General Thoughts: Biology (2 Viewers)

[jensymalone]

Overall i found the test relatively esay, although the mutliple choice were particuarly challenging (if anyone has the answers that would be great). I was a bit annoyed with the hearing question whiched asked for three different types of mammals - i had researched 3 animals, but only one of them was mammal. I was also underprepared for the DNA structure question but i think i managed to BS enough to get 3 marks.

 

[OmmU]

Re: 2011 HSC Biology Paper

if its B and b, then the kids would be BB, Bb, Bb and bb, as seen in the diagram..
however conventionally different sized letters relate to a dominant/recessive trait.
Therefore BB, Bb and Bb were also display the same phenotype - but if you look at the pedigree, this is not supported, thus its D, in which the traits are AB - and thus co dominant.

That, I almost put A but realised the parents had to have the same genotype xD Silly me Good thing I picked it up though.

 

[Dylanamali]

My friend, who was sitting in front of me (annoying the shit out of me with all the extra booklets he used. I only used 4) probably got 17 in MC, full marks in the rest. He has Economics now too. State rank right there.

wtf how many extra booklets =/,
do you guys right big or what..
i ended up using 3 extra booklets.
do you write on the whole page of the space for the answers, or do you only write on the lines provided?

 

[1981Grant]

gg state rank, right here.
top 10 school?

Yeah, we're ranked 7th at the moment. I don't know if we'll go up and down after this year though. I might have lost more for core though, just depends how hard the marker is, even though my answers were pretty much solid for everything.

I definitely won't get a state ranking though, there's people so much better than me at my school. I was ranked 5/55ish at the start of the year but had to ease off to fix up my other subjects.

 

[Riproot]

I kept alternating between Cytotoxic and Killer T's, then eventually chose killer T cells >_< I was always taught that they were exactly the same.

ME too!!!
And I also thought that the Chromosomes one needed to be more specific than just DNA + other stuff, so I put A. -_-

 

[m-swan]

SAME! i thought it was a trick so i put b-cells but i dono it just confused m :/

 

[piraterawr]

MC Q17. Why D? C seems more correct to me because of the use of both capitals, showing dominant, and lowercase showing recessive. Instead of D in which both parents were heterozygous with two dominent genes? Very similar answers though. Just want to know why D was picked. Other than that 18-19/20.

 

[Riproot]

Overall i found the test relatively esay, although the mutliple choice were particuarly challenging (if anyone has the answers that would be great). I was a bit annoyed with the hearing question whiched asked for three different types of mammals - i had researched 3 animals, but only one of them was mammal. I was also underprepared for the DNA structure question but i think i managed to BS enough to get 3 marks.

Check 2nd post in this thread. Two answers are wrong.
Yeah, I made my animals up on the spot. :/

wtf how many extra booklets =/,
do you guys right big or what..
i ended up using 3 extra booklets.
do you write on the whole page of the space for the answers, or do you only write on the lines provided?

He writes normal sized and I write a bit bigger but I would've needed the extra room regardless.
I did half a page extra for a few 2-3 markers, 2.5 pages extra for the 7 marker in Section I B and 3 extra pages for the communication 7 marker

 

[Riproot]

MC Q17. Why D? C seems more correct to me because of the use of both capitals, showing dominant, and lowercase showing recessive. Instead of D in which both parents were heterozygous with two dominent genes? Very similar answers though. Just want to know why D was picked. Other than that 18-19/20.

Co-Dominance. That's why there are three separate phenotypes.

 

[caityj]

The MC killed me, which was disappointing because I've been getting 19/20 on most practice papers. I think I got 15/20.

I said the reptile study was inaccurate because it didn't take into account behavioural adaptations (basking in sun in morning/afternoon and shade in the middle of the day, etc) as they were locked in small cages, would that get me marks?

Also I had no idea about the number for sound so I talked about the different habits and different structures for hearing and how hearing was used, how many marks do you think I'll lose for that?

 

[Dylanamali]

Check 2nd post in this thread. Two answers are wrong.
Yeah, I made my animals up on the spot. :/

He writes normal sized and I write a bit bigger but I would've needed the extra room regardless.
I did half a page extra for a few 2-3 markers, 2.5 pages extra for the 7 marker in Section I B and 3 extra pages for the communication 7 marker

wow 1 page, for a 2/3 marker.. overkill much? hahaha
nah it's good.. others in my class finished with like an hour to spare.. I ended up finishing just as the examiner said put pens down, coz I wrote so much.

