Blood Groups n n n Blood transfusions were
Blood Groups n n n Blood transfusions were not as successful until the discovery of blood types glycoproteins - large chemical complexes composed of carbohydrates and protein. Glycoproteins can be found on cell membranes determine blood type
Blood Groups. . . n n Blood types - A, B, AB, and O people with blood type: – A - have glycoprotein A on the red blood cell membrane – B - have B glycoprotein – AB - have both A and B marker proteins – O - has no marker proteins
Blood Groups. . . n n n What if an individual with blood type O received blood from somebody who had type A blood? The type O person’s body would recognize the markers on the type A cell membrane as foreign invaders The A marker is an antigen in the type O person’s body
Blood Groups… n n n Antigen - a substance, usually a protein in nature, that stimulates the formation of antibodies Antibodies - proteins formed within the blood that react with antigens antibodies attach to the antigen markers and cause the blood to clump
Blood groups. . . n n If blood type A was transfused to another person with type A blood would there be clumping? No, because the A antibody would recognize the A antigen as a friendly presence, part of the genetic make-up of the individual
Blood Groups. . . n n n Table 11. 2 - pg 278 summarizes the antigens and antibodies for each blood group If blood is transfused without a matching or acceptable donor type, the blood cells will agglutinate. Agglutinate - refers to the clumping of blood cells caused by antigens and antibodies
Blood groups. . . n n n Agglutinated blood cannot pass through capillaries Universal acceptor - People with type AB blood (their blood contains both A and B antigens) Universal donor - Type O blood can be received by individuals with all types of blood because it has no surface antigen
Blood Groups. . . n n n Even though people with type AB blood can accept any type, they can only donate to people with type AB blood People with type O blood may only accept from people with type O blood Fig. 11. 9 - pg 279
Rhesus Factor n n Rhesus factor is another antigen that is found on the membrane of the red blood cell People that have it are called Rh+ those who don’t have it Rh. People who are Rh- can donate to people who are Rh+ but cannot receive blood from Rh+ people
Rhesus Factor and Mothers… n n n Rhesus factor important in cases where there is an Rh- mother and an Rh+ baby condition called erythroblastosis fetalis can occur erythroblastosis fetalis - “blue baby” occurs when the mother’s antibodies against Rh+ blood enter the Rh+ blood of the fetus
Rhesus Factor and Mothers… n n the first Rh+ child of an Rh- mother is fine because the blood of the mother and the blood of the fetus are separated by the placenta - organ made from the cells of the baby and the cells of the mother. It is the site of nutrient and waste exchange between mother and baby.
Rhesus Factor and Mothers… n n although capillaries intertwine between the mother and the baby, their blood does not mix until birth during birth the placenta is removed from the uterus, the capillaries rupture and for the first time the blood of the baby, mixes with the blood of the mother
Rhesus Factor and Mothers. . . – the mother’s immune system begins to make antibodies when it recognizes the Rh+ antigen – If some of the antibodies move across the placenta of the 2 nd child they will attach to the Rh+ antigen and cause the baby’s blood to clump
– Results in clogging the capillaries and decreasing the amount of available oxygen for the baby(blue baby)
Treatment… n n transfusion of Rh- blood that has no antibodies, allowing most of the antibodies to breakdown before the baby produces Rh+ blood can also inject a mother with a drug that inhibits the formation of the Rh+ antibodies, the mother’s blood is then monitored during the pregnancy to see if any antibodies show up
Immune Response n n first line of defense: physical, chemical physical: – skin - protective barrier – respiratory passage - invaders trapped in mucous and swept away by cilia n chemical: – stomach acid destroys cells – Lysosyme - enzyme in human tears destroys cell walls of bacteria
Immune Response n cellular: – leukocytes seek out and destroy any invaders (neutrophils, eosinophils, monocytes) – appearance of foreign proteins in the body activates plasma proteins called complementary proteins – complementary proteins - help phagocytic cells(leukocytes) engulf foreign cells – fig. 11. 10 - pg. 281
Immune Response… n lymphocytes - antibody-producing white blood cells – fig. 11 - pg. 281 n two different types of lymphocytes: – 1. T cell - produced in the bone marrow and stored in the thymus gland • seeks out intruders and signals the attack – 2. B cells - lymphocytes that make antibodies
Antigen-Antibody Reactions n n n Antibodies - Y shaped proteins that are specific to the invader they attack tails are the same, arms are specialized the antibodies make the invader bigger and more easily engulfed by macrophages – macrophages - phagocytic white blood cells found in the lymph nodes or in the blood (in bone marrow, spleen, and liver)
Antigen-Antibody reactions… n Antibodies also cause invaders to clump together, making the whole mass too large to be able to pass through the cell membrane of the prospective host
Toxins and Poisons n poisons can attach themselves to cell membrane receptor sites. – Receptor sites - act as ports along cell membranes. Nutrients and other needed materials fit into specialized areas along cell membranes. n n Poisons can be mistaken for nutrients and are accidentaly taken into the cell Antibodies tie up the toxin so it cannot bind to the cell membrane
Viruses n viruses also trick the cells into taking them in – HIV - attaches to T-cell lymphocytes n n Why would the body have difficulty defeating HIV? Antibodies attach to viruses so that they cannot attach to the cell membranes of host cells – Sometimes the virus will mutate and the antibodies have to start all over again
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