Bio HL Papers 1 & 2 May 2010

[TNT]

What was the monocotyldon or diccotyldon question was the answer like II and III

[Dzeb]

No, it was I and III. The question asked for characteristics of monocots.

I - parallel leave vessels

II - organs with multiples of 4

III - Lateral root system (or fibrous, not sure)

I is definitely correct and II is wrong since monocots had multiples of 3. There was no answer I only hence it was I and III only.

[dexter]

Parallel veins and fibrous roots and NOT floral multiple of four!

[dexter]

Tropism 8 marks! Down Syndrome 8 marks. Can anyone try to draw up a mark scheme? like what to write for those 8 marks? I felt that the marks were too much!

[Dzeb]

Well, Down syndrome can actually have 8 points. You have to go over a part of meiosis (Metaphase II and Anaphase II, these could make 3 or even 4 points) to explain how the chromosomes should separate. Then you explain non-disjunction which leads to gametes with unequal numbers of chromosomes. The fusion of the gamete with two 21st chromosomes with a healthy gamete will lead to a zygote with three 21st chromosomes =]

And I did not do tropism because I know very little about plants. But you have to state what tropism is, outline the role and function of auxin and several theories of what effect does auxin have on the tropism

Edited May 18, 2010 by Dzeb

[pomoni]

Thank God about the detritus (or whatever it's called) one.. I changed it in the last second!

But I got the one with monocotolydons wrong

And I'm pretty sure for that absorption diagram the answer was colon. I'd never heard this word before, but on the diagram the white arrows were like 4 around the colon so I'm sure this was the answer (I would be very surprised if it was not)

What's the answer for the phyla of plants? I put coniferophyta but I think it's wrong. What did you put??

I actually liked the analysis part a lot!!!!

But I messed up in section B. I chose the glycolysis question and the down syndrome one. For the glycolysis one when you had to talk about regulation of glucose levels I mixed up the terminology and for the down syndrome one I had to get creative and just write what I thought was right... section B was so annoying. I wish they got questions like last year!

Edited May 18, 2010 by pomoni

[dexter]

Thank God about the detritus (or whatever it's called) one.. I changed it in the last second!

But I got the one with monocotolydons wrong

And I'm pretty sure for that absorption diagram the answer was colon. I'd never heard this word before, but on the diagram the white arrows were like 4 around the colon so I'm sure this was the answer (I would be very surprised if it was not)

What's the answer for the phyla of plants? I put coniferophyta but I think it's wrong. What did you put??

I actually liked the analysis part a lot!!!!

But I messed up in section B. I chose the glycolysis question and the down syndrome one. For the glycolysis one when you had to talk about regulation of glucose levels I mixed up the terminology and for the down syndrome one I had to get creative and just write what I thought was right... section B was so annoying. I wish they got questions like last year!

Filicinophtye. It has roots and has no confiers nor flowers.

Edited May 18, 2010 by dexter

[Aquarius]

Thank God about the detritus (or whatever it's called) one.. I changed it in the last second!

But I got the one with monocotolydons wrong

And I'm pretty sure for that absorption diagram the answer was colon. I'd never heard this word before, but on the diagram the white arrows were like 4 around the colon so I'm sure this was the answer (I would be very surprised if it was not)

What's the answer for the phyla of plants? I put coniferophyta but I think it's wrong. What did you put??

I actually liked the analysis part a lot!!!!

But I messed up in section B. I chose the glycolysis question and the down syndrome one. For the glycolysis one when you had to talk about regulation of glucose levels I mixed up the terminology and for the down syndrome one I had to get creative and just write what I thought was right... section B was so annoying. I wish they got questions like last year!

Filicinophtye. It has roots and has no confiers nor flowers.

Yeah the picture obviously shows ferns.

Moreover about the water absorption it should be small intestine instead since about 8000ml of water is absorbed there. The main function of colon is absorption of water but not necessarily the main site to do so!

[pomoni]

For the chemiosmosis one did you put "A"? Coupling of ATP with electron transport (blabla..) ? Is that correct?

