Login | Register

Welcome, Guest. Please login or register.

July 06, 2020, 03:11:48 pm

Author Topic: VCE Biology Question Thread  (Read 1723607 times)  Share 

1 Member and 3 Guests are viewing this topic.

hbhangu_31

  • Fresh Poster
  • *
  • Posts: 4
  • Respect: 0
Re: VCE Biology Question Thread
« Reply #12705 on: June 30, 2020, 10:39:25 pm »
+1
Also, how did you guys do revision for unit 3 chapters throughout unit 3? In other terms what is your study plan for biology like?

Chocolatepistachio

  • Forum Regular
  • **
  • Posts: 94
  • Respect: +2
Re: VCE Biology Question Thread
« Reply #12706 on: July 01, 2020, 01:47:16 pm »
+2
Why do guanine and cytosine have 3 hydrogen bonds whereas adenine and thymine have 2 hydrogen bonds

1729

  • Trailblazer
  • *
  • Posts: 31
  • The best way to predict the future is to create it
  • Respect: +37
Re: VCE Biology Question Thread
« Reply #12707 on: July 01, 2020, 02:18:02 pm »
+7
Quote from: Quora
Guanine and Cytosine Base pair has three hydrogen bonds,because the exocyclic NH2 at C2 on Guanine lies opposite to,and can hydrogen bond with,a carbonyl at C2 on Cytosine.

In guanine and cytosine you have more nitrogens exposed to more hydrogens which leads to more intermolecular forces (i.e hydrogen bonds)  Furthermore I should add (in case you are not a chemistry student) that nitrogen has a delta negative charge as it is more electronegative and hence attracts electrons more towards it (in a dipole where two covalently bonded atoms have varying electronegativities). Oxygen has a delta negative charge for similar reasons. However, hydrogen has a delta positive charge as it is more electropositive, and hence lets its electrons be closer to the other covalently bonded atom, in this case, nitrogen. Opposite charges attract.
« Last Edit: July 01, 2020, 10:28:08 pm by 1729 »
Spoiler
If you are wondering about my avatar, It was inspired by a problem I did which asked me to prove that the graphs of xy = 1 and y^2 = x^2 + 2 intersected at a 90 degree angle. The resulting figure in the middle kinda like a 8-sided square in hyperbolic space. It also resembles the conformal map of the complex square root.

Subjects: EngLang, Lit, Methods, Spesh, Chemistry, Biology, Physics.

Goals: 95+ ATAR | Medical Course MelbUni | Doctor

Chocolatepistachio

  • Forum Regular
  • **
  • Posts: 94
  • Respect: +2
Re: VCE Biology Question Thread
« Reply #12708 on: July 01, 2020, 02:41:26 pm »
0
How would you answer this question/ what would you need to include for 4 marks.
Using examples explain why sex linkage and co-dominance do not produce simple Mendelian ratios

Sine

  • National Moderator
  • ATAR Notes Legend
  • *****
  • Posts: 4238
  • ARTWORK 23
  • Respect: +1344
Re: VCE Biology Question Thread
« Reply #12709 on: July 01, 2020, 03:13:00 pm »
+4
How would you answer this question/ what would you need to include for 4 marks.
Using examples explain why sex linkage and co-dominance do not produce simple Mendelian ratios
Just guessing on the mark scheme but I would go with
1 mark - definition/explanation of what mendelian ratios are
2 marks - explanation
1 mark - including an example

Chocolatepistachio

  • Forum Regular
  • **
  • Posts: 94
  • Respect: +2
Re: VCE Biology Question Thread
« Reply #12710 on: July 01, 2020, 03:53:20 pm »
0
would this be correctly labelled

Sine

  • National Moderator
  • ATAR Notes Legend
  • *****
  • Posts: 4238
  • ARTWORK 23
  • Respect: +1344
Re: VCE Biology Question Thread
« Reply #12711 on: July 01, 2020, 04:13:16 pm »
+5
would this be correctly labelled
Some of it is a bit unclear as to what the labels are pointing exactly to but you seem to have labelled in the generally correct areas.
Some potential fixes would be that the IVC and SVC both drain to the right atrium (but don't really come together themselves).

Chocolatepistachio

  • Forum Regular
  • **
  • Posts: 94
  • Respect: +2
Re: VCE Biology Question Thread
« Reply #12712 on: July 01, 2020, 04:39:49 pm »
0
Does the X chromosome undergo crossing over

Owlbird83

  • Forum Obsessive
  • ***
  • Posts: 266
  • Respect: +274
Re: VCE Biology Question Thread
« Reply #12713 on: July 01, 2020, 07:02:22 pm »
+1
Does the X chromosome undergo crossing over

Crossing over occurs normally between x-chromosomes. When there's x and y it only occurs in a small place called the pseudoautosomal region that is like an autosomal part and are homologous between the x and y.
2018: Biology
2019: Chemistry, Physics, Math Methods, English, Japanese
2020: Bachelor of Psychology (Monash)

Chocolatepistachio

  • Forum Regular
  • **
  • Posts: 94
  • Respect: +2
Re: VCE Biology Question Thread
« Reply #12714 on: July 01, 2020, 10:37:32 pm »
+1
Thanks!

