VCE Biology Question Thread

[EllieMontgomery]

Apart from practice exams and questions, is there any other effective ways to prepare for the final end of year exam ? I know they run revision lectures and are they effective and worthwhile? Much thanks 

[Rameen]

Hi is this a sufficient answer to this question?


1.   Give a possible reason for why more copies of DNA may need to be produced?
When a DNA fragmented is extracted from the cell, it is too small to work with and analyse. Hence, PCR needs to occur to amplify that DNA fragment and produce multiple copies of it. This can make it easier to work with as for example, the band will become more visible in gel electrophoresis.

[darkz]

Hi is this a sufficient answer to this question?


1.   Give a possible reason for why more copies of DNA may need to be produced?
When a DNA fragmented is extracted from the cell, it is too small to work with and analyse. Hence, PCR needs to occur to amplify that DNA fragment and produce multiple copies of it. This can make it easier to work with as for example, the band will become more visible in gel electrophoresis.

This is a good answer, but you must make the distinction that the extracted DNA is of a small quantity i.e. not physically small.

[skollamkudy]

How much detail should be used when explaining PCR? Do we need to explain how the samples are prepared before they are placed in the thermal cycler? Also how do primers anneal to the DNA strands?

[darkz]

Hey guys,
I just got my sac back and one of the question was this (this was 2 marks):

"What causes mast cells to overreact and cause an allergic reaction?"

My answer was: Mast cells have igE antibodies embedded (teacher wrote that ige binds to mast cells rather than embed) on it's surface. Normally, an allergic reaction occurs when something small, like a pollen, binds to two or more igE antigen binding site, but people with allergies have mast cells with many igE, so there's a higher chance for pollen to cross-link more antibodies which causes mast cells to produce a chemical called histamines that binds to walls of capillaries to dilate blood vessels and increase permeability of vessels. (Lol I know I kinda overwrote it, but my teacher is highly pedantic so I wanted to make sure I covered every point.)

Maybe your teacher was after an answer which addressed why mast cells within specific people overreact. i.e. Why do we have people who have allergies, and those who don't. Hence, maybe they were looking for a description of the sensitisation process. Also, people with allergies do not have more IgE than those who don't - those who don't have allergies to a specific allergen don't have any for that allergen, and for allergies, when addressing the action of histamine, you should talk about how it can constrict airways and cause inflammation. (The action of histamine that you've provided is more for the immune response)

How much detail should be used when explaining PCR? Do we need to explain how the samples are prepared before they are placed in the thermal cycler? Also how do primers anneal to the DNA strands?

Don't think you'd need to talk about how the samples are prepared. Primers anneal to the DNA strands after the denaturation stage i.e. the double stranded DNA has become single-stranded, and therefore the complementary base-paired primers can anneal.

[J_Rho]

For Biology what is everyone's best method to study effectively? (flashcards, rote, mindmaps etc ??)

[caffinatedloz]

For Biology what is everyone's best method to study effectively? (flashcards, rote, mindmaps etc ??)

I write a lot of notes. Notes on the powerpoints, notes on Edrolo and notes on the textbook. On top of this I do practice questions from Edrolo, the textbook and BioBasics. Writing things out is how I get them in my head. Once they are in there, I practice applying them.

Also:
Does anyone know what the names are in sexually reproducing flowers? Our class looked at lilies in particular. I cannot for the life of me remember or find any information about them online. We did a prac about them but I didn't write down anything specific about the structures unfortunately. I would really appreciate any help or suggestions!

[Sine]

How much detail should be used when explaining PCR? Do we need to explain how the samples are prepared before they are placed in the thermal cycler? Also how do primers anneal to the DNA strands?

This has been a past VCAA question a few times. I would advise you to look up the answers that VCAA provide to be 100% exactly what you need to include in your answer to get full marks.

[thatdumbstudent]

Explain how an offspring may have a different genotype from either of their parents at a particular locus?

[colline]

Question for past bio students: which company exams would you recommend doing in the early stages of revision?

Our bio teacher gave all the students a stack of roughly 30 company exams today (mainly from TSSM, NEAP, and Lisachem) and I'm not quite sure where to start

I'm aware that company exams aren't as great in comparison to VCAA but do you think it's a bit early for VCAA exams right now?

Final question, how would TSSM, NEAP, and Lisachem compare to VCAA exams in terms of difficulty?

Thanks!!

[darkz]

Question for past bio students: which company exams would you recommend doing in the early stages of revision?

Our bio teacher gave all the students a stack of roughly 30 company exams today (mainly from TSSM, NEAP, and Lisachem) and I'm not quite sure where to start

I'm aware that company exams aren't as great in comparison to VCAA but do you think it's a bit early for VCAA exams right now?

Final question, how would TSSM, NEAP, and Lisachem compare to VCAA exams in terms of difficulty?

Thanks!!

These are my rankings in terms of exam quality:
1. NEAP (Around the same difficulty, though questions can be slightly more obscure)
2. Insight
3. TSSM
4. Lisachem (tbh, not that well made, wouldn't really recommend)
5. TSFX

So imo, you should start from the back -> front, leave the best till last. But only do that if you plan on actually completing them all

[colline]

These are my rankings in terms of exam quality:
1. NEAP (Around the same difficulty, though questions can be slightly more obscure)
2. Insight
3. TSSM
4. Lisachem (tbh, not that well made, wouldn't really recommend)
5. TSFX

So imo, you should start from the back -> front, leave the best till last. But only do that if you plan on actually completing them all

This is super helpful! Thank you so much!!

[J_Rho]

Do i have to print out the million past VCAA exams i want to do or can i get ones from my school or VCAA? (I really dont wanna print out 5 past exams for $55)

[Erutepa]

Do i have to print out the million past VCAA exams i want to do or can i get ones from my school or VCAA? (I really dont wanna print out 5 past exams for $55)

I usually just ask my teachers to print out the exams for me. Your science department at school will have a printing budget for printing out resources and what not, so i'm sure they'll be more than happy to print the exams for you.

[bi-and-ready-to-cry]

Why is pedigree analysis often the easiest way to investigate inheritance patterns in humans?

You can generally determine whether a trait is going to be dominant or recessive, sex-linked or autosomal pretty quickly. If your trait occurs in every generation then it is most likely dominant, if it occurs every now and then its probably recessive. If there is an equal amount of male:females then its autosomal, if more females are affected its X-linked dominant, if more males are affected its X linked recessive.

hope this helps!!