1 00:00:00,520 --> 00:00:03,600 Speaker 1: Welcome to brain Stop from house stuff works dot com 2 00:00:03,600 --> 00:00:14,640 Speaker 1: where smart Happens. Hi, I'm Marshall Brain with today's question. 3 00:00:15,040 --> 00:00:19,680 Speaker 1: Are all blood types needed for donation? So let's start 4 00:00:19,680 --> 00:00:23,240 Speaker 1: at the beginning. A blood group or a blood type 5 00:00:23,480 --> 00:00:26,799 Speaker 1: is based on the presence or absence of two different 6 00:00:26,840 --> 00:00:30,360 Speaker 1: proteins called A and B on the surface of red 7 00:00:30,360 --> 00:00:34,919 Speaker 1: blood cells. Because there are two proteins involved, there are 8 00:00:34,960 --> 00:00:39,959 Speaker 1: four possible combinations or blood types known as A bio groups. 9 00:00:40,400 --> 00:00:44,800 Speaker 1: There's type A blood where only the A protein is present, 10 00:00:45,200 --> 00:00:48,760 Speaker 1: There's type B blood where only the B protein is present. 11 00:00:48,960 --> 00:00:53,080 Speaker 1: There's type A B blood where both proteins are present, 12 00:00:53,159 --> 00:00:56,600 Speaker 1: and then there's type O blood where neither protein is present. 13 00:00:56,960 --> 00:01:01,120 Speaker 1: And this is about the population. In addition to the 14 00:01:01,240 --> 00:01:05,320 Speaker 1: A and B proteins, there's another protein involved called the 15 00:01:05,480 --> 00:01:09,880 Speaker 1: rh factor RH for reesus monkeys where it was first 16 00:01:09,920 --> 00:01:14,720 Speaker 1: identified and the RH factor is either present plus or 17 00:01:15,000 --> 00:01:20,680 Speaker 1: absent minus. Therefore, blood types are described as the type 18 00:01:20,760 --> 00:01:23,840 Speaker 1: and the RH factor, such as O positive or A 19 00:01:24,040 --> 00:01:27,200 Speaker 1: positive or A B negative. So how do they figure 20 00:01:27,200 --> 00:01:30,600 Speaker 1: out what your blood type is? Blood types are determined 21 00:01:30,680 --> 00:01:34,360 Speaker 1: by placing three drops of blood on a glass microscope 22 00:01:34,440 --> 00:01:37,880 Speaker 1: slide to one drop of blood, a drop of antibodic 23 00:01:37,959 --> 00:01:41,960 Speaker 1: solution to protein A known as anti A, is added. 24 00:01:42,040 --> 00:01:44,400 Speaker 1: To the second drop, a drop of antibody solution of 25 00:01:44,480 --> 00:01:47,360 Speaker 1: protein B is added, and to the third drop a 26 00:01:47,440 --> 00:01:50,520 Speaker 1: drop of antibody solution to r H factor is added. 27 00:01:51,000 --> 00:01:53,880 Speaker 1: The blood drops and the antibody drops are mixed and 28 00:01:54,000 --> 00:01:57,320 Speaker 1: examined for clumps of red blood cells, and the blood 29 00:01:57,360 --> 00:02:01,720 Speaker 1: type is determined by which blood cells form clumps. Clumps 30 00:02:01,800 --> 00:02:04,800 Speaker 1: mean that the particular protein A, B, and r H 31 00:02:04,960 --> 00:02:09,720 Speaker 1: is present. For example, clumps in anti A and anti 32 00:02:09,919 --> 00:02:12,680 Speaker 1: r H but not in anti B would indicate a 33 00:02:12,800 --> 00:02:17,119 Speaker 1: person with type A plus blood. Now, these clumps are 34 00:02:17,120 --> 00:02:20,120 Speaker 1: important because that can happen in real life as well. 35 00:02:20,440 --> 00:02:23,280 Speaker 1: When blood is given from one person to another, known 36 00:02:23,320 --> 00:02:26,840 Speaker 1: as a transfusion, the blood types have to match. If 37 00:02:26,880 --> 00:02:30,960 Speaker 1: they're not matched properly, the recipient will form these clumps 38 00:02:31,080 --> 00:02:34,560 Speaker 1: in response to the donor's blood. The clots will lead 39 00:02:34,600 --> 00:02:39,400 Speaker 1: to heart attacks, embolisms, and strokes. It's called a transfusion reaction. 