~Lc~

We used extracts from "A History of World Societies" by John P McKay, Bennett D Hill and Roger B Beck on the Italian unification and "Germany 1848-1914" by Bob Whitfield on the German unification if your school has any of them or you can find them elsewhere. If you have any specific questions I'll be happy to help you.

First off, what subject is your extended essay in? Biology? Psychology? The appropriateness depends on the subject you are writing in. Symptoms and hazards are not factors that cause anorexia, however, they are more byproducts of anorexia (unless I have misread).

Alrighty.
Thylakoids are organelles/compartments found inside the chloroplast as you know. Thylakoids are membrane bound, in other words they have a lumen(containing everything needed for the light independent reaction) that is surrounded by the membrane( containing the proteins of the chain). Try to think of them as a discs:



When they're stacked together they become connected with each other, forming a granum and with other stacks(grana). Here's a picture of 3 thylakoids connected:




Like I said previously, the membrane contains the proteins forming the electron transport chain. Within this chain there are 2 'units', each containing hundreds of the green chlorophyll molecules (the main photosynthesis pigment). They are the units that capture the light and they're called photosystem. For SL, that's the maximum you have to know about photosystems.
As for the P1 and P2: they are found within the chain, basically 2 different types of units.

All you have to know is that light is captured by the P2 first then P1.

Hello people!

I have seen Biology, Chemistry and Physics help threads; I figured I would create one for Mathematics too.

I'm willing to help any Mathematics student with their problems or doubts. I am sure there would also be some other helpers, so if you have any Math question just post here unless they are questions regarding IA tasks. Questions regarding IA tasks must be posted in the correct IA threads and not here. Questions from textbooks, worksheets or even past year papers may be asked here no matter whether they are for Math HL, SL or even Studies.

Please also include which Math level you are taking so the solution and explanation would be suitable with the extent that you need to know because Math HL, SL and Studies are very different.

Don't be afraid to ask! Enjoy!

Think about what your trying to prove, and put that into a research question/Thesis.

What about their relationship is unconventional or how did it form? What about society (or what did society do) to help make their relationship form, or make it unconventional?

These aren't thesis at all, just questions to help you out.

Daedalus, on Jan 04, 2011 - 20:37, said:

Daedalus, on Jan 04, 2011 - 20:37, said:

*C.3.2: Glycolysis*

Takes place in the cytoplasm

1)Phosphorylation:
Glucose (6C) -----------(2 ATP---->2 ADP+Pi)------------------------------->Hexose Bisphosphate
Basically, you have the sugar you start with and it is turned into another form by adding 2 phosphates. Why? Because that reduces the energy of activation for the next reaction.

2) Lysis:
Hexose Bisphosphate -----------------------------------------------------------> 2 Triosphosphate.
Lysis obviously means breaking down. So we have a 6 carbon sugar that has been split into two others with 3 carbons and PO4 each.

3) Oxidation:
It's loss of electron or Hydrogen and gain of oxygen.
2 Triosphosphate -------------(NAD⁺----->NADH+H⁺)----------------------------------->2 Pyruvate (3C)
The NAD⁺ took 2H from the 2 Triosphosphate (from the PO₄ specifically)

4)ATP Formation:
This happens with the previous step.
4ADP+Pi ------------------------->4ATP.

So, glycolysis used 2 ATP and produce 4.

If you were asked about the yield:
2 ATP, 2 NADH+H⁺, 2 Pyruvate.

*C.3.4-Link Reaction, Kreb's Cycle and Transport Chain*

Link Reaction:

Pyruvate (3C)----(NAD⁺-->NADH+H⁺)-------------(CO₂ released)----------------------------------> Acetyl Coenzyme A (2C)

This is just turning 3C to 2C by taking away 2H (oxidation) and 1CO₂ (Decarboxylation). Therefore, this step is called oxidative decarboxylation.


Kreb's Cycle: (Put the diagram in front of you before you read the next)

• After the link reaction, you have acytelcoA, a 2 Carbon molecule with the coA enzyme.
  
• The Cycle starts with a 4carbon.
  
• The 2carbon is added to it so: 2+4=6 we get a 6 carbon molecule.
  
• The 6 carbon is changed into 5 carbon. Therefore, we must reduce the carbon number by removing CO₂, so CO₂ is lost. Everytime a CO₂ is lost, a H₂ is lost as well. So you have the NAD⁺ + H₂----> NADH⁺ + H⁺.
  
