HSC Biology Question Thread

[KT Nyunt]

The mRNA complement of TACCTTGTACCC would be:
CUGGAACAUGGG.

Careful - That first base should be adenine (A).
The complement mRNA strand should be: AUGGAACAUGGG 

[cnimm2000]

Hey guys,
I still dont seem to understand the benefits and the limitations of using quantitative and qualitative analysis. It would be great if someone can help.
thanks in advance .

[Kate Science]

Hey guys,
I still dont seem to understand the benefits and the limitations of using quantitative and qualitative analysis. It would be great if someone can help.
thanks in advance .

Hiya!
First off you've got to ask yourself, what do qualitative and quantitative mean?
Simply put, qualitative means what is there and quantitative means how much of it is there.

So from that we can suss out some quick pros and cons.
Qualitative observations can be done quickly and are easy to interpret (e.g. you can immediately see a precipitate form in a solubility test and thus conclude what's there, or e.g. you can see what colour flame a compound makes and thus easily say what metal is present (that's examples from HSC Chem Monitoring and Management)). The cons here though are that you cannot measure the amount of anything present - you can not get statistical, numerical results and your results could potentially be unreliable due the variable subjectivity of observation.

Quantitative research involves actually measuring the value of something. You can get a large sample size of data values that will give you a reliable statistical average but inaccuracies are more likely - is it 16.3 mm, 16.2 mm, or 16.42 mm long? (rather than the simpler qualitative option: is it longer than a 15cm ruler? yes or no.)

Both qualitative and quantitative research are valid approaches to experimental aims. Just remember:
Qualitative: yes or no?
Quantitative: how much?

[Razeen25]

Had my biology first hand practical on modelling polypeptide synthesis BUT I'M MAD. We had to make TWO models (one normal, one mutation) - we were only told we'd have to make one, and also answer short-answer questions + pedigree multiple choice AND WE WEREN'T EVEN TOLD UGHGHDSHFH.

I didn't finish (. There goes my good ranking from half-yearly.

Also the whole assessment was set up so bad, like my teacher realised DURING the assessment she forgot to print out charts for amino acids from mRNA codons and ugh so many other things were a complete mess smhh.
Depressed though, since it was worth 25% :/.

I guess what annoys me is that it's not my lack of understanding the content, but rather my not being able to cut and glue the pieces of paper in time. Like you'd think a HSC assessment would have a more efficient way of modelling a process than a kindergarten-style cut and paste activity, but anyways.

[BrittyG]

Had my biology first hand practical on modelling polypeptide synthesis BUT I'M MAD. We had to make TWO models (one normal, one mutation)

I didn't finish (. There goes my good ranking from half-yearly.

I guess what annoys me is that it's not my lack of understanding the content, but rather my not being able to cut and glue the pieces of paper in time. Like you'd think a HSC assessment would have a more efficient way of modelling a process than a kindergarten-style cut and paste activity, but anyways.

Wow, your practical assessment was so weird !! I had my prac a couple of weeks ago and we had to complete 3 practicals (Making a celery slide to identify Xylem and Phloem, estimate diameter of mammalian blood and recording effect of catalase in potato in hydrogen peroxide) and then answer questions on the other practicals in 9.2 and 9.4 (microbial growth, pH of carbon dioxide, microbes in decay). All up it was worth 80 marks and 25% as well.

The difference between our practical exams is massive. And the fact that yours was cut and paste is just really odd in my opinion, I agree, kindergarten stuff. As for thinking you've failed and your ranking going down, don't be disheartened. You still have your trials coming up (in which you most definitely won't have to cut and paste), work hard on your notes, do past HSC's, COME TO AN LECTURES  (<< Hopefully that linked to the lectures page it's my first time trying to link something) and work towards smashing your trial exam. It weighs the most (I think). Put this task behind you and keep working hard, you got this!!

P.S. your teacher seems a bit howz it goin 

[OverUnderachiever]

what's the difference between management, prevention, control and treatment of disease? they seem to all have different meanings?
if anyone could help, I'd be really grateful

[Kate Science]

what's the difference between management, prevention, control and treatment of disease? they seem to all have different meanings?
if anyone could help, I'd be really grateful

Here are some literature definitions and references if you’d like to do some extra reading:

Disease management is a system of coordinated heath care interventions and communications for defined patient populations with conditions where self-care efforts can be implemented. Disease management empowers individuals, working with other health care providers to manage their disease and prevent complications. (http://www.who.int/kobe_centre/ageing/ahp_vol5_glossary.pdf) *use this reference to look at different types/components of defining prevention too*

Disease control is a reduction in the incidence, prevalence, morbidity or mortality of an infectious disease to a locally acceptable level; elimination as reduction to zero of the incidence of disease or infection in a defined geographical area; and eradication as permanent reduction to zero of the worldwide incidence of infection. (http://www.who.int/bulletin/volumes/84/2/editorial10206html/en/)

