Speaker 1: Welcome to brain Stop from house stuff works dot com
Speaker 1: where smart Happens. Hi, I'm Marshall Brain with today's question.
Speaker 1: Are all blood types needed for donation? So let's start
Speaker 1: at the beginning. A blood group or a blood type
Speaker 1: is based on the presence or absence of two different
Speaker 1: proteins called A and B on the surface of red
Speaker 1: blood cells. Because there are two proteins involved, there are
Speaker 1: four possible combinations or blood types known as A bio groups.
Speaker 1: There's type A blood where only the A protein is present,
Speaker 1: There's type B blood where only the B protein is present.
Speaker 1: There's type A B blood where both proteins are present,
Speaker 1: and then there's type O blood where neither protein is present.
Speaker 1: And this is about the population. In addition to the
Speaker 1: A and B proteins, there's another protein involved called the
Speaker 1: rh factor RH for reesus monkeys where it was first
Speaker 1: identified and the RH factor is either present plus or
Speaker 1: absent minus. Therefore, blood types are described as the type
Speaker 1: and the RH factor, such as O positive or A
Speaker 1: positive or A B negative. So how do they figure
Speaker 1: out what your blood type is? Blood types are determined
Speaker 1: by placing three drops of blood on a glass microscope
Speaker 1: slide to one drop of blood, a drop of antibodic
Speaker 1: solution to protein A known as anti A, is added.
Speaker 1: To the second drop, a drop of antibody solution of
Speaker 1: protein B is added, and to the third drop a
Speaker 1: drop of antibody solution to r H factor is added.
Speaker 1: The blood drops and the antibody drops are mixed and
Speaker 1: examined for clumps of red blood cells, and the blood
Speaker 1: type is determined by which blood cells form clumps. Clumps
Speaker 1: mean that the particular protein A, B, and r H
Speaker 1: is present. For example, clumps in anti A and anti
Speaker 1: r H but not in anti B would indicate a
Speaker 1: person with type A plus blood. Now, these clumps are
Speaker 1: important because that can happen in real life as well.
Speaker 1: When blood is given from one person to another, known
Speaker 1: as a transfusion, the blood types have to match. If
Speaker 1: they're not matched properly, the recipient will form these clumps
Speaker 1: in response to the donor's blood. The clots will lead
Speaker 1: to heart attacks, embolisms, and strokes. It's called a transfusion reaction.
Speaker 1: And when thinking about these reactions, two types are special.
Speaker 1: There's type OH minus blood. It's called the universal donor
Speaker 1: because it can be given to anybody. It has no
Speaker 1: proteins that can cause the clumps. And then there's type
Speaker 1: A B positive, which is known as the universal receiver
Speaker 1: because the recipient has all the proteins and so none
Speaker 1: of these clumps are going to form no matter what
Speaker 1: kind of blood is pumped in. Finally, the RH factor
Speaker 1: is important for pregnant women. If an RH positive man
Speaker 1: and an RH negative woman have a child, the child
Speaker 1: can be either RH positive or RH negative, depending on
Speaker 1: the GENA type of the father. If the baby is
Speaker 1: r H positive, this can cause problems because it's different
Speaker 1: from the mother's RH type. While in the womb, some
Speaker 1: blood cells from the baby will cross the placenta into
Speaker 1: the mother's bloodstream. The mother will make antibodies to the
Speaker 1: RH positive cells. If the woman becomes pregnant again, and
Speaker 1: if the baby is r H positive, the mother's anti
Speaker 1: RH antibodies will cross into the baby's blood and destroy
Speaker 1: its red blood cells, which can kill the baby. If
Speaker 1: diagnosed early, it's possible to save the baby under these
Speaker 1: circumstances by replacing the baby's blood with transfusion that are
Speaker 1: free of the r H antibodies. Also, if this situation
Speaker 1: is known, it's possible to treat an RH negative woman
Speaker 1: with an anti rh antibody drug immediately after childbirth to
Speaker 1: inactivate the baby's r H plus cells and prevent the
Speaker 1: mother from forming these anti rh antibodies in the first place.
Speaker 1: This is called desensitizing her to the RH factor. Be
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