Blood Drug Testing

How does testing for blood types work?

i saw someone doing a test and they took a bit of blood from the persons finger and placed 3 drops on a slide and on each drop she added 3 chemicals and then the blood type was determined.. i didnt think it was that simple?

Public Comments

1. well, basically our blood grouping is determined by certain antigens and antibodies in our blood. there are antigen A, antigen B, antibody A and antibody B. a person with A blood group, he has antigen A and antibody B and vice versa with person with B blood group. AB blood group has both antigens but none of the antibodies while O blood group has none of the antigens but both of the antibodies. the basic here is that antibody will attack the antigen of corresponding name. example, antibody A will attack antigen A and antibody B will attack antigen B. this attack will cause the blood to agglutinate. thats why our blood do not have the same antigen and antibody. 2 of the chemicals that you mentioned must be antiserum A( contains antibody A) and antiserum B. then the antiserum is mixed with blood, the presence of agglutination of the blood will tell us the blood group. if the blood agglutinates on antiserum A only, this means the blood has antigen A, thus is blood group A if the blood agglutinates on antiserum B only, this indicates the blood has antigen B, thus is blood group B if the blood agglutinatess on both antiserum, this means it has both antigens, thus blood group AB if the blood do not agglutinates on both, is blood group O about the third chemical that is used, i think it is antiserum Rhesus. besides categorising our blood into ABO blood group, there is also another grouping called Rhesus factor. its either we are Rh+ or Rh-.. Rh+ means the antigen Rh is present in the blood..so, if the blood agglutinates, its Rh+.. the reason behind Rhesus testing is that if the mother will reject the fetus if the mother is Rh- while the fetus is Rh+.. your right..its not that simple..