Disease prevention is a procedure through which individuals, particularly those with risk factors for a disease, are treated in order to prevent a disease from occurring. Treatment normally begins either before signs and symptoms of the disease occur, or shortly thereafter. Treatment can include patient education, lifestyle modification, and drugs. (https://www.nature.com/subjects/disease-prevention) *don’t be confused by this use of treatment, it’s merely within the context of this definition, see below for the definition of disease treatment*

Disease treatment can simply be defined as a process designed to achieve a desired health status for a patient or client. (http://www.who.int/kobe_centre/ageing/ahp_vol5_glossary.pdf)


Okay now let’s make those more simple and succinct for the context of the HSC

Disease management: system implemented by health care bodies that focusses on what the individual can do themselves. 

Disease control: Deal with a present disease aiming to bring it down to ‘zero’ or ‘normal’ levels 

Disease prevention: how to stop the incidence of disease (avoid getting it in the first place) by using eduction, protection (vaccination, immunisation, physical barriers…), quarantine, ‘preventative treatment’, etc….

Disease treatment: How to fix the disease if you’ve got it? May be therapeutic treatment (drugs etc.), education and lifestyle changes (for non-communicable diseases like obesity), or any other method of bringing the patient back to health (NOTE: a treatment improves patient’s quality of life but does not necessarily cure the disease e.g. antiretroviral therapy for HIV doesn’t cure HIV but allows patients to lead relatively normal lives provided they stay on their medication). 

(am I right in thinking you’re looking at the tuberculosis dot point? I hope this is useful for that otherwise throw me a quick reply and I can help you out on that one specifically)

Cheers!

[kauac]

Hi...

For well-known substances like DNA and RNA, are we allowed to write their shorthand names in the exam?
Or do we actually have to write 'deoxyribose nucleic acid' etc?

[Opengangs]

Hi...

For well-known substances like DNA and RNA, are we allowed to write their shorthand names in the exam?
Or do we actually have to write 'deoxyribose nucleic acid' etc?

You can just write DNA and RNA; the syllabus even shortens it as well.

[kauac]

You can just write DNA and RNA; the syllabus even shortens it as well.

Sweet, that's a relief! Imagine how annoying the longer response questions would take if we had to write them out every single time! 

Thanks. 

[moq418]

How do you study for the hsc biology trials that are comming up soon?

[KT Nyunt]

How do you study for the hsc biology trials that are comming up soon?

I would suggest mainly consolidating your understanding of the 3 core topics so far (and maybe the option if you've done it). You could do this through:

Note making
During these holidays, if you haven't already it'd be a good idea to finalise your notes for all the topics: Maintaining a Balance, Blueprint of Life and A Search for Better Health. If you've already done this... then you could try condensing your notes or begin applying your knowledge...

Answering HSC Questions
A quick google search for "HSC Biology past papers" will get you pretty much all the material you need. You can find some from the NESA website here. Pay close attention to the marking guidelines and criteria as this will help you understand what exactly markers are looking for.

Practice extended response questions
A good place to try to maximise marks is in the extended response section. For this, you could try typing out responses, open book, and sending them to your teacher for feedback. Giving these a lot of thought and time will give you a good idea now, will help you form cohesive extended responses on the actual day. Also, these responses are supposed to test how well you can link and apply your knowledge, so by giving this a lot of time and effort, you're training yourself to think critically and will help you form these links between syllabus dot points.

Teaching
I've said this in many ATAR notes forums because it is honestly the most effective thing, I find, in my study routine. It REALLY helps to make content stick in an efficient and more engaging way. I would normally teach my parents or schoolmates, we'd get out a piece of paper or a whiteboard and I'd attempt to teach the content just as a classroom teacher would, drawing diagrams, writing key words etc. This also helps me measure how well I understand a topic as well as my ability to explain it. I would use my notes as prompters - if I rely on my notes heavily, I may need to revise this again later... or if I don't need it all all, and my explanations are clear (and correct), then I can move on to the next point. If you haven't tried adding this to your routine, I highly recommend you do. You'll surprise yourself on how much you actually understand, just by verbalising it.

I hope this was helpful! Good luck in your preparation for trials 

[itssona]

can anyone please explain how the dihybrid pea experiment is shown on punnet squares? :/ thank you

[Mate2425]

Hey guys, just wondering how often does the quarantine section of Search of Better Health, appear in the HSC?
Thank you.

[AngelWings]

can anyone please explain how the dihybrid pea experiment is shown on punnet squares? :/ thank you

I won't provide the answer, as you will not learn anything, but I'll explain that a dihybrid pea is heterozygous for two traits.
In the classic case performed by Mendel, the parents (P) are homozygous for the two traits (one is double homozygous dominant, the other is double homozygous recessive). Generally, the F2 are what is shown as the final answer.