• The 5 carbon is changed into 4carbon by the exact same process, CO₂ and NADH⁺ + H⁺ formed.
  
• The 4 carbon formed isnt the same as the one we started with, so to get it back to the first one, we remove 2H_2. One is taken by the NAD⁺ and the other by FAD.
  
• ATP is formed as well in this process.
  
• So to sum up the krebs cylce produces the following: 1 ATP, 1 FADH₂, 3NADH⁺ + H⁺, 2CO₂

*C.3.5--Oxidative phosphorylation.*

Oxidative phosphorylation.

Takes place on the electron carrier chain located on cristae or the folds of the mitochondria.
Okay I am going go try and explain this the best I can:

NAD+H⁺ we had earlier is going to come along and give an electron to a protein in the chain, and the electron will go from one protein to another Every time that happens, 2H go from the matrix to the inter-membrane space.
You will have that space filled with H⁺ (protons). At the end of the chain, there's an enzyme called ATP synthase, the H⁺s will be pumped back to the matrix, with every H⁺, you have an ATP made.

The movement of H⁺ down the concentration gradient is called chemiosmosis.

Now, the O₂ we breath in is only used now:
the electrons that have been passed along from one protein to another are released back to the matrix and taken by the the H⁺. 1 electron + 1 proton will give you a hydrogen. 2 of those are combined with the O₂, which will give you water.

*C.3.6-Structure and Function of Mitochondria*

Mitochondria:
1)The cristae give the largest possible surface area for the chemiosmosis to take place, therefore more ATP formation.
2) Inter-membrane space is very small, so it's filled easily, which will form the gradient quickly.
3)The matrix has all the enzymes used in the krebs cycle.

2.In other words, for your World Lit, IOC, Science Lab Reports, and so on, your teacher sends out a "representative" sample

These components are all externally assessed regardless of the number of students in the class.

• Extended essay
  
• Theory of knowledge essay
  
• Language A1 world literature
  
• Language A1 school supported self-taught oral examination audio recording
  
• Language A2 written task
  
• Music: Musical investigation
  
• Theatre practical performance proposals and research investigations

The rest are called internal assessments (these are marked by your teacher and examiners moderate their marks) such as science lab reports, mathematics portfolios etc.

3.The size of this sample depends on the number of students in your class (I think - this is the one point that needs confirming)

This is indeed true. However, to be more precise:

Students in a class:

• <= 5:  all works
  
• 6-20: 5 candidates' works
  
• 21-40: 8 candidates' works
  
• >=41: 10 candidates' works

Just throwing this out there, because I see a lot of questions and a lot of wishy-washy answers about this...

• Your score in certain subjects is made up of components that are internally assessed and externally moderated
  
• Addition: some components, like your World Literature essay(s), ToK essay, and of course Extended Essay, are not moderated but assessed (i.e. all sent off) [thanks for lynyrd and imopotato for pointing out that the WL is not moderated]
  
• For others, like your IOC, Mathematics portfolios, Science Lab Reports, Economics Portfolio, (and so on), your teacher sends out a "representative" sample
  
• The size of this sample depends on the number of students in your class (imopotato cites the following; students in class : number of students' samples sent off: 5 or less : all | 6-20 : 5 | 21-41 : 8 | more than 41 : 10 |. This sounds reasonable to me.
  
• The sample consists of: the best score(s); the worst score(s); and the score(s) closest to the three quartiles (25%; 50%; 75%)... in other words a sample spread fairly accross the board
  
• The IB responds with a moderating curve, to adjust your teacher's scoring to the IB-school-wide standard This mechanism is not entirely easy to understand, but all you need to know is
  
• Sometimes all of the samples have been marked up, leading to a higher mark for all pieces handed in in the class
  
• Sometimes they are all marked down, leading to lower grades for everybody
  
• Sometimes (often, apparently) the top scores drop 1-2 marks, and the bottom ones gain 1-2 marks (imagine a sinuous sort of curve)

I can't really vouch for the technical accuracy of these statements, because my teachers gave them to me (semi-confidentially), but you can be almost certain that they are correct.

In terms of the implications ... the main one I guess is make sure you don't beg your teacher for marks, because you are putting an entire class' grades into jeopardy. An interesting side note is you can "cheat" in a sense and ensure your pieces of work aren't sent off for moderation, if you have a very obliging teacher. But I wouldn't recommend this; firstly because, as well all know from ToK, induction is not a reliable process (i.e. this could change for next year), and secondly, a teacher that obliging probably will cause the entire grade to be moderated down anyways.

