Edexcel A2 Biology Unit 4 Revision for 15 June 2012 Examination!

[MKh]

Hellos,

So who else is sitting for this exam in this june session? Well, I am. Actually, it's a re-sit.

I have created this thread to discuss about the Edexcel A2 Biology Unit 4 exam which will be held on the 15th of June 2012, what might come up, solve doubts and so on.

So to start with, how far have you guys gone in terms of revision? I also want to know if anyone has got any useful 'Practice Questions' for the Core Practicals in the unit 4 spec.

Also what do we have to know for the following specification point in topic 6 of unit 4 of the specification:
13 Explain the roles of antigens and antibodies in the body’s immune response including the involvement of plasma cells, macrophages and antigen-presenting cells.

Good Luck and feel free to discuss.

P.S. I am really sorry if this is in the wrong section. Admins/mods : move it to where it seems appropriate.

[sweetsh]

It's alright, an admin/mod will move it if appropriate. I guess it might be better to be in  "Subject Doubts > Sciences"

[Most UniQue™]

Just to let you know , the exam paper discussion will take place in another thread which will be created soon so this topic will soon be locked.

[sweetsh]

Just to let you know , the exam paper discussion will take place in another thread which will be created soon so this topic will soon be locked.

He didn't create the thread to discuss the exam that will conduct in June, it's for revision and questions and so

[Most UniQue™]

The topic says "Edexcel A2 Biology Unit 4, 15 June 2012 Examination Discussion here!" and its a "she"

[sweetsh]

The topic says "Edexcel A2 Biology Unit 4, 15 June 2012 Examination Discussion here!" and its a "she"

I can read. I found it irrelevant as well, the title doesn't relate to the post

[Malak]

The title can be changed and the thread moved to subject doubts since it is more like revision dicussion.

[MKh]

The topic says "Edexcel A2 Biology Unit 4, 15 June 2012 Examination Discussion here!"

So sorry, should have written 'Revision Discussion' or something of the sort instead.

The title can be changed and the thread moved to subject doubts since it is more like revision dicussion.

Ohkay, thanks for moving it then.

[MKh]

Just to let you know , the exam paper discussion will take place in another thread which will be created soon so this topic will soon be locked.

You can, if you want to, lock this thread. But I want to have a specific thread to discuss about a specific exam because I believe it will be very helpful. Last year, when I was taking the biology unit 5 exam, the unit 5 article discussion thread proved so helpful to me and so is a similar thread being helpful to many this year. The unit 4 exam is taken by many candidates so I thought it was a good idea. By the way, will you create a similar thread for the discussion of this particular exam or for Edexcel exams as a whole?

[Most UniQue™]

Since its a revision thread , it wont be locked.

Edexcel exam as a whole. It takes place over here

[MKh]

I have a doubt. Please help me if anyone can.

In topic 6 of unit 4 bio, what do we have to know for the following specification point:
13. Explain the roles of antigens and antibodies in the body’s immune response including the involvement of plasma cells, macrophages and antigen-presenting cells.

And does anyone have any specfc questions on the Core Practicals in unit 4?

Thanks.

[Romeesa-Chan]

13. Explain the roles of antigens and antibodies in the body’s immune response including the involvement of plasma cells, macrophages and antigen-presenting cells.

Any substance that raises an alarm in the body, causing the immune system to react to and attack it is called an antigen. The main function of antigen-presenting cells (APCs) is to help lymphocytes recognize antigens on foreign cells (including cancer cells). Antigen-presenting cells include monocytes, macrophages, and dendritic cells.

Plasma cells release antibodies that bind (attach) only to that antigen. The antibodies then help kill any cells that have the antigen. The antibodies may destroy them directly or they may serve as a marker for other immune system cells, such as T cells, to destroy them.

Macrophages, capable of surrounding and "eating" unwanted cells. They then present antigens from the devoured cells on their outer surface, so that lymphocytes can recognize the foreign antigens if they are found in the body later on.



[source: http://www.cancer.org/Treatment/TreatmentsandSideEffects/TreatmentTypes/Immunotherapy/immunotherapy-immune-system]

[MKh]

Any substance that raises an alarm in the body, causing the immune system to react to and attack it is called an antigen. The main function of antigen-presenting cells (APCs) is to help lymphocytes recognize antigens on foreign cells (including cancer cells). Antigen-presenting cells include monocytes, macrophages, and dendritic cells.

Plasma cells release antibodies that bind (attach) only to that antigen. The antibodies then help kill any cells that have the antigen. The antibodies may destroy them directly or they may serve as a marker for other immune system cells, such as T cells, to destroy them.

Macrophages, capable of surrounding and "eating" unwanted cells. They then present antigens from the devoured cells on their outer surface, so that lymphocytes can recognize the foreign antigens if they are found in the body later on.



Thanks.

[source: http://www.cancer.org/Treatment/TreatmentsandSideEffects/TreatmentTypes/Immunotherapy/immunotherapy-immune-system]