Biology Exam Discussion (and suggested answers!)

[DalvinT]

Lol 95 for a band 6?, its gonna be more like a 83-84

Most likely lol

[Merin Thomas]

Hey hey heyyyyy XD thanks for the reply (: idk how this system works :/ so when they say for example band 6 cut off is 95, do they mean raw mark of 95 0.0 Im soooo lossstttt 0.0 .

[DalvinT]

No worries
I think it’s based off raw first. I’m not entirely sure, but my thinking is that , if an exam was hard and let’s say the highest mark of that was 85(top 0.15% of the scores). This means the data would be positively skew, which results in the scores to shift upwards to be more normally distributed (bell shape)... so those who got 85 will probably get like 90+ now.

[inescelic]

Guys for the crossing over question, is it the G's that cross over? That's what I gathered from that 2001 MC. How can it be A and B because then you will get multiple combinations as genes cross over independently of all other genes i.e. a allele won't necessarily cross over with b allele. I got ABG ABg abG abg? Is that the same as  ABG abG ABg abg?

[inescelic]

Thoughts for raw band 6 cut off?

[samuel.bartlett]

For question 19 in multiple choice, wasn't 53 the total haploid number, making the total diploid number of the chromosomes 106?

[Natasha.97]

For question 19 in multiple choice, wasn't 53 the total haploid number, making the total diploid number of the chromosomes 106?

Hi!

One parent had 44 chromosomes, the other had 62. Half of the genetic information from parent 1 (22) is added to half of the genetic information from parent 2 (31) which makes the diploid number 53.

[DalvinT]

Guys for the crossing over question, is it the G's that cross over? That's what I gathered from that 2001 MC. How can it be A and B because then you will get multiple combinations as genes cross over independently of all other genes i.e. a allele won't necessarily cross over with b allele. I got ABG ABg abG abg? Is that the same as  ABG abG ABg abg?

The crossing over point indicates that the alleles above it, only cross . The G/g alleles and ABG of first set of homologous chromosome (most left one) and abg of Second set of homologous chromosomes (most Right) don’t have it , therefore they do not cross.
Thus, only producing ABG**, (ab)G, (AB)g, abg** once crossed over.

* brackets () - indicate the alleles that have exchanged/crossed over
** - these stay the same due to no available crossing over point.

Hope that makes sense

[DalvinT]

For question 19 in multiple choice, wasn't 53 the total haploid number, making the total diploid number of the chromosomes 106?

Hey there!
What Jess has said is correct!!
I immediately thought about Mendel, Sutton and Boveri’s discoveries and what understandings they’ve given us about inheritance, then applied it to the question.
This one was definitely a high order question!

[pikachu975]

(Image removed from quote.)

They’ve recycled the question lol.
 I wrote
Before - ABG, ABG, abg , abg
After - ABG, abG, ABg, abg

Nah before is not that because those are the replicated chromosomes (92 chromosomes) when the genotype should be 46


Also rip we didn't learn that you should cross above the line

[pvee123]

Since my estimated mark is 74 (Im so disappointed, lost so much marks for misreading questions), does it get scaled at all (since the exam was quite easy)? Would this be an early band 4? Have I failed biology??

[DalvinT]

Nah before is not that because those are the replicated chromosomes (92 chromosomes) when the genotype should be 46


Also rip we didn't learn that you should cross above the line

Sameee I didn’t too! (
But I was lucky to have come across this question the day before and figured it out my self !

[DalvinT]

Since my estimated mark is 74 (Im so disappointed, lost so much marks for misreading questions), does it get scaled at all (since the exam was quite easy)? Would this be an early band 4? Have I failed biology??

Same, my short answers were atrocious! But my mcq and options were okay.

No, I don’t think you will fail biology! I’m sure you did fineee, we really don’t know whether we did well or not.
And remember , there are many factors that count to moderating and scaling. Not only how well the state did

[pikachu975]

Sameee I didn’t too! (
But I was lucky to have come across this question the day before and figured it out my self !

Oh rip so far I've lost 2 on MCQ and 2 on short answer hopefully that's it because aligning won't be that high this year

[DalvinT]

Oh rip so far I've lost 2 on MCQ and 2 on short answer hopefully that's it because aligning won't be that high this year

Same got 18 for mcq
Probably lost 5-8 marks for short answers