VCE Biology Question Thread

[Chocolatepistachio]

Why can sugars be stained by silver nitrate and why does sucrose stain lighter

[caffinatedloz]

Why can sugars be stained by silver nitrate and why does sucrose stain lighter

When silver nitrate reacts with a reducing sugar it undergoes a process called reduction and solid silver is formed. Have a look at the image attached below demonstrating what the stain looks like. The reason that sucrose stains far lighter is that it is not a reducing sugar. That means it does not allow silver nitrate to undergo reduction and no solid silver (which gives the dark black colour) is formed. I'm not sure if you need to know all of the redox chemistry; the question probably just wants you to know that sucrose (unlike glucose) is not a reducing sugar.

[Chocolatepistachio]

Can someone explain why non reducing sugars do not form an osazone structure

[Billuminati]

Can someone explain why non reducing sugars do not form an osazone structure

The hydrazine must attack an electrophilic C=O group and non-reducing sugars don’t have one available since ring opening is difficult as I’ve explained to you the other day

[Chocolatepistachio]

A mother cell has completed meiosis I. Which of the following best describes the two daughter cells?
A they have half the number of chromosomes but the same amount of DNA as the mother cell
B they have half the amount of DNA as the mother cell
C they have an identical number of chromosomes and amount of DNA as the mother cell
D they have half the number of chromosomes but twice the amount of DNA as the mother cell

Would this be a

[Jimmonash1991]

G'day,

I have a young bloke who i am taking for 3 & 4 biology tutoring. My background is Biomedical Science at Monash (no braggardacio, promise), and my usual game is VCE maths, chemistry and physics.

My question is: how can I get the best start and best communicate 3/4 biology?

I have no issues with the content but I don't want to be pumping out pages of notes. My thinking is doing plenty of past exam questions and checkpoints? I believe there are exam preparation resources out there too, as I have them for all the maths.

I am confident I can help this fella, but would love some insight from those who have taught biology themselves.

[lastapasta]

A mother cell has completed meiosis I. Which of the following best describes the two daughter cells?
A they have half the number of chromosomes but the same amount of DNA as the mother cell
B they have half the amount of DNA as the mother cell
C they have an identical number of chromosomes and amount of DNA as the mother cell
D they have half the number of chromosomes but twice the amount of DNA as the mother cell

Would this be a

yep that's correct!

[Harrycc3000]

G'day,

I have a young bloke who i am taking for 3 & 4 biology tutoring. My background is Biomedical Science at Monash (no braggardacio, promise), and my usual game is VCE maths, chemistry and physics.

My question is: how can I get the best start and best communicate 3/4 biology?

I have no issues with the content but I don't want to be pumping out pages of notes. My thinking is doing plenty of past exam questions and checkpoints? I believe there are exam preparation resources out there too, as I have them for all the maths.

I am confident I can help this fella, but would love some insight from those who have taught biology themselves.

Hey Jim,
I'm not a biology tutor but I had a biology tutor who I thought was extremely capable and good at what they did. Most lessons just included talking through the content, but lots of I guess 'model answers' and 'mnemonics' to answer the standard questions correctly as well as to remember content like for examples the types of cells involved in the innate immune system. No notes were provided but I thought just writing my own notes while they talked was sufficient. Once I got to some level of competency in the content we were learning then they would go through some past exam questions in the tutoring sessions, and I thought it was good to immediately apply what I had just learnt in a practice question. I think that the most valuable thing I had from them as a tutor was the amount of questions that they were willing to ask, both during class and online I could ask any question and they would answer in extreme detail to clarify a lot of things. In summary, I think that notes aren't necessary, concrete definitions and model answers help, going through practice questions is the correct go and just being there to answer questions for your student in bio is the most valuable thing (at least in my opinion). Hope this helps!

Also, there are many of the same company papers as there in maths including neap, insight, stav (instead of mav) etc. if you can find them.

[Chocolatepistachio]

If someone could help with this question 

[Pigeon123]

What is the etymology for archea? Is there a trusted etymology dictionary I can use because I get mixed up with the other meanings?

[nezukosbamboopipe_0]

If I take VCE Biology units 1&2 in year 10, does that mean I have to repeat it in year 11? Also, does my scores from year biology affect my atar?

[Bri MT]

If I take VCE Biology units 1&2 in year 10, does that mean I have to repeat it in year 11? Also, does my scores from year biology affect my atar?

No.
I took bio 12 in year 10 then did 34 in year 11 - this is the normal pattern for people who do 12 in year 10.

Only scores from units 3&4 affect your ATAR.

[nezukosbamboopipe_0]

No.
I took bio 12 in year 10 then did 34 in year 11 - this is the normal pattern for people who do 12 in year 10.

Only scores from units 3&4 affect your ATAR.

Thanks!

[AngelWings]

What is the etymology for archea? Is there a trusted etymology dictionary I can use because I get mixed up with the other meanings?

According to a quick Google search, the etymology of archaea is “ancient” or “primitive” from Greek “arkhaios”. Not sure about trusted etymological dictionaries though.

Does anyone know for this question i got 100000

My answer

If I’m correct (been a few years since I’ve done this), I got B.

my explanation

It’s an application of c₁v₁=c₂v₂.

Spoiler

c₁= 15uM v₁=5ml = 5000ul
c₂=300uM

Substitute and rearrange correctly.  That gives 250ul.

Only thing you need to be wary of is that they said 5ml, which you’d need to convert to ul as all the MCQ answers are in ul.

@others checking: Please let me know if I’m wrong or right. Will gladly learn from this.

If someone could help with this question 

Where are you stuck with this question? And what answer did you get?

[demibour]

hey! im doing biol 3/4 this year does anyone have any good mnemonics ?