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Blood types

  1. Mar 6, 2006 #1
    Well Im wondering.

    I know all the basics of blood types. How you can be AA-AO OO, AB, BB-BO
    and ive done the thing to find out which one I am. and Im AA or AO

    But Ive heard of A+ or A-

    so what's with the + or -
    whats the difference.
    and how is it determined if your + or -
  2. jcsd
  3. Mar 6, 2006 #2
    Last edited by a moderator: Apr 22, 2017
  4. Mar 8, 2006 #3
    Where did the system of A, B, O and such come from? What blood type is the most rare? The article made sense, but it didn't describe how you find out if you are + or -. I'd assume you would take a blood test obviously, but what do they do to the blood to determine what it is?

  5. Mar 8, 2006 #4
    Why can all bodies accept O negative blood? Can a person with O negative blood accept another blood type?

  6. Mar 8, 2006 #5


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    All bodies can accept O negative blood because O has no antigens on the cell membrane.
  7. Mar 8, 2006 #6
    There is nothing special about X -. It is the positivs that has th Rh- factor.

    However, people with 0 negative can only accept blood from donors with 0 negative.
  8. Mar 8, 2006 #7

    AB is the rarest.
    OO least rare

    and there is an antigen for each letter which coagulates(clumps up) the blood if mixed poorly.

    the article explains the +-

    So as it stands. the higher on the rare scale. the better off in ways of what types of blood you can accept. Though from my understanding. If your AB and get an infusion of BB you'll feel groggy and tired.

    ya im still wondering about this to. however i imagine that they simply test the blood for that protein.
  9. Mar 8, 2006 #8
    Because of the Rh- factors and the antigens. (Could someone remind me what an antigen is please...I can't remember.)

  10. Mar 8, 2006 #9
  11. Mar 8, 2006 #10
    Ah thanks so much.

  12. Mar 8, 2006 #11
    munky99999, you may be incorrect.

    It all depends on when it happens. The first time, your body hasn't developed the antibodies against the foreign blood. Then it is correct. You will feel groggy and sick and worse. But you will not die. Not the first time atleast.

    The second time, your body will have ready antibodies for the blood. When you recieve the blood the antibodies will attack the bloodcells and kill them by making them clump together.

    The blood cannot pass trough and you die.
  13. Mar 8, 2006 #12
    Wait...is that if you receive the wrong blood type in a transfusion? What if you have already had a transfusion, but you're in the emergency room and they have to transfuse you but they don't know what blood type you are so they use O negative? Will it kill you?

  14. Mar 8, 2006 #13
    Well things like this can happen and its pretty easy to get past things like this. Usually the person comes with a record which would say what type. but say this is completely nobody

    You can take a little of the person's blood, and take what u want to infuse into him. mix it outside the body and taadddaaa. you can tell before hand if it will coagulate.

    But the sure bet way to go is O- as it wont coagulate.

    As for Mattara i dunno. I havent read that before.
  15. Mar 8, 2006 #14
    Oh Mattara? Mattara where are you? :wink:

    That wasn't something I read. I heard about it though. I was just wondering. Yeah mixing outside the body for coagulation is a good idea. How do you go that without opening the bag and exposing the blood to air bourn infections?

  16. Mar 8, 2006 #15
    I don't understand what this is meant as...
  17. Mar 8, 2006 #16
    Nothing I was just paging you to see if you were still reading through the thread. Thats all. Sorry.

  18. Mar 8, 2006 #17
    Did you read my last question?

  19. Mar 8, 2006 #18
    to sum up:

    This wont kill you:

    A can give to A, AB
    B can give to B, AB
    O can give to A, B, AB, O

    Rh + can give to Rh+
    Rh - can give to Rh + and Rh-

    misskitty, What was your last question?

    munky99999, my source is Heinemann Advanced Science Biology 2nd edition by Ann Fullick.
    Last edited: Mar 8, 2006
  20. Mar 8, 2006 #19
  21. Mar 8, 2006 #20
    Most of the time, the hospital will have your blood type on record. At least if you are in any industrial country. If they don't have it, they can perform test with your blood and test it for antigens (not using any other blood).

    If you are in a "primitive" hospital, they could perform that perticular method as described by munky99999.
    Last edited: Mar 8, 2006
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