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How did everyone find it? Any guesses at the grade boundaries?
Really hope lysosomes is acceptable for Q1- Put centrioles then crossed it out later -.-
Looking at the unofficial answers I reckon I dropped about 9 marks tops, which I'm happy with :smile:
Any ideas on what 40/60 marks would be? :frown:
I'm so gutted about some of the stupid mistakes I made...
Also is unit 2 worth 50% of the overall AS?
If I get an A in unit 2, a low A in my ISA and a high B in unit 1, would there be any chance I could get an A overall? I'm so stressed now!!!

Thank you! :smile:
(edited 9 years ago)
Original post by Zippyzazu
Any ideas on what 40/60 marks would be? :frown: I'm so gutted about some of the stupid mistakes I made... l
Also is unit 2 worth 50% of the overall AS?

Thank you!


Yes, unit 2 is worth 50% 150/300 UMS
Unit 1 is 30% 90/300 UMS
Rest is the practical skills...
For tidal volume I wrote 'the amount of air that is breathed in and out in one breath at rest. It is usually 0.5dm3'

Would I get 0,1 or 2 marks? Amount isn't quite as precise as volume, and I didn't say in the lungs?
Original post by charlotte_3008
For the breathing/balloons one, about how the teacher could demonstrate, I talked about breathing into the glass tube at the top of the apparatus not about pulling the rubber thing down.. Do you reckon this totally wrong?? :frown:

I did exactly the same thing! Anyone know?
Original post by Jack873
Ahh fair enough! Does a proton gradient only apply to the electron transport chain in aerobic respiration? I wasn't sure!


I believe so. It may still be on the mark scheme though :smile:

Original post by Nandosfood
For 1)a)i) I put vacuoles - that is accepted too, right?

Also just remembered there was one question before the definitions asking what the microscope could see in companion cells :smile:


Should be - it's a 'structure'.
And fixed :smile:

Original post by Itsmeitsmeitsme
I think you've missed the one that asked what would a scientist see if he looked at the sieve tube element and companion cell through an electron microscope


Fixed.

Original post by Cone
Is Vacuole accepted for the first Q

For the electron microscope question I wrote it allows you to see the mitochondria. Which shows that it is an active process requiring ATP and therefore it uses ATP in active transport.
You could also say that ribosomes can be seen which make co- transport proteins


Posted from TSR Mobile


Should be.
That's not quite worded right - you should've said that there were many mitochondria in the companion cells. But that should get some credit, you've got the right idea.

Original post by lillybeex
I put permanent vacuole instead of chloroplast for the first question, is that right still?


Should be fine.

Original post by Alltimesarah
Did you guys find this harder that june 2013?


Less difficult material, but weirder topics and weirder questions.

Original post by geboers7
I just confirmed glucose is allowed as its produced by rapid photosynthesis and more commonly is converted into sucrose


Is fructose allowed?

Original post by geboers7
June 2013 was ridiculously hard


Agreed.

Original post by Comeback
This (I think it was looking at just the companion cell unless I'm mistaken.

I wrote you would expect to see lots of mitochondria (as ATP is being generated as it is needed for active transport of hydrogen ions). I think it was a 2 or 3 mark question?

Hope this helps OP


It was a 2-marker, and that sounds right :smile: Fixed it now.

Original post by PensiveChicken
How did everyone find it? Any guesses at the grade boundaries?
Really hope lysosomes is acceptable for Q1- Put centrioles then crossed it out later -.-
Looking at the unofficial answers I reckon I dropped about 9 marks tops, which I'm happy with :smile:


Grade boundaries are probably about average. There were no horrible questions that were worth more than 2 marks...but the topics were unusual which will have caught people off guard.

Lysosomes is ambiguous, so they may give you it anyway.
Original post by amcdschool
I did exactly the same thing! Anyone know?


Said this also, looks like its incorrect however.
(edited 9 years ago)
Original post by Zippyzazu
Any ideas on what 40/60 marks would be? :frown:
I'm so gutted about some of the stupid mistakes I made...
Also is unit 2 worth 50% of the overall AS?
If I get an A in unit 2, a low A in my ISA and a high B in unit 1, would there be any chance I could get an A overall? I'm so stressed now!!!

Thank you! :smile:


40/60 is a high B. However, bear in mind that this mark scheme is not comprehensive and you have likely written some things I haven't put that will gain credit. :smile: Unit 2 is 50%, and with those grades an A would seem likely. :smile:

Original post by Comeback
For tidal volume I wrote 'the amount of air that is breathed in and out in one breath at rest. It is usually 0.5dm3'

Would I get 0,1 or 2 marks? Amount isn't quite as precise as volume, and I didn't say in the lungs?


My guess is one mark. :smile:
Original post by Comeback
Said this also. I am sure it is correct and an alternative marking point.