40 00:02:39,680 --> 00:02:43,400 Speaker 1: And when thinking about these reactions, two types are special. 41 00:02:43,840 --> 00:02:48,000 Speaker 1: There's type OH minus blood. It's called the universal donor 42 00:02:48,080 --> 00:02:50,799 Speaker 1: because it can be given to anybody. It has no 43 00:02:50,919 --> 00:02:54,400 Speaker 1: proteins that can cause the clumps. And then there's type 44 00:02:54,440 --> 00:02:57,600 Speaker 1: A B positive, which is known as the universal receiver 45 00:02:58,080 --> 00:03:02,040 Speaker 1: because the recipient has all the proteins and so none 46 00:03:02,040 --> 00:03:03,880 Speaker 1: of these clumps are going to form no matter what 47 00:03:04,000 --> 00:03:07,720 Speaker 1: kind of blood is pumped in. Finally, the RH factor 48 00:03:07,800 --> 00:03:12,080 Speaker 1: is important for pregnant women. If an RH positive man 49 00:03:12,240 --> 00:03:15,760 Speaker 1: and an RH negative woman have a child, the child 50 00:03:15,840 --> 00:03:19,919 Speaker 1: can be either RH positive or RH negative, depending on 51 00:03:20,000 --> 00:03:22,679 Speaker 1: the GENA type of the father. If the baby is 52 00:03:22,800 --> 00:03:26,600 Speaker 1: r H positive, this can cause problems because it's different 53 00:03:26,720 --> 00:03:30,480 Speaker 1: from the mother's RH type. While in the womb, some 54 00:03:30,600 --> 00:03:33,640 Speaker 1: blood cells from the baby will cross the placenta into 55 00:03:33,639 --> 00:03:37,280 Speaker 1: the mother's bloodstream. The mother will make antibodies to the 56 00:03:37,400 --> 00:03:41,720 Speaker 1: RH positive cells. If the woman becomes pregnant again, and 57 00:03:41,760 --> 00:03:45,000 Speaker 1: if the baby is r H positive, the mother's anti 58 00:03:45,200 --> 00:03:49,119 Speaker 1: RH antibodies will cross into the baby's blood and destroy 59 00:03:49,280 --> 00:03:52,640 Speaker 1: its red blood cells, which can kill the baby. If 60 00:03:52,680 --> 00:03:56,320 Speaker 1: diagnosed early, it's possible to save the baby under these 61 00:03:56,360 --> 00:04:00,839 Speaker 1: circumstances by replacing the baby's blood with transfusion that are 62 00:04:00,960 --> 00:04:04,920 Speaker 1: free of the r H antibodies. Also, if this situation 63 00:04:05,040 --> 00:04:08,080 Speaker 1: is known, it's possible to treat an RH negative woman 64 00:04:08,360 --> 00:04:12,920 Speaker 1: with an anti rh antibody drug immediately after childbirth to 65 00:04:13,000 --> 00:04:16,360 Speaker 1: inactivate the baby's r H plus cells and prevent the 66 00:04:16,400 --> 00:04:20,640 Speaker 1: mother from forming these anti rh antibodies in the first place. 67 00:04:20,800 --> 00:04:26,719 Speaker 1: This is called desensitizing her to the RH factor. Be 68 00:04:26,839 --> 00:04:29,440 Speaker 1: sure to check out our new video podcast, Stuff from 69 00:04:29,480 --> 00:04:32,320 Speaker 1: the Future. Join how Stuff Work staff as we explore 70 00:04:32,360 --> 00:04:37,240 Speaker 1: the most promising and perplexing possibilities of tomorrow. The house 71 00:04:37,240 --> 00:04:41,000 Speaker 1: Stuff Works iPhone app has arrived. Download it today on iTunes.