What blood type BB can be produced by each blood type

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　　From the perspective of the general public, there are four basic blood types: A\B\AB\O. The blood type of the parent determines the blood type of the child. The basic situation is as follows:

　　Parent's blood type The child's blood type

　　AxA A/O

　　AXB A/B/AB/O

　　AXAB A/B/AB

　　AхO A/O

　　BхB B/O

　　BхO B/O

　　BхAB A/B/AB

　　ABхO A/B

　　ABхAB A/B/AB

　　OхO O

　　Blood type refers to the different antigens contained on red blood cells. Red blood cells containing only A antigen are called type A, and those containing B antigen are called type B. Those with both A and B antigens are called type AB, and there is no A antigen. If there is no B antigen, it is called O type. ABO blood type is controlled by the three genes of ABO, A gene controls the production of A antigen, B gene controls the production of B antigen, O gene controls no A and B antigens, and the genes exist in pairs, and the genes that control ABO blood type may have There are six different combinations, namely AA, AO, BB, BO, AB, OO, and each person has only one of them. ABO blood group genes are also dominant and recessive. Genes A and B are dominant, and gene O is recessive. For example, if a person’s pair of genes is AA, the blood type is A. For example, a person’s pair of genes is AO, because the A gene is dominant and the O gene is recessive, the O gene cannot show its effect. The blood type of this person is also type A, and the same is true for the B gene. For example, when the pair of genes is AB, because the A gene and the B gene The genes are all dominant, and this person's blood type is AB type. Because the O gene is recessive, it can only be expressed when a pair of genes are O, then it is O blood .

　　When the blood type is passed to the offspring, the parent's reproductive cells (sperm and egg) each provide one of a pair of genes to form a pair of genes. If the father’s blood type is A, the pair of genes that control the blood type is AO. When sperm is formed, the AO pair of genes separate from each other and enter two sperms respectively, that is, the sperm with the A gene and the sperm with the O gene. . If the mother’s blood type is B, the pair of genes that control the blood type is BO. Similarly, when the egg is formed, an egg with the B gene and an egg with the O gene are formed. When fertilized, if the father’s sperm with the A gene is When the egg with the B gene is combined, it will form an AB individual (fetus), and the blood type is AB . If a sperm with O gene is fertilized with an egg with the B gene, an individual with the OB gene (fetus) will be formed, and its blood type is B The blood type is O type, if the sperm with O gene is combined with the egg with O gene and will form an individual with OO gene.

　　So, the answer is that all blood types are possible for children born with blood type a and blood type b.

　　Of course, this is only in terms of ABO blood type. Now a fifth blood type has been discovered in the world, called type C blood. Because this blood type is extremely rare, it is ignored here.