Biology External Exam

[s110820]

Hey everyone,

The Biology External Exam is fast approaching (someone please do the maths me as to when the exam actually is). How are you guys feeling about this exam? What was your favourite topic in Unit 3? What was your favourite topic in Unit 4? Did you enjoy studying Biology, if so, why? Sorry if it's a lot of questions, I just wanted to start a conversation on this board and hopefully, keep this conversation rolling as the big day draws nearer.

Keep studying and look after yourself,

Darcy Dillon.

P.S. I was also thinking of creating more specific topics on this board such as a topic for each individual topic in the exam, study preparation and what we can do to mentally prepare ourselves for the big day. If you guys have any other ideas, feel free to add more topics to this board as I'm sure the entire QCE community would really appreciate it

[babo]

I was wondering if we are meant to know about point and frameshift mutations as on the syllabus it says we dont need to know their effect?   

[s110820]

I was wondering if we are meant to know about point and frameshift mutations as on the syllabus it says we dont need to know their effect?   

Hey Babo,

I would study the point and frameshift mutations (& their effects) just in case. A few questions based on frameshift and point mutations popped up on a few of my mock exams, so I think that it would be better to be safe than sorry. Also, have you heard about how to answer the "compare" types of questions? There's a specific trick to it that not many schools know about because it's not specified in the syllabus either.

Hopefully, that helps

Have a great week and kind regards,

Darcy Dillon.

[Bri MT]

I was wondering if we are meant to know about point and frameshift mutations as on the syllabus it says we dont need to know their effect?   

Hey,

welcome to the forums!

you should know about them, just not about their effects in terms of how those mutations impact translation. I.e. you should know what point and frameshift mutations are but you don't need to know about the missense, nonsense, or silent impacts

I hope this helps

[babo]

Alright thankyou! and for pedigrees, they have not been mentioned by the syllabus, yet they came in the mocks..

[s110820]

Hey,

welcome to the forums!

you should know about them, just not about their effects in terms of how those mutations impact translation. I.e. you should know what point and frameshift mutations are but you don't need to know about the missense, nonsense, or silent impacts

I hope this helps

Hey Bri,

I have to disagree with you a little bit on what you said about the mutations - we do actually need to know the difference betweens missense, nonense and silent mutations as well as their specific impacts on biological processes. I definitely had a few questions on my mock exams about these types of mutations so again, I think it's better to be safe than sorry.

Hopefully, that helps

Have a great week and kind regards,

Darcy Dillon.

[babo]

Alright thankyou! and for pedigrees, they have not been mentioned by the syllabus, yet they came in the mocks..

[Bri MT]

Hey Bri,

I have to disagree with you a little bit on what you said about the mutations - we do actually need to know the difference betweens missense, nonense and silent mutations as well as their specific impacts on biological processes. I definitely had a few questions on my mock exams about these types of mutations so again, I think it's better to be safe than sorry.

Hopefully, that helps

Have a great week and kind regards,

Darcy Dillon.

Hey Darcy,

I would always rather be challenged if that means that people can get more accurate info or things can be clarified so thank you.

The reason I have said missense, nonsense etc. does not need to be known is because in the syllabus this is explicitly stated.

Page 56: https://www.qcaa.qld.edu.au/downloads/senior-qce/syllabuses/snr_biology_19_syll.pdf

" Students are not required to identify the effects of mutations (i.e. silent, missense, nonsense)"

At least in other states, I have noticed in the past issues with mock exams where the syllabus has not been fully followed and questions are not completely indicative of what would actually appear on an exam. The most trusted source of information should always be QCAA and especially current QCAA documents such as the syllabus, then other material which may have been produced in support of this.

Ultimately, the difference between missense, nonsense and silent is not hard to learn so if anyone would feel more comfortable in learning these I'm not going to say you can't; however, the syllabus provides clear instruction about this being unnecessary.

I hope you have a great week too


Edit:

Alright thankyou! and for pedigrees, they have not been mentioned by the syllabus, yet they came in the mocks..

From the syllabus:

"predict frequencies of genotypes and phenotypes using data from probability models (including frequency histograms and Punnett squares) and by taking into consideration patterns of inheritance for the following types of alleles: autosomal dominant, sex linked and multiple"
(page 56)

imo it is not unreasonable for patterns of inheritance to be shown in a pedigree and for you to be expected to interpret those.

[babo]

Thanks bri 

[s110820]

Hey Darcy,

I would always rather be challenged if that means that people can get more accurate info or things can be clarified so thank you.

The reason I have said missense, nonsense etc. does not need to be known is because in the syllabus this is explicitly stated.

Page 56: https://www.qcaa.qld.edu.au/downloads/senior-qce/syllabuses/snr_biology_19_syll.pdf

" Students are not required to identify the effects of mutations (i.e. silent, missense, nonsense)"

At least in other states, I have noticed in the past issues with mock exams where the syllabus has not been fully followed and questions are not completely indicative of what would actually appear on an exam. The most trusted source of information should always be QCAA and especially current QCAA documents such as the syllabus, then other material which may have been produced in support of this.