 

[Dylanamali]

The MC killed me, which was disappointing because I've been getting 19/20 on most practice papers. I think I got 15/20.

I said the reptile study was inaccurate because it didn't take into account behavioural adaptations (basking in sun in morning/afternoon and shade in the middle of the day, etc) as they were locked in small cages, would that get me marks?

Also I had no idea about the number for sound so I talked about the different habits and different structures for hearing and how hearing was used, how many marks do you think I'll lose for that?

3 for the values/ranges, 3 for the reasons + comparison

 

[snorelacks]

With the MC, is killer T cells same as cytotoxic T cells? I mean the way I learnt it at school we called it killer T...

 

[damo_g]

MC Q17. Why D? C seems more correct to me because of the use of both capitals, showing dominant, and lowercase showing recessive. Instead of D in which both parents were heterozygous with two dominent genes? Very similar answers though. Just want to know why D was picked. Other than that 18-19/20.

There were 3 phenotypes in the next generation. C only showed two possible phenotypes where D showed 3.

 

[nephh22]

Re: 2011 HSC Biology Paper

Multiple Choice: http://sixpop.com/files/21/Bio MC.pdf
MC Q10 -12: http://sixpop.com/files/21/photo 1.JPG
& Q16-17: http://sixpop.com/files/21/photo 2.JPG

They were my answers so don't rely on them Sorry for the poor quality.

Options: http://sixpop.com/files/21/Bio Options.pdf

Again not great quality, if someone scans them then please post the link xD

according to ur answers, i got 17/20 for multiple choice... question 8 - please explain to me the difference between killer T and cytotoxic T cells: i thought they were the same >_<

 

[Riproot]

Re: 2011 HSC Biology Paper

you seem to have done preety well in MC's riproot IMO 18/20, according to my results, but maybe 17/20 according to others..
I think question 8 was a little dodgy.. asking students to differentiate between killer T cells and cytotoxic T cells..

SO DID I!
And the fucking structure one... I fucking knew it! I looked at my notes just before I went in, and I was like, nahhhh it has to be more specific, and there are way too many Bs. :/

 

[piraterawr]

Co-Dominance. That's why there are three separate phenotypes.

There were also three results for C, though. 25%:50%:25% for both C and D. Plus, you wouldn't be able to tell whether A and B in D were co-dominant or anything, so it could be wrong to just assume they mean AB was co-domiant because we weren't told information like that. Also, I figured with co-domiance, the 'tree' we were given would have shown similarities if that was the case instead of being completely different in colour/whatever. But IDK. I hate those things. Edit: Ah, wait, I can see it now. Bb would have showed the same characteristics as BB. -facepalm-

 

[1981Grant]

MC Q17. Why D? C seems more correct to me because of the use of both capitals, showing dominant, and lowercase showing recessive. Instead of D in which both parents were heterozygous with two dominent genes? Very similar answers though. Just want to know why D was picked. Other than that 18-19/20.

D is correct because you needed to realise that the cross was co dominant. You would have realised the codominance as there was three different phenotypes (not three different genotypes), the capital letters represented dominant genes. The co-dominance result in three different phenotypes that way: AA, AB, BB

 

[piraterawr]

Then, 18/20 for MC. Messed up killer/cytotoxic and the damn tree. :C Think I lost 4 - 5 marks in Section 2. And thinking 1 mark at the most in Communication. I'm all good.

 

[bigbirdbanana]

There were also three results for C, though. 25%:50%:25% for both C and D. Plus, you wouldn't be able to tell whether A and B in D were co-dominant or anything, so it could be wrong to just assume they mean AB was co-domiant because we weren't told information like that. Also, I figured with co-domiance, the 'tree' we were given would have shown similarities if that was the case instead of being completely different in colour/whatever. But IDK. I hate those things. Edit: Ah, wait, I can see it now. Bb would have showed the same characteristics as BB. -facepalm-

PHENOtypes not GENOtypes, aka 3 different things expressed, not merely three different genetic compositions. In normal dominance/recession there are only two phenotypes (homozygous dominant and heterozygous both show the same phenotype), whilst in co-dominance there are three, as there is homozygous for both letters, ie AA and BB, but also the co-dominant heterozygous form, AB.