EDIT:

By the way for the question about water being a good coolant, is it okay to mention the covalent bonds only? I didn't talk about hydrogen bonds between the water molecules.

OH and for the labeling the gene transfer, I named the first cell as donor and the last and host. And the circular thing as "vector" and the third as DNA. Can anyone tell me if that's true?

Edited May 18, 2010 by pomoni

[Dzeb]

Chemiosmosis is the movement of H+ ions down the concentration gradient. And the answer was formulated almost exactly like this.

Covalent bonds in water molecules have nothing to do with being a good coolant. It is a good coolant due to high specific heat (a lot of energy is required to heat it) and due to high temperature of vaporization because of hydrogen bonds between molecules. As a result, water absorbs a lot of energy before it can evaporate.

Also, the reason why it is very cold when you get out of the water is hydrogen bonds. Any water blown by wind or any molecules that evaporate break hydrogen bonds and absorb the energy from the body.

[x___x]

Thank God about the detritus (or whatever it's called) one.. I changed it in the last second!

But I got the one with monocotolydons wrong

And I'm pretty sure for that absorption diagram the answer was colon. I'd never heard this word before, but on the diagram the white arrows were like 4 around the colon so I'm sure this was the answer (I would be very surprised if it was not)

What's the answer for the phyla of plants? I put coniferophyta but I think it's wrong. What did you put??

I actually liked the analysis part a lot!!!!

But I messed up in section B. I chose the glycolysis question and the down syndrome one. For the glycolysis one when you had to talk about regulation of glucose levels I mixed up the terminology and for the down syndrome one I had to get creative and just write what I thought was right... section B was so annoying. I wish they got questions like last year!

Filicinophtye. It has roots and has no confiers nor flowers.

Yeah the picture obviously shows ferns.

Moreover about the water absorption it should be small intestine instead since about 8000ml of water is absorbed there. The main function of colon is absorption of water but not necessarily the main site to do so!

i don't think it's the small intestine, because (i think) the numbers represent how much water is left, not how much water is absorbed. That's why the number is small in the colon compared to other parts like small intestine. when you see it like this, the diagram actually makes sense.

[x___x]

For the chemiosmosis one did you put "A"? Coupling of ATP with electron transport (blabla..) ? Is that correct?

EDIT:

By the way for the question about water being a good coolant, is it okay to mention the covalent bonds only? I didn't talk about hydrogen bonds between the water molecules.

OH and for the labeling the gene transfer, I named the first cell as donor and the last and host. And the circular thing as "vector" and the third as DNA. Can anyone tell me if that's true?

well, for the chemiosmosis i had it as A, not sure though. i guess it's right, 'cause it's the only answer that gives the full picture, it said something like: coupling of ATP synthesis with the electron transport and hydrogen ion movement...

sorry to say that , but it has nothing to do with covalent bonding, since we're talking about evaporation, thus the intramolecular forces, which means hydrogen bonding between two neighboring water molecules.

oh my god! i messed everything up in the gene transfer question, i wrote the first cell as bacterium , the last as "recombinant-plasmid bacterium" ... NO!

the circular thing is plasmid, the third is DNA fragment, as far as i know. Not sure though. couldn't they bring us something more obvious to label? uh!

Edited May 18, 2010 by x___x

[x___x]

Can anyone please discuss the data-based questions. i felt stupid while solving (trying to solve!). i couldn't make any sense out of the data given.

[pomoni]

As far as I remember the given was about bird's eating of food from 2 different sites, site 1 and site 2. There were 4 bird species. And they gave u a graph with the amount of food eaten and a table with the average biomass or something like that.. i forgot what it was.

Which question exactly are you unsure of? Please remind me of the questions..

[x___x]

As far as I remember the given was about bird's eating of food from 2 different sites, site 1 and site 2. There were 4 bird species. And they gave u a graph with the amount of food eaten and a table with the average biomass or something like that.. i forgot what it was.