Ultimately, the difference between missense, nonsense and silent is not hard to learn so if anyone would feel more comfortable in learning these I'm not going to say you can't; however, the syllabus provides clear instruction about this being unnecessary.

I hope you have a great week too


Edit:
From the syllabus:

"predict frequencies of genotypes and phenotypes using data from probability models (including frequency histograms and Punnett squares) and by taking into consideration patterns of inheritance for the following types of alleles: autosomal dominant, sex linked and multiple"
(page 56)

imo it is not unreasonable for patterns of inheritance to be shown in a pedigree and for you to be expected to interpret those.

Hey Bri,

Thank you so much for your lovely and thoughtful response! I really appreciated understanding your perspective. However, the mock exams I mentioned in my previous response also included the QCAA mock exams, which is why I advised @babo to study these types of mutations and their effects just in case.

Hopefully, that helps to clarify your thoughts

Have a great week and kind regards,

Darcy Dillon.

[Bri MT]

Hey Bri,

Thank you so much for your lovely and thoughtful response! I really appreciated understanding your perspective. However, the mock exams I mentioned in my previous response also included the QCAA mock exams, which is why I advised @babo to study these types of mutations and their effects just in case.

Hopefully, that helps to clarify your thoughts

Have a great week and kind regards,

Darcy Dillon.

Hey Darcy,

No worries at all!

I wonder whether the mocks were made before the syllabus was finalised or something. In any event,  while I trust the syllabus as the most important document guiding what's assessable I completely understand why you'd be cautious given the mocks - especially Queensland being new to externals as well - and ultimately if learning this small topic helps you feel more comfortable I can certainly understand why you would do that and advise others accordinly. I'm glad we've had this convo rather than staying silent so that people can make an informed decision when it comes to their study

Best of luck to you too!

[XD12345]

Hi Forum,

I’ve been trying to revise the law of independent assortment and the law of segregation that Mendel proposed after finishing the inheritance experiments.

I’ve read through the definitions and I understand what they state but I’m not sure how to apply it to the context. So my question is:

What does the law of segregation and the law of independent assortment actually mean?

And how do these laws fit into inheritance?

And how do these laws assist genetic variation?

Thank you!

[Bri MT]

Hi Forum,

I’ve been trying to revise the law of independent assortment and the law of segregation that Mendel proposed after finishing the inheritance experiments.

I’ve read through the definitions and I understand what they state but I’m not sure how to apply it to the context. So my question is:

What does the law of segregation and the law of independent assortment actually mean?

And how do these laws fit into inheritance?

And how do these laws assist genetic variation?

Thank you!

Hi!

So the point of it is this: each diploid organism (e.g. us) has 2 copies of each gene.

The law of segregation is about how when someone makes a gamete, that gamete gets contains one of the two copies, and so the offspring formed by one gamete from each parent then has one copy of each gene from each parent. This means that the offspring isn't a genetically identical copy to either of its parents nor just an "average" of their traits (can you see how this fits into genetic variation?).

The law of independent assortment tells us that the probability of inheriting one allele doesn't change based on what other alleles we've inherited (note that this is not true for genes on the same chromosome!). Without this, you'd expect much less diversity in what combinations of alleles the offspring has. Independent assortment is actually really important for making it so that we can remove deleterious (bad) alleles from the population without making the whole lineage go extinct, and that's thought to be one major reason why so many species have sexual reproduction. This might be a little confusing, lmk if you want a diagram or something to clear this up more

I hope this helps!

[XD12345]

Hi!

So the point of it is this: each diploid organism (e.g. us) has 2 copies of each gene.

The law of segregation is about how when someone makes a gamete, that gamete gets contains one of the two copies, and so the offspring formed by one gamete from each parent then has one copy of each gene from each parent. This means that the offspring isn't a genetically identical copy to either of its parents nor just an "average" of their traits (can you see how this fits into genetic variation?).

The law of independent assortment tells us that the probability of inheriting one allele doesn't change based on what other alleles we've inherited (note that this is not true for genes on the same chromosome!). Without this, you'd expect much less diversity in what combinations of alleles the offspring has. Independent assortment is actually really important for making it so that we can remove deleterious (bad) alleles from the population without making the whole lineage go extinct, and that's thought to be one major reason why so many species have sexual reproduction. This might be a little confusing, lmk if you want a diagram or something to clear this up more

I hope this helps!

Thank you, this helped me a lot. The textbook has a very plain definition, so this really cleared it up.

[XD12345]

Hey everyone,

So bio is done and I really need an answer for the last question on paper 2. I am really nervous because it was worth a lot and I am reallllllyyyy sure they did not give enough information.

The question stated that the 3 time points were leading up to the speciation now, if the speciation occurred like the gene flow was in the most recent time point, it would have been parapatric speciation right? Because the population wasn’t isolated (there was still gene flow between two sub populations).

But in theory, if the speciation occurred later, the gene flow could have been fully reduced because that was the trend, making the population isolated, and the answer being allopatric speciation!

The question says the data is “leading up to the speciation event” but without knowing when the population developed reproductive isolation mechanisms, it could either be parapatric or allopatric (not sympatric because gene flow stopped between the target population and populations B and C)

Anyway,
What did you all think of that question? Am I being crazy or was there actually some critical information missing?