VCE Biology Question Thread

[geminii]

Not sure if this is beyond the scope of VCE Biology or not, but I'm a bit confused about dominant and recessive traits.

I get that if you have a father with brown hair and a mother with blonde hair, where both are homozygous, there is a 100% chance you will have a brown haired child.
If the father is heterozygous dominant for brown hair while the mother has blonde hair and is therefore homozygous recessive, there is a 50% chance of a blonde child and a 50% chance of a brown-haired child.

But, what happens if you have a blonde father and a red-haired mother, or vice versa? Both the traits are recessive! 
Same with a father with blue eyes and a mother with green eyes. Can anyone say what happens then?

[AhNeon]

Can anyone explain the involvement of electrons in photosynthesis and aerobic respiration. How much of it do we need to know, cos some of these practise papers ask some pretty specific things,

[Gogo14]

Can anyone explain the involvement of electrons in photosynthesis and aerobic respiration. How much of it do we need to know, cos some of these practise papers ask some pretty specific things,

Photosynthesis-  chlorophyll uses light to split water and essentially steal the electrons from it. These electrons are passed along a series of membrane proteins (electron acceptors) that allows a hydrogen ion gradient to occur through hydrogen pumps. This then allows carrier molecules to be "loaded" e.g. NADPH, and ATP is formed by passing H ions through ATPsynthase.
Aerobic respiration- similar process but acceptor molecules like NADH are dumping electrons into the membrane proteins (cytochromes) where oxygen is the final electron acceptor and combines with H ions to form water.

Dont need to know in detail for the exam, Ive only ever come across a question requiring knowledge like that when they ask you to describe the ETC, and that was a 2 or 3 mark q

It would be great if someone could answer the qs i posted thnx

[n.a]

Are questions like the VCAA 2006 Exam 1 Questions 3b and c MCQ still part of the study design?

[AhNeon]

1. Why can there be only 2 forms of a gene in any one cell?
2. How can you exhibit genetic characteristics that neither your mother nor father show?
Was thinking recessive traits but the word genetics threw me off. Mutations?
3. In snapdragons, red allele flower colour(R) and white flower colour (R') combine to prodyce pink flowers (RR'). Why do you have to use these kinds of letters shown?
4. Red cattle(RR) white cattle(WW) produces both red and white coloured cattle (RW). Why do you have to use the kinds of letters shown?

Thanks for that electron stuff!
1.there are 2 homologous chromsomes in a cell. As each one carries the same gene, there are two forms of a gene in each cell.
2. Well there are a number of ways this can happen. For example, a mutation in one of the gametes prior to fertilisation.
3. If the question defines your symbols, then you should just go with what your'e given. This specific event is an example of incomplete dominance (which i'm pretty sure has been removed from the course)
4. Same as number 3. However, this is codominance and thus the alleles are shown with a superscript (for example blood type A means that the person has the genotype I^A)
Hope i got what you meant for each question

[vox nihili]

Not sure if this is beyond the scope of VCE Biology or not, but I'm a bit confused about dominant and recessive traits.

I get that if you have a father with brown hair and a mother with blonde hair, where both are homozygous, there is a 100% chance you will have a brown haired child.
If the father is heterozygous dominant for brown hair while the mother has blonde hair and is therefore homozygous recessive, there is a 50% chance of a blonde child and a 50% chance of a brown-haired child.

But, what happens if you have a blonde father and a red-haired mother, or vice versa? Both the traits are recessive! 
Same with a father with blue eyes and a mother with green eyes. Can anyone say what happens then?

They're polygenic traits. So there's more than one gene that determines hair colour, not just one gene and then the typical dominant recessive kind of set up.
You are expected to know about polygenic traits for the purpose of your exam, and your question is one they could reasonably ask.

Are questions like the VCAA 2006 Exam 1 Questions 3b and c MCQ still part of the study design?

You'll likely have more luck getting an answer if you attach those questions.

[Steph.Y]

Do u mean like
- Variation
- Selection features
ect?

haha yep! sorry for not making that clear 

[n.a]

You'll likely have more luck getting an answer if you attach those questions.

Okay, here they are.

So would these kinds of questions still be applicable to the study design bc I couldn't find any mention of them on the study design.

Thanks 😊

[vox nihili]

Okay, here they are.

So would these kinds of questions still be applicable to the study design bc I couldn't find any mention of them on the study design.

Thanks 😊

It would be a hard question, but it's reasonable. Rational drug design is still on the course.

[n.a]

It would be a hard question, but it's reasonable. Rational drug design is still on the course.

Thank you, and sorry to be a bother, but even the question asking you to design an experiment?

[vox nihili]

Thank you, and sorry to be a bother, but even the question asking you to design an experiment?

Absolutely, yep

[Hayley_turnham]

What percentage should we be roughly getting on vcaa practice exams if aiming for a 40+ study score

I understand its dependent on the whole state and rankings etc but is there any rough guide? I dont know if Im doing well or not
Thanks

[vox nihili]

What percentage should we be roughly getting on vcaa practice exams if aiming for a 40+ study score

I understand its dependent on the whole state and rankings etc but is there any rough guide? I dont know if Im doing well or not
Thanks

If you google your exam year and "grade distributions vcaa" you can work out your exam grade for that year. You should be aiming for an A+

[Hayley_turnham]

If you google your exam year and "grade distributions vcaa" you can work out your exam grade for that year. You should be aiming for an A+

e.g. 2014 for an A+ says 192 - 220
Im not quite sure what that actually means
our exam mark is out of 110?

[Sine]

e.g. 2014 for an A+ says 192 - 220
Im not quite sure what that actually means
our exam mark is out of 110?

exams are double marked so you will end up with a score /220 (110 x 2 =220) usually it won't mean much but in a subject like biology half marks are quite common (when one examiner gives you a mark and the other doesn't). Just double what score you get and then check the grade distributions