Ventricular fibrillation is one type of arrhythmia that can be deadly. It occurs when the heart beats with rapid, erratic electrical impulses. This causes pumping chambers in your heart (the ventricles) to quiver uselessly instead of pumping blood. Without an effective heartbeat, blood pressure plummets, cutting off blood supply to your vital organs.
In the ABO system, (and Rhesus D system) all blood belongs to one of four major groups: A+/â, B+/â, AB+/â, or O+/â. The presence (+) or absence (â) of the RhD (Rhesus D) antigen is indicated by the plus or minus following the ABO type. But there are more than two hundred minor blood groups that can complicate blood transfusions. These are known as rare blood types.
2.There are four major blood groups, and they are also subject to the Rh factor, so in reality there are 8 human blood types. The types are A+, A-, B+, B-, AB+, AB-, O+ and O-. Blood types are inherited by the person inheriting one allele for a given blood group from one parent and another from the other parent.