Original post by amcdschool
I did exactly the same thing! Anyone know?


I've already answered this earlier on the thread - I'm sorry, but it's incorrect.
Reply 89
Intsead writing concentration gradient/ steep concentration gradient for the word fill, I put steep diffusion gradient... that should be okay, shouldn't it??
Reply 90
For the what would the scientist see question, would it have been okay to mention many plasmodesmata as that is what the assimilates diffuse through ???
Original post by paradoxicalme
I've already answered this earlier on the thread - I'm sorry, but it's incorrect.


Could you explain why? I've looked back and just found where you said it is incorrect? I agree it was not the preferred answer (and might therefore not be creditable) but there the diagram ocr gave didn't rule it out ?)
(edited 9 years ago)
Reply 92
Im just curious about how is it potentially wrong if you got a person to breathe normally and at rest into the glass tube, I got my A grade buds and they said that was a viable option. As if you try to pull the rubber sheet slightly down and up uniformly, it would be impossible to know to what extent the volume of the tidal volume was accurate. If you had someone breathe into the glass tube and out, it would depict an accurate representation of the tidal volume, as its a similar basis for the mechanism of a spirometer, in that the balloon and chambre are decreasing and increasing with regards to the volume of air inside them.
Guys let us know how you found the exam overall http://www.thestudentroom.co.uk/showthread.php?t=2688453
Reply 94
Original post by geboers7
Im just curious about how is it potentially wrong if you got a person to breathe normally and at rest into the glass tube, I got my A grade buds and they said that was a viable option. As if you try to pull the rubber sheet slightly down and up uniformly, it would be impossible to know to what extent the volume of the tidal volume was accurate. If you had someone breathe into the glass tube and out, it would depict an accurate representation of the tidal volume, as its a similar basis for the mechanism of a spirometer, in that the balloon and chambre are decreasing and increasing with regards to the volume of air inside them.



I forgot to mention the person would be wearing a nose clip or plugging their nose
Original post by J48ble
Intsead writing concentration gradient/ steep concentration gradient for the word fill, I put steep diffusion gradient... that should be okay, shouldn't it??


That'll be fine.

Original post by Grimy
For the what would the scientist see question, would it have been okay to mention many plasmodesmata as that is what the assimilates diffuse through ???


Are the plasmodesmata in the plasma membrane of the companion cells, though? If so, it'll be creditable, but I'm not sure,

Original post by Comeback
Could you explain why? I've looked back and just found where you said it is incorrect? I agree it was not the preferred answer (and might therefore not be creditable) but there the diagram ocr gave didn't rule it out ?)


Original post by geboers7
Im just curious about how is it potentially wrong if you got a person to breathe normally and at rest into the glass tube, I got my A grade buds and they said that was a viable option. As if you try to pull the rubber sheet slightly down and up uniformly, it would be impossible to know to what extent the volume of the tidal volume was accurate. If you had someone breathe into the glass tube and out, it would depict an accurate representation of the tidal volume, as its a similar basis for the mechanism of a spirometer, in that the balloon and chambre are decreasing and increasing with regards to the volume of air inside them.


The reason why I believe it's incorrect is that it wouldn't pragmatically work. We've already discussed that the mechanism works because you pull down the rubber sheet, which increases the volume inside the bell jar, decreasing the pressure and sucking air in down the pressure gradient. Breathing into the tube won't do that, because it's just pushing a little air into the balloons, not changing the volume of the bell jar. The balloons will inflate a tiny bit but they won't demonstrate tidal volume or vital capacity; you'll barely increase the volume of air inside them at all.
Original post by paradoxicalme
That'll be fine.





The reason why I believe it's incorrect is that it wouldn't pragmatically work. We've already discussed that the mechanism works because you pull down the rubber sheet, which increases the volume inside the bell jar, decreasing the pressure and sucking air in down the pressure gradient. Breathing into the tube won't do that, because it's just pushing a little air into the balloons, not changing the volume of the bell jar. The balloons will inflate a tiny bit but they won't demonstrate tidal volume or vital capacity; you'll barely increase the volume of air inside them at all.


I agree now you've explained it, shame but hopefully it won't cost me the A! I've definitely got 40 marks (according to your ms) and then theres some ambiguity about another 5 or so. You sure sound like you're in the running for full UMS (or close to it), fingers crossed!
Was the DIF.DIF in the slime mould question not an example of communication between cells? It's a signalling molecule right?
Does anyone remember what the asexual reproduction question was for the Grex?

I put budding as my answer but everyone else has put mitosis.
Original post by bellend1
Does anyone remember what the asexual reproduction question was for the Grex?

I put budding as my answer but everyone else has put mitosis.


I thought budding was just yeast? I put binary fission; not sure if I got the marks on that one...

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