VCE Biology Question Thread

[amber13lol]

Hi everyone,
I failed my photosynthesis SAC, and I'm pretty disappointed. I saw it coming as I just skimmed my way through unit 1/2. Any tips to improve? Thanks

[vox nihili]

Hi everyone,
I failed my photosynthesis SAC, and I'm pretty disappointed. I saw it coming as I just skimmed my way through unit 1/2. Any tips to improve? Thanks

I'm really sorry to hear that Glad you're here to try to improve rather than getting down on yourself as so many do! What do you think you need to change for next time? Personally, I've always found that students who do well tend to be those who can be self-reflective about their performance.

Alright so I have a question.
In my SAC, one of the questions asked us to explain how the reaction between gelatin and bromelain is a condensation reaction or something along those lines. In the heat of the moment, I just tried to vaguely justify why it is and I got full marks, but wouldn't it be a hydrolysis reaction? As the gelatin is being broken down into amino acids?
My teacher says that hydrolysis is just a type of condensation reaction but I can't find anything online that says that? Is that true?

Hydrolysis literally means water (hydro) breaking (lysis). It refers to reactions wherein water is used to break open a bond. Condensation, on the other hand, refers to reactions wherein water is an output (not an input as in hydrolysis).

tl;dr your teacher is seriously wrong. They're not the same; they're the opposite.

[ssillyssnakes]

Hydrolysis literally means water (hydro) breaking (lysis). It refers to reactions wherein water is used to break open a bond. Condensation, on the other hand, refers to reactions wherein water is an output (not an input as in hydrolysis).

tl;dr your teacher is seriously wrong. They're not the same; they're the opposite.

That's what I thought... Idk whether to raise it to her again though because I don't want to lose marks lol

[vox nihili]

That's what I thought... Idk whether to raise it to her again though because I don't want to lose marks lol

Just google hydrolysis vs condensation or look it up in your textbook. It's incontrovertible as you've described it.

[Rameen]

Hi

I am confused as to whether the active site of an enzyme binds to the substrate or is it vice versa?
I know that the active site of an enzyme and a substrate collide, however, I am unsure which binds.

It would be appreciated if you could help me.

Thanks!

[vox nihili]

Hi

I am confused as to whether the active site of an enzyme binds to the substrate or is it vice versa?
I know that the active site of an enzyme and a substrate collide, however, I am unsure which binds.

It would be appreciated if you could help me.

Thanks!

Do you hug your friend or does your friend hug you? Answer is you both hug each other. Same with enzymes and substrates.

[maheenkhan]

I have a SAC coming up for bio 3/4 on photosynthesis and cellular respiration that is composed of an experiment and discussion questions based on it. My teacher said to study enzymes, photosynthesis and cellular respiration. I was wondering if anyone has any ideas about what the prac might be and any tips in general. Thanks!

[PhoenixxFire]

I have a SAC coming up for bio 3/4 on photosynthesis and cellular respiration that is composed of an experiment and discussion questions based on it. My teacher said to study enzymes, photosynthesis and cellular respiration. I was wondering if anyone has any ideas about what the prac might be and any tips in general. Thanks!

Hey!
Welcome to AN

Are you going to be doing the experiment and discussion questions on different days or together? If they're done separately then I'd imagine that you'll probably be told what the prac is.

A couple of common ones that I can think of are the catalase experiment (probably run somewhat like this) or testing photosynthesis by timing how long leaf discs take to float in different setups (which can be used to test a few different parts of photosynthesis).

The discussion questions will probably be a mix of experimental design (e.g. write a hypothesis) and theory questions (e.g. explain why some discs took longer to float). The most important thing to remember is to make your answers specific to the experiment you are writing about, don't just write out memorised responses.

[SmartWorker]

Hi there,

I am currently doing Bio 1/2, I was wondering how to take notes. During Term 1 I used to exhaustedly take notes on every minute thing in the textbook (Jacaranda by the way) and in the end would not have time to do practice questions and would not remember anything I had spent hours studying on.

Thank You.

[Erutepa]

I have a SAC coming up for bio 3/4 on photosynthesis and cellular respiration that is composed of an experiment and discussion questions based on it. My teacher said to study enzymes, photosynthesis and cellular respiration. I was wondering if anyone has any ideas about what the prac might be and any tips in general. Thanks!

Usually the experiment will be set up to determine the effect of a variable such as temperature or light or gas concentration (wither oxygen or carbon dioxide) on the rates of photosynthesis/cellular respiration. I personally did a prac whereby we put crickets in a sealed test tube which contained potassium hydroxide. The potassium hydroxide would react with the CO2 to form non-gaseous compounds such that as cellular respiration occured and CO2 was produced by the crickets, this reaction would reduce the pressure in the test tube. By measuring this pressure change over-time we were able to obtain indication of the rate of cellular respiration and had to thus suggest why it decreased over the duration of the experiment (this was because the oxygen gas concentration decreased and acted as a limiting factor of cellular respiration, thus slowing the production of CO2 and the resultant reduction in air-pressure).

