iber2011 Posted May 21, 2011 Report Share Posted May 21, 2011 (edited) what was the real size of the cell in paper 2 section A ?? i got 27 or something Edited May 21, 2011 by iber2011 Reply Link to post Share on other sites More sharing options...
Alex1307 Posted May 21, 2011 Report Share Posted May 21, 2011 what was the real size of the cell in paper 2 section A ?? i got 27 or something I didn't have my freaking calculator, but I found something like 6nm haha... Reply Link to post Share on other sites More sharing options...
I`m Potato Posted May 21, 2011 Report Share Posted May 21, 2011 (edited) I forgot, but something like 7 micrometers. (not sure) But isn't that a little too large for an organelle size? But I double checked and I still got the same answer... Oh wait. It should be fine. A mitochondrion can have sizes varying from 0.5-10 micrometers. Edited May 21, 2011 by I`m Potato Reply Link to post Share on other sites More sharing options...
Alex1307 Posted May 21, 2011 Report Share Posted May 21, 2011 I forgot, but something like 7 micrometers. (not sure) But isn't that a little too large for an organelle size? But I double checked and I still got the same answer... Oh wait. It shouldb efine. A mitochondrion can have sizes varying from 0.5-7 micrometers. Oh **** you're right! My answer was 6000 nanometers, so 6 micrometers... ugh I'm pissed Oh well! That was only one question. Oh btw what did you guys write for the "label the mitochondrion" question? Was 1 cristae or inner membrane space? Reply Link to post Share on other sites More sharing options...
Joanna C Posted May 21, 2011 Report Share Posted May 21, 2011 I forgot, but something like 7 micrometers. (not sure) But isn't that a little too large for an organelle size? But I double checked and I still got the same answer... Oh wait. It shouldb efine. A mitochondrion can have sizes varying from 0.5-7 micrometers. Oh **** you're right! My answer was 6000 nanometers, so 6 micrometers... ugh I'm pissed Oh well! That was only one question. Oh btw what did you guys write for the "label the mitochondrion" question? Was 1 cristae or inner membrane space? I'm pretty sure 6 micrometers / 6000 nanometers was the right answer - that's what everyone in my class got, although I somehow got 600 nanometers (think I might have typed it into the calculator wrong or something ) For the mitochondrion question I got cristae. Was the line pointing to the middle of the cristae then? I didn't think of that. That would have been a bit mean though! Reply Link to post Share on other sites More sharing options...
Joanna C Posted May 21, 2011 Report Share Posted May 21, 2011 What did people put for the homologous characteristics question in paper 1? Was it the appendix in humans and horses? I didn't put that though, I put the fin of a fish and wing of a bird - complete guess.Also, what's this question about the spongy mesophyll layer? I have no recollection of this whatsoever!The section B questions this year were so much better than last year's (which were really obscure..) I did 5 and 6 - thought it'd at least be quite easy to match the markscheme for the 9 mark Calvin cycle question - let's face it, in biology it's all about being able to predict the markschemes/read the examiner's mind!Speaking of reading the examiner's mind, the question about nutrients and energy was pretty confusing - I guessed that they were looking for us to say that nutrients are recycled (helped by saprotrophs) whereas energy is all ultimately lost as heat (because there was a syllabus point about that).. the question was confusingly worded if they were asking that though. Reply Link to post Share on other sites More sharing options...
I`m Potato Posted May 21, 2011 Report Share Posted May 21, 2011 What did people put for the homologous characteristics question in paper 1? Was it the appendix in humans and horses? I didn't put that though, I put the fin of a fish and wing of a bird - complete guess.Also, what's this question about the spongy mesophyll layer? I have no recollection of this whatsoever!The section B questions this year were so much better than last year's (which were really obscure..) I did 5 and 6 - thought it'd at least be quite easy to match the markscheme for the 9 mark Calvin cycle question - let's face it, in biology it's all about being able to predict the markschemes/read the examiner's mind!Speaking of reading the examiner's mind, the question about nutrients and energy was pretty confusing - I guessed that they were looking for us to say that nutrients are recycled (helped by saprotrophs) whereas energy is all ultimately lost as heat (because there was a syllabus point about that).. the question was confusingly worded if they were asking that though.Homologous characteristics, I put appendix in horse and humans (but I have a huge feeling that it's the fin of a fish and wing of a bird).Spongy mesophyll, I put alveoli (or whatever that was related to the lung), because it is the site for gas exchange in plants.About the energy/nutrient question, I was thinking of energy is lost but actually I rethinked twice because energy doesn't actually get 'lost'. It is just being transferred to another state and perhaps leaves the food chain/web onto another place. So it is ultimately 'recycled' but not as immediate as nutrient I guess... That's what I wrote. Reply Link to post Share on other sites More sharing options...
gkong Posted May 21, 2011 Report Share Posted May 21, 2011 Oh btw what did you guys write for the "label the mitochondrion" question? Was 1 cristae or inner membrane space?For the mitochondrion question I got cristae. Was the line pointing to the middle of the cristae then? I didn't think of that. That would have been a bit mean though!I wrote intermembrane space just because of the question after, something about the adaptation relating to its function?Also, what's this question about the spongy mesophyll layer? I have no recollection of this whatsoever!I wrote that it was similar to alveoli, because thats where cell resp occurs. Reply Link to post Share on other sites More sharing options...
