Edexcel igcse biology may 2012 exam discussion

I totally agree with this. You also have the people from overseas taking in January as there school years are different, and I bet they do better than us haha...Personally, I didn't find this the hardest paper, however It was probably one of the most vague/awkwardly questioned one, and for a lot of questions I have heard a lot answers...so hopefully I think it will be around the 144-146 region.

The grade boundary as a SET rule is always lower in resits, atleast thats what we got told. Many people found this paper easy actually but it was awkward, it doesn't mean grade boundaries will shoot down.

The grade boundary as a SET rule is always lower in resits, atleast thats what we got told. Many people found this paper easy actually but it was awkward, it doesn't mean grade boundaries will shoot down.

Just a theory : It is fair to say people that are resitting an exam have done more revision than they would have done revising for the real thing. Thus they will be more prepared as a collective group than the initial group of candidates on account of time spent on revision. Therefore surely they would do better in a paper that is of the same difficulty as the one they sat in the summer thus raising the grade boundary instead of lowering it. Of course this is based on generalisation but I think it is justifiable to assume people doing a resit want to do better and thus do more revision.

Well I don't think you can really make such a set rule, seeing as the first paper In the 2009 specification was it not taken last june? Given to this only two exams have been taken! With only a 1.6% difference in each..

Hey guys I'm new here so go easy on me!

For the question that asked you to define a transgenic organism, I put: an organism which has received material from an organism of a different species. Now I'm worrying because for the life of me I'm unsure if I wrote genetic material or not.
If not, would I still get the mark?

I thought I did okay in the first paper, then thought I did better in the second but looking at the answers you guys gave I'm not so sure now.
I was predicted A* but got 3% under in the mocks. If the grade boundary for an A* is 80% I might just wing it but if it's anything higher I'm not so sure I will.

Any ideas what type of boundaries we're gonna be looking at?


This was posted from The Student Room's iPhone/iPad App

Hey guys I'm new here so go easy on me!

For the question that asked you to define a transgenic organism, I put: an organism which has received material from an organism of a different species. Now I'm worrying because for the life of me I'm unsure if I wrote genetic material or not.
If not, would I still get the mark?

I thought I did okay in the first paper, then thought I did better in the second but looking at the answers you guys gave I'm not so sure now.
I was predicted A* but got 3% under in the mocks. If the grade boundary for an A* is 80% I might just wing it but if it's anything higher I'm not so sure I will.

Any ideas what type of boundaries we're gonna be looking at?


This was posted from The Student Room's iPhone/iPad App

1. Being outside means increased exposure to the sun. This means that vitamin D levels are higher and thus going outside more often decreases the chance of Rickets.
2. Adults are less prone to Rickets as their bones have already finished developing whereas the bones of a child develop until even after puberty. Therefore, given that Rickets affects development of bones and thus poses more of a risk to children than it does to adults.
3. Minerals, Carbohydrates, Fats.
4. These foods are high in carbohydrates. These carbohydrates would be stored as fats and used as energy stores for later use in respiration. If however the child does not exercise then he will never use up these stores of fat and will thus experience an unhealthy gain in mass and likely diabetes.
5. Too much fat could lead to atherosclerosis whereby plaques of cholesterol develop within the lumen of an artery and thus disrupt blood flow. This can cause arteries to rupture and is particularly dangerous if it occurs in the coronary vessels. The plaques would decrease blood flow to parts of the heart tissue thus starving it off oxygen and causing it to die. This would then cause a heart attack.
6. You would set up a simple calorimeter using the following apparatus : Bunsen burner, Needle, tripod, beaker of water, thermometer. You would set fire to the piece of food and place it underneath the beaker of water, having measured the initial volume and temperature of the water, until all of the food has been burnt off. You would then calculate the energy released by the food by calculating the change in temperature and the change in volume of the water over the course of the experiment.
7. FILL IN THE BLANK QUESTION – nucleic acid, RNA, immune, white, antibodies, vaccination.
8. 15 days
9. 15th day (NOT 14th as would be expected)
10. Hormone A = Oestrogen
11. Hormone B = Progesterone (or other way around can’t remember exact order)
12. Breasts, Pubic hair
13. Restriction endonucleases
14. DNA ligase
15. A plasmid
16. A transgenic organism is one that possesses one or more genes from an organism of another species.
17. More genetically identical sheep means that more sheep can produce the Human protein which means that more of it can be produced. More than one sheep with gene means that if something happens to the parent, the human protein can still be produced.
18. Student 8
19. They are reliable because, in essence, the experiment has been repeated 10 times and is thus reliable while the results of the individual students might not be.
20. AHEC
21. Nitrification refers to the process whereby ammonia in the soil is turned into nitrites and then nitrates. This means that nitrification increases the uptake of nitrates from the soil by plants because there are more nitrates in the soil.
22. Legumes have a mutualistic relationship with nitrogen-fixing bacteria. These nitrogen-fixing bacteria turn nitrogen into ammonia which they provide to the clover / legume. When the legume decomposes it releases nitrates into the soil which leads to more nitrate being taken up by the cereal crop. The cereal crop needs nitrates in order to grow properly (for DNA) and for the production of chlorophyll for photosynthesis. Thus by planting legumes in the soil before planting the cereal crops, the farmer is increasing the yield of the crop.
23. Energy is lost between trophic levels due to cellular metabolism such as respiration and excretion by the organism.
24. Soot causes Emphysema whereby the alveoli are damaged and fuse together thus decreasing their surface area. This means that the rate of gas exchange is lower. Smoke stimulates the goblet cells to produce mucus while at the same time killing the ciliated epithelial cells which results in a chesty cough and a decreased amount of air travelling through the trachea into the lungs. Carbon monoxide in smoke bonds with haemoglobin to form carboxyhaemoglobin which leads to a decrease in the volume of gas exchanged at the alveoli.

Thank you soo much! How did you find the paper?

That bloody legume question...

Literally had no idea what to right, so just made it up...

Anyone know when a question paper will be up

No one's centre give them out :/

has anyone tried?
i keep going on and on about this but it would help everybody so much if we could get the papers like maths-so we could calculate marks and grade boundaries.

Hey guys I'm new here so go easy on me!

For the question that asked you to define a transgenic organism, I put: an organism which has received material from an organism of a different species. Now I'm worrying because for the life of me I'm unsure if I wrote genetic material or not.
If not, would I still get the mark?

I thought I did okay in the first paper, then thought I did better in the second but looking at the answers you guys gave I'm not so sure now.
I was predicted A* but got 3% under in the mocks. If the grade boundary for an A* is 80% I might just wing it but if it's anything higher I'm not so sure I will.

Any ideas what type of boundaries we're gonna be looking at?


This was posted from The Student Room's iPhone/iPad App

That's the thing! Some centres do give it out, obviously no one who does biology here goes to such a centre.