Does non random mating introduce variation into a population

Whatís Telocentric and metacentric chromosomes?

Azila2004

  • Adventurer
  • *
  • Posts: 22
  • Respect: 0
Re: VCE Biology Question Thread
« Reply #12715 on: July 01, 2020, 10:48:58 pm »
+1
Hello!

I have a question: For example, when describing some of the reasons for apoptosis and other things, why do you always have to write viral infection rather an infection through protozoa or such? I understand you have to be specific, but why specifically viral infections? I saw in VCAA answers that only viral infections are included.

Thanks :)
Just someone who likes to learn a lot of questions.

Aspiring medical practitioner! ʕḗᴥḕʔっ

Owlbird83

  • Forum Obsessive
  • ***
  • Posts: 266
  • Respect: +274
Re: VCE Biology Question Thread
« Reply #12716 on: July 01, 2020, 10:57:52 pm »
+4
Thanks!

Does non random mating introduce variation into a population

Whatís Telocentric and metacentric chromosomes?
It can both increase and decrease variation.
For example, when animals choose to mate with other animals who are similar to them, it decreases variation, but when the species tends to mate with others who are more different from them, then it leads to more variation.
( I'm pretty sure it's mostly decreasing variation though, because when like colourful male birds are more attractive to the females, after generations, most of the male birds then end up colourful because they are picked to mate with).
Edit: I might be wrong, I think it might only decrease genetic variation
Edit2: I just went to bed and started thinking about it, and non random mating would decrease variation, it wouldn't increase it. (correct me if I'm wrong anyone)

Telocentric chromosomes have their centromeres at the end of the chromosomes, metacentric chromosomes have the centromere at the centre of the chromosomes.
« Last Edit: July 01, 2020, 11:19:56 pm by Owlbird83 »
2018: Biology
2019: Chemistry, Physics, Math Methods, English, Japanese
2020: Bachelor of Psychology (Monash)

1729

  • Trailblazer
  • *
  • Posts: 31
  • The best way to predict the future is to create it
  • Respect: +37
Re: VCE Biology Question Thread
« Reply #12717 on: July 02, 2020, 09:59:02 am »
+6
Thanks!

Does non random mating introduce variation into a population

Whatís Telocentric and metacentric chromosomes?
I don't think you should be asking googleable questions here such as your last question and in regards to your first question it kind of depends by selecting (for example) for individuals with similar genotypes, you can end up with inbreeding which results in a narrower gene pool however by selecting for individuals with different genotypes (this is fittingly called outbreeding) you can actually increase the variation of the gene pool, introducing greater genetic variation among the population. And Non random mating (correct me if im wrong) will still show variation as there will be allelic recombination within gametes, however keep in mind (correct me if im wrong) that genetic variation from recombination has a much lesser impact than inbreeding/outbreeding.
Edit: I might be wrong, I think it might only decrease genetic variation
Edit2: I just went to bed and started thinking about it, and non random mating would decrease variation, it wouldn't increase it. (correct me if I'm wrong anyone)
It depends on what sort of non-random mating inbreeding vs outbreeding.
Spoiler
If you are wondering about my avatar, It was inspired by a problem I did which asked me to prove that the graphs of xy = 1 and y^2 = x^2 + 2 intersected at a 90 degree angle. The resulting figure in the middle kinda like a 8-sided square in hyperbolic space. It also resembles the conformal map of the complex square root.

Subjects: EngLang, Lit, Methods, Spesh, Chemistry, Biology, Physics.

Goals: 95+ ATAR | Medical Course MelbUni | Doctor

Chocolatepistachio

  • Forum Regular
  • **
  • Posts: 94
  • Respect: +2
Re: VCE Biology Question Thread
« Reply #12718 on: July 02, 2020, 02:08:21 pm »
+1
Ok thanks

Why canít 33 electrons be produced in the electron transport chain

1729

  • Trailblazer
  • *
  • Posts: 31
  • The best way to predict the future is to create it
  • Respect: +37
Re: VCE Biology Question Thread
« Reply #12719 on: July 02, 2020, 07:06:47 pm »
+3
Why canít 33 electrons be produced in the electron transport chain
ETC is a transport chain I don't think it produces any electrons and I also don't think it had a limit but it does cap when there's no oxygen. Excited electrons pass through the ETC (going crazy and then losing its energy), but if I recall correctly, the ETC doesnt produce any of its own.
Spoiler
If you are wondering about my avatar, It was inspired by a problem I did which asked me to prove that the graphs of xy = 1 and y^2 = x^2 + 2 intersected at a 90 degree angle. The resulting figure in the middle kinda like a 8-sided square in hyperbolic space. It also resembles the conformal map of the complex square root.

Subjects: EngLang, Lit, Methods, Spesh, Chemistry, Biology, Physics.

Goals: 95+ ATAR | Medical Course MelbUni | Doctor