One thing you can do is contact your IB Coordinator if you think your teacher is grading you poorly. Because if he is, and you're still doing top-notch work, your own score might suffer.

Anything to add or subtract from this is appreciated.

Update on external assessment. Turns out your IB Coordinator sends materials directly to the Examiners as told by IBO, who mark a large stack of papers and send a certain sample (following the same guidelines as above) to be remarked by another Examiner. It goes up in terms of seniority, in some way or another, so some papers end up being marked three times (the honour!) and some end up on the Chief Examiner's desk. The mechanism isn't entirely clear either but it seems to be quite close to a foolproof system, and you can also ask for a remark.

Just thought I would chime in (because I'm procrastinating again!).

First of all, I want to stress that Elsa (~Lc~) and Hien (Ruan Chun Xian) are the only reason this site really became a reality. It was first created after I spent hours and hours and more hours creating various notes for subjects in order to help students in my class. My year at school were the first to sit the IB so most of the teachers were still a bit dodgy when it came to the details of IB assessments, etc. I took it upon myself to do the research and eventually built up a database of various things (curriculum, notes, samples, etc). I've always felt that people should have access to these things. Initially we were just giving out things for free, but like most things, it costs money to provide certain services. We have almost 5GB of files here and the site takes up quite a lot of bandwidth. In fact, the growth recently means that I will probably have to expand a bit (which I've put some money aside for).

There are still some big ideas I have about further developing the site, but I first have to finish my next set of exams! Then I can spend some more time here and add some new features. If you have any queries or ideas, please let me know!

~Julie~, on Jan 14, 2011 - 03:54, said:

Yes. You don't neccesarliy have to report any posts that have capslock, wierd fonts, etc. we can deal with that although it would be nice to notify us. Repoting should mainly be used for seeing a post with content such as giving away answers for a portfolio, obvious spam posts, rude and offsensive posts, blatant discrimination, etc. You can see more information here: http://www.ibsurviva...tion=boardrules

I wrote my first biology lab report before a week, and i am doing the second one and the deadline is after two days. I do not have much experience, but my last Lab was about 2000 word. Including diagrams it was about 10 pages. I used to draw some figures, with pencil and my techer told that i can drw them by pencil. The length is something dependant on the lab, and the data you collect. You should go through criteria, if you fulfill it by 100 words (which is not a true) its okay. 10 pages for conclusion is to much.

I wrote a comment 5 days, in which i wrote:
Finished from the first lab report, with word count =2000 words. Is this too much?

And i got two totally different comments:

Quote

So it is something that depend on you, but you should do what the criteria requested.

This is  what is requested to write in your lab report:

i) design:
- Specific Title
- Introduction (Peferable if design)
-Aim and Varibales  (2marks)
- Hypotheses (Justified)
-Methodology: i) Materials ii) Procedure (It should contain how you will controll variables and how you will collect data) (4marks)

ii) Data collection and processing:
- Data collection (2 marks) (of the dependant variables)
-Data processing and analysis (2 marks)
-Presenting (Graphs and tables)

iii) conclusion and evalution;
-conclusion  (2marks)
-Evalution ( 1) Sources of error: i)Systemetic   ii) Random
                      2) Ways of improvement
*References (Must if design)
So your lab should be complete and word numbers are not important.

This was give by my chemistry teacher who i trust, (He is an IB examiner)
More information can be got from drake comment in http://www.ibsurviva...0806#entry90806

So, just incase this isn't clear:

Today is.....You can discuss.....

•October-30
School based syllabus SL Paper 1 [13:00]

•November-3
All Language B SL/HL paper 1&2 [13:00]
Language Ab initio SL Paper 1 &2[13:00]
(NOT: English, French & Spanish B and French and Spanish ab initio)
Biology SL Papers 1&2 [18:00]
Biology HL Papers 1&2 [18:00]
ESS SL Paper 1 [18:00]

•November-4
Biology HL Paper 3 [13:00]
Biology SL Paper 3 [13:00]
Environmental Systems and societies [13:00]
Spanish A1 SL/HL Paper 1 [18:00]
Spanish A2 SL/HL Paper 1 [18:00]

