Presentation on theme: "Agenda Chapter 19: Blood Lab 34.1 and “Blood Typing” Major functions"— Presentation transcript:
1Agenda Chapter 19: Blood Lab 34.1 and “Blood Typing” Major functions Major ComponentsStructure of RBCs and WBCsABO Blood Types, and Rh FactorLab 34.1 and “Blood Typing”
2Blood: General functions Transport of dissolved gases, nutrients, hormones, and metabolic wastesRegulation of pH, ion composition of interstitial fluidsRestriction of fluid loss at injury siteDefense against toxins and pathogensRegulation of body temperature
3Blood is Fluid Connective Tissue Recall that connective tissues are comprised of: specialized cells, extracellular protein fibers and fluid (ground substance)Matrix is a combo of the non-celluar componentsThe matrix of blood is called plasma
4Components of blood Plasma ~ 90% water ~ 10% dissolved (soluble) proteins most made by the liverFormed elements (cells and cell fragments) 1. RBCs 2. WBCs 3. Platelets
12RBCs CharacteristicsFunction primarily to carry oxygen and CO2 -contain hemoglobin (33% of cell weight)Lack a nucleusContain few organelles (no mitochondria)Can they generate ATP?? Make new protein?Shaped like biconcave discs -increases surface area for gas exchangeLife span approx. 120 daysFYI: 1 L of blood = ~ 5 million RBCs drop of blood = ~ 260 million RBCs
13Red Blood Cells~ 0.8 m~ 2.6 mmIncreased surface area, stackable, and flexible (can fit through 4 m capillaries)
14HemoglobinComposed of globin (protein) and pigment (heme) -Protein portion: 2 and 2 chains -Four heme units: contain iron and bind oxygen
16HematopoiesisMyeloid stem cellRate of RBC production controlled by erythropoietin (EPO)EPO produced by kidneys (upon exposure to low O2)EPO acts on stem cells of red bone marrow, and rate of maturationWhat is necessary for healthy RBCs?
17Fate of RBCs Life span of 100-120 days In 1 min: travel from periphery, are squeezed through capillaries, sent to heart and back!Become trapped in the spleen (eaten by macrophage) -heme degraded to biliverdin (green) -biliverdin converted to bilirubin (orange-yellow) -bilirubin binds to albumin, transported to liver for excretion in BILEAt large intestine, bacteria convert bilirubin to urobilinogens and stercobilinogensurobilins and stercobilins
19ABO Blood TypesABO system refers to the presence of surface antigens on the RBCs AND the antibodies in the plasmaAntigens also called agglutinogensAntibodies called agglutininsBA?
20ABO Blood Types A A B B Type A Type B Type AB Type O For a person with type A blood, the A antigens (surface proteins) inform the body’s defense system that “A” is “self”.For a persone with type A blood, which antigen(s) would alert the body as “non-self” or foreign?
21ABO Blood Types A A B B Type A Type B Type AB Type O When the body encounters “foreign” material, it generates antibodies against the surface antigens.When foreign RBC antigens are covered with antibodies, they clump and lyse (agglutination and hemolysis).What antibodies will each blood type have in the plasma?
28White Blood Cells (Leukocytes) Complete cells with nuclei and all organellesFewer than RBCs ( /ul)Critical to the body’s defense (immune system)Special features - Can migrate out of bloodstream - Capable of amoeboid movement -Atracted to specific chemical stimuli (respond by positive chemotaxis) -Capable of phagocytosis (Neutrophils, Eosinophils, Monocytes)
29Types of WBCs Neutrophils Eosinophils Basophils Monocytes Lymphocytes granulocytesagranulocytesNote that many of these cells have names that reflect the way these cells look when under the scope, when stained with certain dyes
30Neutrophils Account for 50-70% of circulating WBCs Dense segmented nucleus with 2-5 lobesHighly mobile, often the ‘first to arrive on the scene’following injuryAttack bacteria coated with antibodiesWhile active, release prostaglandins and leukotrienes
31Eosinophil 2-4% of WBCs Stain red, 2 lobed nucleus Attack cells coated with antibodiesImportantly, protect against parasites via exocytosis of toxic compounds
32Basophils Less than 1% Granules contain histamine, heparin Release enhances inflammation
33Monocytes2-8% of WBCsRemains in blood for 24hr before becoming a macrophage in tissueMacrophage=aggressive phagocytesWhile active, secrete chemicals that attract/stimulate other WBCsAlso secrete chemicals that attract fibroblasts into region
34Lymphocytes 20-30% of WBCs Note the round nucleus, little cytoplasm Most lymphocytes reside in connective tissue or lymphatic organsIn circulating blood: B cells, T cells, and NK cells
36PlateletsAnuclear cell fragments, contain cytoplasm and proteins (4 m diameter)“Pinched off” from megakaryocytes in bone marrowMajor participant in clotting response
37Hemostasis Highly regulated process of halting blood loss 3 phases Vascular phasePlatelet phaseCoagulation phase
38Hemostasis: Vascular phase Release of ADP and endothelinsCutting triggers smooth muscle contraction of vessel wallBasal lamina exposed to bloodstreamEndothelial cells release chemical factors, local hormones --ADP, endothelinsEndothelial cell membranes become ‘sticky’ --Platelets stick!