VCE Biology Question Thread

[vox nihili]

Thanks, sorry didn't know it was answered

Don't worry! I'd be pretty impressed if you'd remembered

[Reus]

Does anyone happen to  know where to find the solutions for the sample exam? It only has multiple choice:/

They're just questions from past exams so you'll come across them

[Reus]

What does it mean by "the cell is ‘shocked’ to stimulate cell division, it is then implanted." when describing the process of genetic cloning? Thanks

[RazzMeTazz]

For Question 20 (attached below) the correct answer is A but I answered D.

Why can this method of dating not be used to date the fossil but it can be for the volcanic layer? Would it be to do with knowing that volcanic  rock is more likely to contain these minerals than the fossil?

And for Question 24. I answered B but the answer is A.
Could someone please explain why A is incorrect, because I thought as hominins evolved into the genus Homo, the brow ridge became less prominent?

Thankyou!

[shivaji]

For Question 20 (attached below) the correct answer is A but I answered D.



Why can this method of dating not be used to date the fossil but it can be for the volcanic layer? Would it be to do with knowing that volcanic  rock is more likely to contain these minerals than the fossil?

And for Question 24. I answered B but the answer is A.
Could someone please explain why A is incorrect, because I thought as hominins evolved into the genus Homo, the brow ridge became less prominent?

Thankyou!

For the question 20: potassium-argon is used to date inorganic matter, not organic matter. (not found in animals) hence, it dates the rock in which the fossil is found in, not the fossil itself. only carbon dating is used to date the fossil itself as that dates organic matter. (which is also why it decays more quickly)

For question 24: It's not A because thumbs don't grow on our feet, and hominins have parallel digits (that's why hominins are bipdeal). Also, you are tight the trend is that the brow ridge reduces over hominin evolution. However, relative to apes and alike, the early hominins would have had a less prominent brow ridge, so B is correct.

[RazzMeTazz]

For the question 20: potassium-argon is used to date inorganic matter, not organic matter. (not found in animals) hence, it dates the rock in which the fossil is found in, not the fossil itself. only carbon dating is used to date the fossil itself as that dates organic matter. (which is also why it decays more quickly)

For question 24: It's not A because thumbs don't grow on our feet, and hominins have parallel digits (that's why hominins are bipdeal). Also, you are tight the trend is that the brow ridge reduces over hominin evolution. However, relative to apes and alike, the early hominins would have had a less prominent brow ridge, so B is correct.

Thankyou!!

[RazzMeTazz]

The correct answer is A.

But I don't quite understand why 

Explanations would be great

[sparkyblossom]

Do we need to know how to work out the percentage of recombination in linked genes?

[vox nihili]

Do we need to know how to work out the percentage of recombination in linked genes?

God no

[sparkyblossom]

God no

Ha... That's interesting. A lecturer from TSFX said that we need to know how to do it.

[shivaji]

The correct answer is A.

But I don't quite understand why 

Explanations would be great

Possibly because the plant needs to  photosynthesise more than undergo cellular respiration so that it can produce excess glucose which the plant can use as a reactant for cellular respiration. If more respiration occured, then the plant will run out of glucose and this will cause big problems. (plants are autotrophs,  so the only glucose they obtain is through photosynthesis and not diet)

But not quite sure if this is on SD anymore, because the factors influencing rate of photosynthesis is removed, so this maybe removed too?

[anat0my]

Can someone please explain question 2(a) from Unit 4 2009 exam? Thanks!

[vox nihili]

Ha... That's interesting. A lecturer from TSFX said that we need to know how to do it.

TSFX has the unfortunate habit of freaking students out so that they'll keep going to them...then blatantly misrepresenting their achievements with students.

[shivaji]

Can someone please explain question 2(a) from Unit 4 2009 exam? Thanks!

the probability of her being a heterozygote at that gene loci is 4/16 (because the cross is of hererozygote parents at both gene loci), so i 1/4. But for ease, and instead of performing the whole cross, just memorise the 9:3:3;1 rule, and that 4 out of the 16 will be heterozygous at both gene loci, 2 homozygous dominant at one gene loci and hereterozygous as the other, and 1 homozygous dominant at both gene loci

[RazzMeTazz]

Possibly because the plant needs to  photosynthesise more than undergo cellular respiration so that it can produce excess glucose which the plant can use as a reactant for cellular respiration. If more respiration occured, then the plant will run out of glucose and this will cause big problems. (plants are autotrophs,  so the only glucose they obtain is through photosynthesis and not diet)

But not quite sure if this is on SD anymore, because the factors influencing rate of photosynthesis is removed, so this maybe removed too?

Ohhh okay that makes sense. For some reason I thought increased rate of photosynthesis would have to occur (more glucose) for flowering etc since its spring and thus to use this glucose increased rate of cellular respiration too. But yes if that occurred the plant would run out of glucose!

Oh yeah true. Goodpoint!