•November-5
ALL SPANISH PAPERS [13:00]
Math HL Paper 1 [18:00]
Math SL Paper 1 [18:00]
Math Studies SL Paper 1 [18:00]

•November-6
Math HL Paper 2 [13:00]
Math SL Paper 2 [13:00]
Math Studies SL paper 2 [13:00]
Language A1 HL/SL Paper 1 [18:00]
Language A2 HL/SL Paper 1 [18:00]
(NOT English, French and Spanish)

•November-9
Language A1 HL/SL Paper 2 [13:00]
Language A2 HL/SL Paper 2 [13:00]
(NOT English, French and Spanish)
Physics HL/SL Papers 1&2 [18:00]
Sport, exercise and health science SL Papers 1&2 [18:00]

•November-10
Physics HL/SL Paper 3 [13:00]
Sport, exercise and health science SL Paper 3 [13:00]
English A1 SL/HL Paper 1 [18:00]
Text and performance SL Paper 1 [18:00]

•November-11
ALL ENGLISH PAPERS [13:00]
Economics HL Papers 1&2 [18:00]
Economics SL Paper 1 [18:00]

•November-12
Economics SL Paper 2 [13:00]
Economics HL Paper 3 [13:00]
Chemistry HL/SL Papers 1&2 [18:00]
Design technology HL/SL Papers 1&2 [18:00]

•November-13
Chemistry HL/SL Paper 3 [13:00]
Design Technology HL/SL Paper 3 [13:00]
History HL/SL Papers 1&2 [18:00]

•November-16
History HL Paper 3 [13:00]
Math HL Paper 3 [18:00]
Classical languages HL/SL Paper 1 [18:00]
ITGS HL/SL Paper 1 [18:00]

•November-17
Classical languages HL/SL Paper 2 [13:00]
ITGS HL Papers 2&3 [13:00]
ITGS SL Paper 2 [13:00]
Music HL/SL Paper 1 [13:00]
Geography HL/SL Paper 1 [18:00]
Social & cultural anthropology HL/SL Paper 1 [18:00]
Computer science HL/SL Paper 1 [18:00]
Psychology HL/SL Paper 1 [18:00]

•November-18
Geography HL/SL Paper 2 [13:00]
Social and cultural anthropology HL Papers 2&3 [13:00]
Social and cultural anthropology SL Paper 2 [13:00]
Computer science HL/SL Paper 2 [13:00]
Psychology HL Papers 2&3 [13:00]
Psychology SL Paper 2 [13:00]
French A1 HL/SL Paper 1 [18:00]
French A2 HL/SL Paper 1 [18:00]

•November-19
ALL FRENCH PAPERS [13:00]
Business& management HL/SL Paper 1 [18:00]
Philosophy HL/SL Paper 1 [18:00]

•November-20
Business & management HL/SL Paper 2 [13:00]
Philosophy HL Papers 2&3  [18:00]
Philosophy SL Paper 2 [18:00]

Please make sure you stick to these dates when discussing exam papers.

I wish you all the best of luck in your exams.

Is this literally just to practice how to research things?

Generally with research (and any essay) it's easiest to structure it around your argument. This should involve
1) Providing evidence for and explaining the origins of your argument
2) Outlining your main points
3) Concluding

"Why did middle aged, middle-class, white males in California during the last decade, commit adultery?"

For this kind of essay you want to 'set the scene' of your essay. So you start with the evidence that middle-aged middle-class white males committed adultery. Outline what adultery is and how you're going to define it. When you mention your data also discuss its strengths and weaknesses (for instance with stuff like adultery the most obvious problem is poor reporting!). Reference everything thoroughly.

Then move on to make your points, one by one and with references/evidence for everything you say, as to the various reasons why they might have committed adultery. Remember to always discuss the relative merits of whatever evidence you're using.

Finally, conclude with whatever you find out and try to make it a balanced summary of both the merits and flaws of what you've found out.

Those are the sorts of things which are important -- separate your paper into sub-headings to make it nice and clear and be extremely thorough in finding sources for ALL the assertions you make.

That's ideally the kind of approach to take to an Extended Essay too


This is a bit of a weird question

A quick Google Scholar search returned this study where he compares 4 different mnemonic techniques.

Aren't you supposed to change something though for the HL study?  For example, you keep experimental paradigm but you change the IV and see the effects...That's what I remember at least.

Nevermind, just checked.  For the new syllabus you can replicate or modify an original experiment.