VCE Biology Question Thread

[Yacoubb]

Hi everyone!

It’s not often that I post on ATARNotes and I’d love to make a more regular contribution to the community – I hope to do so with this post! 

I completed Biology 3&4 this year and consulted this thread on a regular basis throughout the school year in preparation for each of my SACs and the end-of-year exam. To merely suggest that this thread has been ‘helpful’ is quite the understatement. I am in awe of the numerous members of the community (particularly Yacoubb, cosine, vox nihili, mtse, Elizawei, heidi, Sine, thushan, The Usual Student, Gogo14…agh, I could go on) who have so selflessly contributed to this thread and have assisted so many of us who have a genuine passion for and intend to do well in this subject.

I personally am not expecting a sensational result on December 12th; however I am certainly grateful for all of the assistance I have received simply by browsing the threads on a weekly basis. Although this post does not compare to the months of dedication and lengthy responses prepared by some truly wonderful members of this community, I hope it conveys my gratitude for all that you have done.

Thank you so very much.

Best of luck to all those who are yet to receive their results in the next month. I truly hope you receive the score you deserve – you’ve all worked so hard.

Not quite an interesting Biology fact, but certainly a series of truthful statements. 

I appreciate this a lot, thank you! It has certainly been my absolute pleasure helping to the best of my capacity. Best of luck for your results, and remember, don't like a study score dictate your passions and strengths.

Fun Biology Fact: the immune system of your gut (also known as mucosal immunity) has adapted itself so that even though you're constantly exposing the gut surface to the antigens of your commensals/normal flora and innocuous food antigens, you generate an immune response that is quite weak, through the production of IgA. These IgA antibodies, in the context of an important cytokine called TGF-beta, will help to down-regulate an immune response so that you don't constantly have an inflammatory response at your gut (which would be extremely painful and damaging).

[vox nihili]

Hey friends!


Not a question, strictly speaking (and as a mod I really should know better!) but I just wanted to drop by and wish you all the very best of luck tomorrow! As I've said a few times, I'm constantly impressed by how smart and brilliant you all are, so I have no doubt that tomorrow will bring you good news. On the off chance that it doesn't, please remember that your future in science has a lot more to do with the hard work and the curiosity you bring to the study of it, and not the scores you achieved in VCE.

GOOD LUCK

[Hydroxyl]

Hey friends!


Not a question, strictly speaking (and as a mod I really should know better!) but I just wanted to drop by and wish you all the very best of luck tomorrow! As I've said a few times, I'm constantly impressed by how smart and brilliant you all are, so I have no doubt that tomorrow will bring you good news. On the off chance that it doesn't, please remember that your future in science has a lot more to do with the hard work and the curiosity you bring to the study of it, and not the scores you achieved in VCE.

GOOD LUCK

This is an amazing post, we biologists love the support! Even though this is a week late, sorry guys XD!

[AR99]

Hey AN, what would you guys who have done bio recommend that i do for preparation for year 12. i didnt really do anything for year 11 bio and i need to really up my game for 3/4. Also for those who did it in year 12 and did well, do you have any tips for preparation and for the year. Thanks

[peanut]

Hey AN, what would you guys who have done bio recommend that i do for preparation for year 12. i didnt really do anything for year 11 bio and i need to really up my game for 3/4. Also for those who did it in year 12 and did well, do you have any tips for preparation and for the year. Thanks

I didn't do bio in year 12 (did it in year 11). Obviously, you could finish all your holiday homework but honestly, there's not much else to do. I don't think I prepared in the summer holidays before bio but you could start learning the course, but I wouldn't recommend this as you are likely to forget the content anyway (since the course is big, like really big). One thing I would recommend is getting REALLY familiar with the study design. Like I said, Biology is a really large course and it is easy to get carried away with learning things that are irrelevant to the course. Also. keeping on top of your work during the school year since there are 10? SACS. I know that sounds really cliché, but it is really important. Another thing is to reserve enough time to grind practice exams. I left about three months to grind practice exams (at this point, I had already finished the course before my school), but obviously this is differs for everybody.

[vox nihili]

Hey AN, what would you guys who have done bio recommend that i do for preparation for year 12. i didnt really do anything for year 11 bio and i need to really up my game for 3/4. Also for those who did it in year 12 and did well, do you have any tips for preparation and for the year. Thanks

Justhave a general read for interest, but don't push yourself. You deserve the rest before you start year 12 and there is plenty of time to learn the course during the year

[peanut]

Is it too early to be asking questions here :')?

I was wondering why the plasma membrane needs to be fluid - I haven't gotten the textbook yet and can't seem to find a definitive answer to this anywhere! My guess is to allow it to be semi-permeable?

Yep, that's one of the reasons! In other words, it allows the cell to regulate its inputs and outputs.

[vox nihili]

Is it too early to be asking questions here :')?

I was wondering why the plasma membrane needs to be fluid - I haven't gotten the textbook yet and can't seem to find a definitive answer to this anywhere! My guess is to allow it to be semi-permeable?

The fluidity kind of helps with the permeability, I guess, but you could still have this with a solid membrane.

There are a number of reasons why a fluid membrane is useful. It makes the cell better able to withstand mechanical forces, as the fluidity allows the cell membrane to be distorted without breaking. It also allows stuff to move throughout the membrane and distribute itself (e.g. proteins that are embedded in the membrane can spread around a bit). There are other reasons we could go into, but they're a bit beyond what you'd need to think about in VCE.

Really interesting question though

[vcestressed]

How do prokaryotic cell walls differ from plant cell walls?

I know plants have cellulose so a carbohydrate molecule but isnt that similar to what prokaryotic cell walls have too?

[vox nihili]

How do prokaryotic cell walls differ from plant cell walls?

I know plants have cellulose so a carbohydrate molecule but isnt that similar to what prokaryotic cell walls have too?

You don't really need to know the details, but prokaryote cell walls are made of a substance called lipopolysaccharide as opposed to cellulose of the plant cell wall

[vcestressed]

Thank you!

[strawberry7898]

Why is the surface area to volume ratio important in cells? I understand it's to do with chemical activity being greater in larger cells, why does a large cell have more difficulty transporting enough materials?

[Sine]

Why is the surface area to volume ratio important in cells? I understand it's to do with chemical activity being greater in larger cells, why does a large cell have more difficulty transporting enough materials?

So SA:V  gets larger as the cell becomes smaller. Transport across the plasma membrame is required for the cell to function. If the cell has a small surface area(large Volume hence small Sa:V) these processes won't be fast enough to sustain the cells life.

I see your doing biomed @ monash, are you revising vce stuff or is this uni stuff? 

[vcestressed]

Hey, I was doing chem a few days ago and i read that hydrogen bonds are the strongest types of bonds but in bio, i read that hydrogen bonds are pretty weak and easy to break (so i read about the protein's 3D structure that is held together by weak hydrogen bonds). What am i missing? I am really confused.

[Sine]

Hey, I was doing chem a few days ago and i read that hydrogen bonds are the strongest types of bonds but in bio, i read that hydrogen bonds are pretty weak and easy to break (so i read about the protein's 3D structure that is held together by weak hydrogen bonds). What am i missing? I am really confused.

hydrogen bonds are relatively weak . They are just stronger dipole-dipole interactions. Covalent bonds are the strongest bond.

Proteins 3D structure (tertiary structure) is held together by Hydrogen bonds,covalent bonds, ionic bonds(disulfide bridges) & dispersion forces this all depends on the different Z groups on the amino acids (also called R groups)