The Blood

Ch. 19The BloodObjectivesDescribe the functions of the blood.Describe the physical characteristics and principal components of blood.

BloodBlood connective tissue composed of a liquid matrix called blood plasma that dissolves and suspends cells and cell fragments

Blood FunctionsTransportationOxygen from lungs to body cellsCarbon dioxide from body cells to lungsNutrients from GI tract to body cellsHormones to body cellsHelps eliminate heatRegulationRegulates pHTemperatureOsmotic control of cellsProtectionClottingWhite blood cells - diseaseComponents of BloodBlood plasma (55%) extracellular matrix that contains dissolved substancesStraw-colored liquid, mostly water, some proteins (antibodies)Formed elements (45%) cells and cell fragmentsRBCs, WBCs, and plateletsIf blood is centrifuged cells sink to the bottom

Components of Blood

Red Blood CellsErythrocytesContain hemoglobinOxygen-carrying proteinFunction in oxygen/carbon dioxide gas exchange

White Blood CellsHave nuclei, do not contain hemoglobinDifferent typesEosinophil, basophil, neutrophil, lymphocyte, monocyteFunction in fighting infection, invaders, sometimes own cells (auto-immune disorders)Cells leave blood vessels by squeezing between endothelial or epithelial tissueUse enzymes or phagocytosis to destroy bacteriaWBC

PlateletsStop blood loss from damaged blood vessels by forming a platelet plugThen release proteins that promote blood clottingUsually live 5-9 days

Platelets

ReviewWhat are the functions of blood?What are the physical characteristics of blood?What are the primary components of blood and what do they do?ObjectivesDistinguish between ABO and Rh blood groups.Explain why it is so important to match donor and recipient bloody types before administering a transfusion.Blood TypesBlood cells have surface markers called antigensABO Blood GroupRBC with A antigens A blood typeRBC with B antigens B blood typeRBC with A and B antigens AB blood typeRBC with no antigens O blood typeBlood TypesBlood plasma contains proteins called antibodiesAntibodies will react with antigens if mixedType A blood A antigens, anti-B antibodiesType B blood B antigens, anti-A antibodiesType AB blood A and B antigens, no antibodiesType O blood no antigens, anti-A and anti-B antibodiesBlood Types

TransfusionsTransfusion transfer of whole blood or blood components (RBC or plasma)Agglutination clumping of RBCs, hemolysis occurs, kidney damage and death can resultThis only causes problems between recipient antibodies and donor antigensDonor antibodies become diluted in blood plasmaExample(recipient) A person receives blood from (donor) B personRecipients blood contains anti-B antibodiesDonors blood contains B antigensAntigen/antibody complex forms

Who can donate/receive to/from who?

Rh Blood GroupAntigen was discovered in the rhesus monkeyRh+ people have the Rh antigen, Rh- people do not have the Rh antigenPeople do not naturally have anti-Rh antibodiesIf Rh- person receives blood from Rh+ person, immune system will make anti-Rh antibodiesIf they receive Rh+ blood again, the anti-Rh antibodies will cause agglutinationWho can donate/receive to/from who?+ should not be given to + can receive + or - can give to + or Universal donor O-Universal recipient AB+Hemolytic Disease of Newborn (HDN)Fetal blood can cross placenta into maternal blood streamIf baby is Rh+ and mother is Rh-, mothers immune system starts making anti-Rh antibodiesDuring the next pregnancy the antibodies can cross into the fetal bloodIf the second fetus is Rh+, agglutination can occurHDN

ReviewWhat are the different blood groups? Which antigens/antibodies does each group have?Why does this matter during transfusions?What is HDN? How is it caused?

Review of InheritanceBlood type Punnett squaresRh Punnett squares Rh+ is dominant to Rh-Rh+ could have Rh+/Rh+Rh + could have Rh+/Rh-Rh- must be Rh-/Rh-