Not all people have ABO antibodies. Individuals with type A blood have anti-B antibodies, those with type B blood have anti-A antibodies, and those with type AB blood have neither. Type O blood individuals possess both anti-A and anti-B antibodies. However, the presence of these antibodies is specific to the blood type of the individual.
Anti-B
Just looking at ABO/Rh antibodies, you are looking at anti-A present in a B pos person.
ABO blood group
For ABO antibodies, group A has anti-B.
It is the antigens that determine ones blood group.
Testing for Rh antigens and antibodies is done to determine the presence of the Rh factor in the blood, which is a separate system from the ABO blood group system. Rh testing is important for determining compatibility in blood transfusions and during pregnancy. ABO testing, on the other hand, evaluates the presence of A, B, AB, or O antigens on red blood cells to determine blood type.
blood plasma contains no antigens nor antibodies so yes it is universal and can be accepted by anybody.
The antigens of the ABO system are mimicked by bacterial cell walls. So if your body does not actively suppress antibodies to them (because you have them) then antibodies will form over time to the ones you so not have (A or B or both). The rhesus factor (Rh) is not mimicked in nature and so antibodies are not formed in Rh negative people until after an exposure - usually when an Rh negative women carries an Rh positive child. If the person is Rh positive then antibodies will not form no matter what.
Individuals with type A blood produce anti-B antibodies and individuals with type B produce anti A. There are many sub groups of blood antibodies such as D (Rh) but we usually only refer to the ABO systems.
if O- mother consives A+ OR B- baby any foetal A or B TYPE RBC ENTERING THE MOTHERS blood cells are quickly distroyed by her anti-A or anti-B antibodies before she can form -Rh antibodies
If your ABO blood type is AB, you could potentially give blood to individuals with blood types A, B, AB, and O, as long as there are no other significant blood type incompatibilities. The AB blood type is known as the universal plasma donor because it lacks ABO antibodies in the plasma.
In the ABO blood group system, a person's immune system naturally creates antibodies to the antigens that it lacks. Group A people have the A antigen, so they will make Anti-B. Group B people have the B antigen, so they will make Anti-A. Group O people do not have A or B antigens, so they make both Anti A and Anti B. Group AB people have both A and B antigens. They do not have antibodies in this blood group system. So, the short answer to your question: B and O people will both have Anti-A in their blood.