Alex1307 Posted May 21, 2011 Report Share Posted May 21, 2011 The section B questions this year were so much better than last year's (which were really obscure..) I did 5 and 6 - thought it'd at least be quite easy to match the markscheme for the 9 mark Calvin cycle question - let's face it, in biology it's all about being able to predict the markschemes/read the examiner's mind!I totally agree! The markscheme is so random sometimes it's really hard to actually guess what the marker wants you to write...But yeah for the light independent reaction it was pretty obvious what they were asking for. However, for the vaccination (or even sickle cell anemia) question it was a little bit harder to guess what's going to be in the markscheme. Reply Link to post Share on other sites More sharing options...
Joanna C Posted May 21, 2011 Report Share Posted May 21, 2011 The section B questions this year were so much better than last year's (which were really obscure..) I did 5 and 6 - thought it'd at least be quite easy to match the markscheme for the 9 mark Calvin cycle question - let's face it, in biology it's all about being able to predict the markschemes/read the examiner's mind! I totally agree! The markscheme is so random sometimes it's really hard to actually guess what the marker wants you to write... But yeah for the light independent reaction it was pretty obvious what they were asking for. However, for the vaccination (or even sickle cell anemia) question it was a little bit harder to guess what's going to be in the markscheme. Exactly yup that's why I didn't do question 8! The transpiration one in question 6 was easy to predict (hopefully) too - I'm guessing one mark for defining transpiration, then state and explain effect of humidity, wind, light and temperature for 2 marks each? Well that's what I'd guess anyway! And ah yes, I remember the spongy mesophyll question now. Yeah, I put alveoli because it's a surface for gas exchange. OKAY... I just googled horse's appendix, and from what I can tell... Horses don't even have an appendix!? If that's true, then that question was a bit of a joke! Reply Link to post Share on other sites More sharing options...
lighthuntz0r Posted May 22, 2011 Report Share Posted May 22, 2011 I got 0.6 micrometers for the drawing.It's bird wing and fish pin for sure on that MC.Cristae/inter-membrane space should both be correct answers unless the line went to the membrane but not to the center (i don't remember). Cristae is for sure a correct answer.Causes of sickle cell anemia was a weird question(for 9 points if I remember well). It was hard for me to come up with all those marking points :/ Reply Link to post Share on other sites More sharing options...
Hypnotica Posted May 24, 2011 Report Share Posted May 24, 2011 (edited) Hey guys for the energy question it should, according to IB's own syllabus, be "energy can freely enter and leave an ecosystem (in the form of light, wastes) but nutrients must be recycled, making decomposers a necessary component of an ecosystem" (my own words btw). I think fins and wings are homologous but idk for sure, also got 6 micrometers for the mitochondria Edited May 24, 2011 by Hypnotica Reply Link to post Share on other sites More sharing options...
I`m Potato Posted May 24, 2011 Report Share Posted May 24, 2011 (edited) Hey guys for the energy question it should, according to IB's own syllabus, be "energy can freely enter and leave an ecosystem (in the form of light, wastes) but nutrients must be recycled, making decomposers a necessary component of an ecosystem" (my own words btw). For the homologous structures question, it should be the wings of an insect and a bird - they might not seem related but they are...too long to explain just Google it So would it be correct to say that "energy can be lost to the outside of the food web as many forms (i.e. not locally recycled) whereas nutrients is immediately recycled by decomposers within the same food web"? That's what I wrote... But I also mentioned that energy is also recycled because energy cannot be made nor destroyed so it has to be somewhat "recycled"? Edited May 24, 2011 by I`m Potato Reply Link to post Share on other sites More sharing options...
Hossam Ayad Posted August 21, 2011 Report Share Posted August 21, 2011 I think they were looking for primarily on a discussion for the clonal selection and the challenge and response principles. That's what pops up in my mind when I saw the question in the exam. Other than that I don't see what else you can write about...Oh, and the primary and secondary responses? But for that there isn't really much to write about isn't it.Well, I guess we just have to wait for the markscheme to find out what they really expected.What about the 8(a) question? The role of the skin in regulating body temperature? We needed to talk about homeostatic control right? And sweat and hair and skin arterioles contracting/dilating?hey can u send me tehe paper and marckscheme or upload link Reply Link to post Share on other sites More sharing options...
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