VCE Biology Question Thread

[doomdestroyer]

Can someone please help me with this question? It's from the sample exam from VCAA but the answers have not been provided.

Thanks!

I believe this question was already answered on this thread, something about the receptors breaking off after a certain amount of stimulation? Just look back on this thread and find the discussion on this question, i don't really understand it either.

[grannysmith]

what is the difference between pathogens and antigens?

Pathogens are disease causing organisms or acellular agents, whereas antigens are molecules which elicit an immune response (ANTIbody GENerating).
Pathogens have antigens because they are not 'self', and so any of the (protein) molecules on their surfaces are antigens.

[grannysmith]

Can someone please help me with this question? It's from the sample exam from VCAA but the answers have not been provided.

Thanks!

Yeah, this q has been answered.
Basically, receptor sites degrade over time and so become less effective in binding with the hormone; or receptors are taken in by a cell of they are stimulated too much, and so less receptors means a reduced response.

[chekside]

The answer supports C?

The explanation they provide says that after the 2 cycles there will be 2 hybrid strands and 2 fully unlabelled strands. Option C has 2 hybrid strands and 2 fully labelled strands whereas option D has 2 hybrid strands and 2 fully unlabelled strands, so the explanation they provide indicates that it is D however they say the answer is C.

[doomdestroyer]

The explanation they provide says that after the 2 cycles there will be 2 hybrid strands and 2 fully unlabelled strands. Option C has 2 hybrid strands and 2 fully labelled strands whereas option D has 2 hybrid strands and 2 fully unlabelled strands, so the explanation they provide indicates that it is D however they say the answer is C.

Try reporting the error so it can be amended.

[Tyleralp1]

The explanation they provide says that after the 2 cycles there will be 2 hybrid strands and 2 fully unlabelled strands. Option C has 2 hybrid strands and 2 fully labelled strands whereas option D has 2 hybrid strands and 2 fully unlabelled strands, so the explanation they provide indicates that it is D however they say the answer is C.

Isn't this question a mix of normal DNA mixed with labelled strands?
So the first replication will consist of the two stands, each being one normal and labelled strand (hybrid)
On the second cycle, these two strands will split, and complementary labelled strands join. This would create 2 hybrid, and 2 fully labelled?

[chekside]

Isn't this question a mix of normal DNA mixed with labelled strands?
So the first replication will consist of the two stands, each being one normal and labelled strand (hybrid)
On the second cycle, these two strands will split, and complementary labelled strands join. This would create 2 hybrid, and 2 fully labelled?

Sorry, yea you're right.
For some reason I read it the wrong way around and though it was radioactively labelled DNA molecule and unlabelled nucleotides 

[flares]

How is Australopithecus related to the homo species?

[Zailiner]

Is the knowledge of guard cells and leaves in general required? For example the movement of potassium ions within the guard cell or
knowing why the wilting of leaves affects the rate of photosynthesis.

I'm working on the decade old past exams and these are coming up quite frequently.

What are the specific things I should ignore in the older exams?

Cheers!

[infecthead]

Do we need to know each plant hormone and what they do? My Bio teacher said we don't, and if VCAA puts a question up regarding them they will give enough information in the stem but I just wanna make sure.

[Tyleralp1]

Is the knowledge of guard cells and leaves in general required? For example the movement of potassium ions within the guard cell or
knowing why the wilting of leaves affects the rate of photosynthesis.

I'm working on the decade old past exams and these are coming up quite frequently.

What are the specific things I should ignore in the older exams?

Cheers!

No

Do we need to know each plant hormone and what they do? My Bio teacher said we don't, and if VCAA puts a question up regarding them they will give enough information in the stem but I just wanna make sure.

No

[infecthead]

No

No

thank fuck

[katiesaliba]

How is Australopithecus related to the homo species?

Yep!

[Damo23]

Few MC Q's I don't quite get

For first question(Q5) got no clue, second one(Q11)why can't the answer be A, third one(17) why can't it be C, fourth one(21)I get how but by elimination but what do they mean by saturates and lastly question and lastly why can't Q23(bout the spraying levels decline stuff)from the 2010 unit 4 exam be also be D.

[katiesaliba]

Are my descriptions for the functions of these two organelles okay:

-Golgi apparatus modifies and packages materials into vesicles for secretion by the cell.
-Endoplasmic reticulum transports materials within the cell.

Also, when antigens are engulfed via endocytosis they form vesicles right? Because I swear some assessment reports have said vacuoles rather than vesicles?