Professional and Linguistic Assessments Board (PLAB) Practice Exam

Disable ads (and more) with a membership for a one time $2.99 payment

Enhance your chances of passing the PLAB Exam. Study with our practice quizzes that feature multiple choice questions, comprehensive hints, and explanations. Prepare with confidence!

Each practice test/flash card set has 50 randomly selected questions from a bank of over 500. You'll get a new set of questions each time!

Practice this question and more.

What is considered the universal blood type?

AB+
O-
A+
B-

The correct answer is: O-

The universal blood type is O-negative (O-). This designation arises from the lack of A and B antigens on the red blood cells of individuals with this blood type. Furthermore, O-negative blood lacks the Rh factor, meaning it can be safely given to patients of any blood type without causing an adverse reaction due to blood type incompatibility. This characteristic makes O-negative blood especially valuable in emergency situations where there may not be enough time to determine a patient's blood type. In contrast, other blood types, such as AB-positive or A-positive, contain specific antigens that could potentially lead to severe allergic reactions if transfused into someone who does not have those antigens. The absence of antigens in O-negative blood is what solidifies its status as the universal donor type.