be in line for a 50.. was thinking 47/48 but I'd be rapt with a 50!

And just a point on the mussel shell thickness, would it be safe to say that increased competition forced other species that consumed the mussels to move north and thus the thickness of the northern population would increase?  :-\

epic user name!!!
Title: Re: SECTION A - Suggested Answers
Post by: cjudd3votes on November 04, 2010, 09:55:51 am
epic user name!!!
The finest!

And yeah, is chem like methods where if you get like 100% after moderation in SACs and then drop 0.5 marks over both exams you're bumped down to a 49?

Yeah, in chem I dropped 3 marks I think? And because it was an easy paper, can't get a 50 now, so hoping for 45+ in that :) Not too sure how you'd you dropping 1/2 mark on each, but I reckon you'd definately be a 49 if not 50. And yeah again on the bio question, doesn't matter that much, only a couple of marks :)
Didn't realise how competitive methods was until a couple of weeks ago; even with some decent marks you'd only be around 43/44. Times like this I wish I was good at a language.

Title: Re: SECTION A - Suggested Answers
Post by: stonecold on November 04, 2010, 10:06:57 am
epic user name!!!
The finest!

And yeah, is chem like methods where if you get like 100% after moderation in SACs and then drop 0.5 marks over both exams you're bumped down to a 49?

Yeah, in chem I dropped 3 marks I think? And because it was an easy paper, can't get a 50 now, so hoping for 45+ in that :) Not too sure how you'd you dropping 1/2 mark on each, but I reckon you'd definately be a 49 if not 50. And yeah again on the bio question, doesn't matter that much, only a couple of marks :)
Didn't realise how competitive methods was until a couple of weeks ago; even with some decent marks you'd only be around 43/44. Times like this I wish I was good at a language.



I reckon full marks on chem exam 2 might get us a 48.  which imo is a lot easier than methods, particularly exam 2...