Which question exactly are you unsure of? Please remind me of the questions..

well, most of them, except for the calculation part . ummm, do you remember the question asking you to evaluate the hypothesis that one of the sites is better than the other? what did you write?

also, there was a question above it or below it that had 2 marks, don't remember it really, but i have hard time trying to structure my answer.

Edited May 18, 2010 by x___x

[TNT]

What are the correct label for the gene transfer question and for paper 1 what is the universal gene allow us to do, was it gene transfer?

[pomoni]

@ x___x :

I remember I said the hypothesis can be supported but its a little unstable because of the high uncertainties!

I remember there was this graph showing amounts of triglycerides and butyrate (or something like that) in birds at the different sites. Butyrate came from the breaking down of fats as far as I remember. So I said that since there was a higher amount of triglycerides at site 1, means there was a lot of food taken in and stored. Whereas at site 2 the higher amounts of butyrate suggests that the birds were not eating a lot and thus making use of the stored fat for energy supply, and this would lead to the hypothesis that the food at site 1 is of a better quality than site 2. However there were not equal amounts of species used in the experiment (for example I remember there were only 9 American robins) so the results are associated with high uncertainties! But overall the hypothesis would be reasonable.

Does that make any sense to anybody?

And I think you mean the question where it says to give one advantage and one disadvantage of blood sampling instead of weighing?

Edited May 18, 2010 by pomoni

[x___x]

What are the correct label for the gene transfer question and for paper 1 what is the universal gene allow us to do, was it gene transfer?

can someone please answer the first question for us?

and yes, gene transfer is the correct answer.

[x___x]

@ x___x :

I remember I said the hypothesis can be supported but its a little unstable because of the high uncertainties!

I remember there was this graph showing amounts of triglycerides and butyrate (or something like that) in birds at the different sites. Butyrate came from the breaking down of fats as far as I remember. So I said that since there was a higher amount of triglycerides at site 1, means there was a lot of food taken in and stored. Whereas at site 2 the higher amounts of butyrate suggests that the birds were not eating a lot and thus making use of the stored fat for energy supply, and this would lead to the hypothesis that the food at site 1 is of a better quality than site 2. However there were not equal amounts of species used in the experiment (for example I remember there were only 9 American robins) so the results are associated with high uncertainties! But overall the hypothesis would be reasonable.

Does that make any sense to anybody?

And I think you mean the question where it says to give one advantage and one disadvantage of blood sampling instead of weighing?

yes it does, i wish i could have written something near that!

and yeah, could you please tell me what you wrote for the adv. and disadv. question?

[pomoni]

@ x___x :

I remember I said the hypothesis can be supported but its a little unstable because of the high uncertainties!

I remember there was this graph showing amounts of triglycerides and butyrate (or something like that) in birds at the different sites. Butyrate came from the breaking down of fats as far as I remember. So I said that since there was a higher amount of triglycerides at site 1, means there was a lot of food taken in and stored. Whereas at site 2 the higher amounts of butyrate suggests that the birds were not eating a lot and thus making use of the stored fat for energy supply, and this would lead to the hypothesis that the food at site 1 is of a better quality than site 2. However there were not equal amounts of species used in the experiment (for example I remember there were only 9 American robins) so the results are associated with high uncertainties! But overall the hypothesis would be reasonable.

Does that make any sense to anybody?

And I think you mean the question where it says to give one advantage and one disadvantage of blood sampling instead of weighing?

yes it does, i wish i could have written something near that!

and yeah, could you please tell me what you wrote for the adv. and disadv. question?

Why - what did you write for the hypothesis question?

And I'm not sure about the advantages and disadvantages one. I wrote that one advantage of blood sampling is to know the exact nutrients found in the blood and so relations specific to the site can be made. And one disadvantage is that when blood is taken from the bird, so is Oxygen which carries energy. So by taking this energy the feeding behavior of the birds may have been affected leading to uncertainties in results. Do you think that's correct?

What did you write? =)

Edited May 18, 2010 by pomoni