anna123's Content
There have been 31 items by anna123 (Search limited from 16-August 21)
#101443 2008 exam
Posted by
on 01 June 2008 - 06:40 PM
in
Chemistry
#101438 2008 exam
Posted by
on 31 May 2008 - 07:07 PM
in
Chemistry
I hate the SQA!!!! they better lower the grade boundaries I mean it or else I'm gonna protest! 
I wish I can change my uni choices now I chose chemistry!!!! ahhhhh what the hell is that gonna be like!! I hope i get at least a C!! 
I'm still depressed since that paper
#101431 2008 exam
Posted by
on 30 May 2008 - 02:35 PM
in
Chemistry
#101417 Exam
Posted by
on 27 May 2008 - 07:46 PM
in
Biology
). For the essays I did B and I wrote more for mimicry and mutualism than dormancy. I forgot the examples for the mimicry part so I made them up!! I wrote about a butterfly and a snake ( I don't know why but I remembered reading these names somewhere) but i think that they both fit into the one type of mimicry not both :S but still looking at those cut off marks I think I miiiigggghhhhhttttt jussssssttt scrape a B if not then a C is better then nothing! fingers crossed!!
#101413 Exam
Posted by
on 27 May 2008 - 07:24 PM
in
Biology
#101412 Exam
Posted by
on 27 May 2008 - 06:53 PM
in
Biology
#101406 chemistry
Posted by
on 26 May 2008 - 08:20 PM
in
After School
#101404 Pioneer communities
Posted by
on 26 May 2008 - 08:17 PM
in
Biology
As the seeds are light, they can be dispersed by wind. This is efficient as there is a higher chance of survival as the seeds are carried to new habitats to colonise.
Hope this helps!!
#101393 advanced higher biology 2008
Posted by
on 26 May 2008 - 10:32 AM
in
Biology
The answer is C, 25% ( marking scheme)
remember interphase isn't involved in mitosis so for the 2007 paper there are 360 cells in total including interphase. Then divide the total of the other phases except interphase by the total so in this case it's 90/360 x 100 = 25%.
#101386 advanced higher biology 2008
Posted by
on 24 May 2008 - 08:34 PM
in
Biology
interphase is not involved in mitosis ( 2 stages interphase and the mitotic phase) so what you do is you add the number of cells in total in this case there are 500 cells in total including interphase. then you divide the total of the other phases excluding interphase by the total in this case 50/500 x 100 = 10%. This also works for the other 2 questions.
#101378 advanced higher biology 2008
Posted by
on 23 May 2008 - 05:45 PM
in
Biology
#101372 advanced higher biology 2008
Posted by
on 23 May 2008 - 02:13 PM
in
Biology
#101360 advanced higher biology 2008
Posted by
on 22 May 2008 - 01:26 PM
in
Biology
Energy expenditure can also be measured by indirect calorimetry.
The following information was gathered as an individual ran on a treadmill for 20 minutes:
Volume of air breathed out in 20 minutes = 600 litres
Inspired air contained 20% oxygen, while expired air contained 16% oxygen.
4.8 kcals of energy are released for every litre of oxygen used up.
How many kilocalories of energy were expended during the 20 minutes?
#101355 advanced higher biology 2008
Posted by
on 22 May 2008 - 11:52 AM
in
Biology
#101354 Carbon Fixation Cylce
Posted by
on 22 May 2008 - 11:48 AM
in
Biology
Three turns of the cycle, using three molecules of CO2, produces six molecules of G3P. However, only one of the six molecules exits the cycle as an output, while the remaining five enter a complex process that regenerates more RuBP to continue the cycle. Two molecules of G3P, produced by a total of six turns of the cycle, combine to form one molecule of glucose.
http://library.thinkquest.org/C004535/calvin_cycle.html
#101344 Carbon Fixation Cylce
Posted by
on 21 May 2008 - 05:54 PM
in
Biology
Coverage of the Calvin cycle should be done in such a way that the number of carbons is accounted for
throughout the cycle with indications of the position of entry of (a) carbon dioxide which is accepted by
the 5-carbon compound ribulose 1,5-bisphosphate (RuBP) and (b) hydrogen which is accepted by the 3-carbon compound glycerate 3-phosphate (GP). It should be stressed that these reactions, which require ATP and hydrogen provided by the light dependent stage, essentially involve the reduction of carbon dioxide to form carbohydrate.
Candidates are not required to name intermediate chemical compounds except GP (PGA) and RuBP (RuDP).
Mention should be made of the fact that the major biological molecules in plants (eg proteins, fats, carbohydrates, nucleic acids) are derived from the photosynthetic process.
1. A five-carbon sugar molecule called ribulose bisphosphate, or RuBP, is the acceptor that binds CO2 dissolved in the stroma. This process, called CO2 fixation, is catalyzed by the enzyme RuBP carboxylase, forming an unstable six-carbon molecule. This molecule quickly breaks down to give two molecules of the three-carbon 3-phosphoglycerate (3PG), also called phosphoglyceric acid (PGA).
2. The two 3PG molecules are converted into glyceraldehyde 3-phosphate (G3P, a.k.a. phosphoglyceraldehyde, PGAL) molecules, a three-carbon sugar phosphate, by adding a high-energy phosphate group from ATP, then breaking the phosphate bond and adding hydrogen from NADH + H+.
3. Three turns of the cycle, using three molecules of CO2, produces six molecules of G3P. However, only one of the six molecules exits the cycle as an output, while the remaining five enter a complex process that regenerates more RuBP to continue the cycle. Two molecules of G3P, produced by a total of six turns of the cycle, combine to form one molecule of glucose.
#101343 chemistry
Posted by
on 21 May 2008 - 05:34 PM
in
After School
#101340 chemistry
Posted by
on 21 May 2008 - 03:24 PM
in
After School
#101338 chemistry
Posted by
on 21 May 2008 - 03:20 PM
in
After School
#101334 chemistry
Posted by
on 21 May 2008 - 03:00 PM
in
After School
#101330 chemistry
Posted by
on 21 May 2008 - 02:50 PM
in
After School
i hope i get in. So i take it your in 5th year, are you thinking of advanced higher chemistry and biology as well?
#101325 chemistry
Posted by
on 21 May 2008 - 01:59 PM
in
After School
#101323 chemistry
Posted by
on 21 May 2008 - 01:47 PM
in
After School
#101322 Exam 2008 Post Mortem
Posted by
on 21 May 2008 - 01:42 PM
in
Mathematics
#101290 chemistry
Posted by
on 20 May 2008 - 06:02 PM
in
After School