There are many different ways you could set up an experiment to experimentally identify the impact of a variable on the rates of cellular respiration/photosynthesis, so what I would make sure I know and studied for is the different factors influencing the rates of these processes (as well as understanding the processes mechanistically). Apart from that, it's important that you understand experimental design and how to approach analysing results. For these kind of thinking skills, there is a great thread here

Hi there,

I am currently doing Bio 1/2, I was wondering how to take notes. During Term 1 I used to exhaustedly take notes on every minute thing in the textbook (Jacaranda by the way) and in the end would not have time to do practice questions and would not remember anything I had spent hours studying on.

Thank You.

I took fairly detailed notes myself as I did 3/4 biology, but was able to make them fairly quickly since I was not slowed too much down my trying to make them look pretty. While It is important to set you notes out so that they are readable and easy to study, I know a few people who spend ages of making very very pretty looking notes and wasting a lot of time. If this is something you are doing, maybe try to find a better balance and speed up your note taking.
Another thing is that while I did take detailed notes, I did not write stuff that I already knew. For example, I covered the dynamics of the plasma membrane in fair depth during unit 1, so I didn't waste time making more notes in unit 3, and just went straight into questions.

Regarding not being able to remember specific details, what I found worked well for me was studying consistently through different forms. After making notes and reading through them, I would try to draw I flowchart/diagram, I would watch videos on the topics, and listen to podcasts (like douchy's) on topics. This way you are getting multiple exposures to information as well as getting that information in different forms from different sources.

[PhoenixxFire]

Hi there,

I am currently doing Bio 1/2, I was wondering how to take notes. During Term 1 I used to exhaustedly take notes on every minute thing in the textbook (Jacaranda by the way) and in the end would not have time to do practice questions and would not remember anything I had spent hours studying on.

Thank You.

Hey!

There's a lot of different ways to take notes, there's not really a right way - just a way that's right for you.

If you find you're running out of time then that probably means your current way isn't working. I'd suggest trying a few different ways to take notes over the rest of this year and figuring out what works best for you so you're prepared for next year.

Personally I don't write that many notes - I don't see any point. If you're going to write notes on everything in the textbook then you may as well just read the textbook instead. I only take notes on things that I don't already know. For example if your teacher says that glucose is the product of photosynthesis, and you already know that well enough to be sure you won't forget it, then there's no point writing it down.

I also found that it was easier to draw annotated diagrams rather than write paragraphs. Even if it wasn't something that really needed a drawing, I would use arrows to show links between concepts rather than describing how they're related.

Something you could try if you're struggling to figure out how to write less is to go back through your old notes and cross out everything that isn't important and that you didn't need to write down (alternatively, highlight the stuff that you actually did need to write down if you don't want to make your notes too messy). Sometimes it's easier to look over old notes and figure out how much you should have written rather than trying to figure it out as you write notes for the first time, and it should help give you an idea of what to include in your notes from now on.

[Evolio]

Hi guys.
How are you doing?
I just had a question. You know how signalling molecules bind to specific receptors? Can we say that the receptor site has a complementary shape to that of the signalling molecule?
For example:
This question is from edrolo.
'A hormone was produced in one cell, entered the bloodstream and travelled to two groups of cells adjacent to each other. One group of cells responded to the hormone but the neighbouring group did not.
What is the most likely reason for this difference in response by cells to the same hormone?
My response:
This is because one of the cells had a complementary-shaped receptor site to the signalling molecule so it responded to the hormone while the other cell did not so it did not respond to the hormone.
This question was one mark. I was just wondering if my answer would be marked correct?

[Erutepa]

Hi guys.
How are you doing?
I just had a question. You know how signalling molecules bind to specific receptors? Can we say that the receptor site has a complementary shape to that of the signalling molecule?
For example:
This question is from edrolo.
'A hormone was produced in one cell, entered the bloodstream and travelled to two groups of cells adjacent to each other. One group of cells responded to the hormone but the neighbouring group did not.
What is the most likely reason for this difference in response by cells to the same hormone?
My response:
This is because one of the cells had a complementary-shaped receptor site to the signalling molecule so it responded to the hormone while the other cell did not so it did not respond to the hormone.
This question was one mark. I was just wondering if my answer would be marked correct?

Yes, I think this would be right, I would just probably want to specify that the other cells did not respond BECAUSE they did not possess this complementary receptor and thus did not interact with the signaling molecule

[Evolio]

Cool!
Thank you, Erutepa!
 

[maheenkhan]

Hey!
Welcome to AN

Are you going to be doing the experiment and discussion questions on different days or together? If they're done separately then I'd imagine that you'll probably be told what the prac is.

A couple of common ones that I can think of are the catalase experiment (probably run somewhat like this) or testing photosynthesis by timing how long leaf discs take to float in different setups (which can be used to test a few different parts of photosynthesis).

The discussion questions will probably be a mix of experimental design (e.g. write a hypothesis) and theory questions (e.g. explain why some discs took longer to float). The most important thing to remember is to make your answers specific to the experiment you are writing about, don't just write out memorised responses.

Thank you so much!
We will be doing the discussion questions straight after the prac.