A&P Unit 3 Blood Lab

12,13,14, and 15 BLOOD TYPING

Blood types are based on interactions between antigens and antibodies ANTIGENS: *Complex molecules on the surface of cell membrane that are unique to the individual -Used to distinguish self from foreign matter -Foreign antigens generate an immune response -Agglutinogens: antigens on the surface of the RBC that is the basis for blood typing -called antigen A and B and are determined by carbohydrate moieties found on RBC surface ANTIBODIES *proteins (gamma globulins) secreted by plasma cells -part of immune response to foreign matter -binds to antigen and mark them for destruction -form ANTIGEN-ANTIBODY COMPLEX -Agglutinins: antibodies in the plasma that bring about transfusion mismatch -Found in PLASMA - Anti-A or Anti-B (both or none found in plasma) -appear 2-8 months after birth -you do not form antibodies against your antigens -you automatically form antibodies against the antigens you dont display (this is unusual) AGGLUTINATION: -antibody molecule binding to antigen -causes clumping or RBC -each antibody can attach to several foreign antigens on several different RBC at the same time -responsible for mismatched transfusion -agglutinated RBC block small blood vessels, hemolize, and release hemoglobin over the next few hours or days -HB blocks kidneys tubules and causes acute renal failure Blood type A has A antigens Blood type B has B antigens Blood type AB has both AB antigens Blood type O has neither antigen Universal donor: TYPE O Universal recipient: TYPE AB RH GROUP: RH D is the most reactive and a patient is considered RH positive if they have the D antigen ANTI D AGGLUTININS NOT NORMALLY PRESENT: -Form in RH negative individuals exposed to RH positive blood

11. Anemia

Causes of anemia fall into 3 categories: *Inadequate erythropoiesis or hemoglobin synthesis -kidney failure and insufficient erythropoietin -iron deficiency anemia -Inadequate vitamin B12 from poor nutrition or lack of intrinsic factor(pernicious anemia) *Hypoplastic anemia: slowing of erythropoiesis *Aplastic anemia: complete cessation of erythropoiesis -Hemorrhagic anemia: from bleeding -Hemolytic anemia: from RBC destruction ANEMIA HAS THREE POTENTIAL CONSEQUENCES: *Tissue hypoxia and necrosis -patient is lethargic -shortness of breath upon exertion -life threatening necrosis of brain, heart, and kidney *Blood osmolarity is reduced producing tissue edema *Blood viscosity is low -heart races and pressure drops -cardiac failure may ensue SICKLE CELL DISEASE: *Herditary hemoglobin defect that occurs mostly among people of African decent -caused by recessive allele that modifies the structure of hemoglobin -does not bind oxygen well -RBC becomes rigid, sticky, and pointed at ends -clump together and block small blood vessels causing intense pain -can lead to kidney or heart failure, stroke, rheumatism, or paralysis

Red Blood Cells (RBC)

Erythrocytes- most numerous of formed elements. mature erythrocytes do not contain a nucleus or other organelles. filled with hemoglobin. referred to as biconcave disk. RBC will appear pinkish with a a pale center. large quantity.

20. clotting cascade extrinsic

Initiated by release of tissue thromboplastin (factor 3) from damaged tissue -Cascade to factor VIII, V, and X (FEWER STEPS):

18. clots (prevention)

PLATELETS DEAL WITH CLOTTING FACTORS: Hemostatsis: 3 pathways -vascular spasm: prompt constriction of a broken vessel: this pathway allows time for the other 2 pathways -Platelet plug formation: *broken blood vessels exposes collegen *platelet pseudopods stick to damaged vessel and other platelets, pseudopods contract and draw walls of vessels together forming a platelet plug -Coagulation: last and most effective defense against bleeding *conversion of plasma protein fibrinogen into insoluble fibrin threads to form framework of clot *Procoagulants(clotting factors) usually produced by the liver are present in plasma *activate one factor and it will activate the next to form reaction cascade *Platelets degranulate releasing a variety of substances: -Serotonin is a vasoconstrictor -ADP attracts and degranulates more platelets -Thromboxane A2, an eicosanoid, promotes platelets aggregation, degranulation, and vasoconstriction POSITIVE FEEDBACK CYCLE IS ACTIVE UNTIL BREAK IN SMALL VESSEL IS SEALED.

erythrocytes

RBC- 5millionmm- transport of oxygen and carbon dioxide

16. anatomy of blood cells

RBC: disc shaped cell with thick rim -lose nearly all organelles during development -Lack mitochondria(anaerobic fermentation to produce ATP) -Lack nucleus and DNA(no protein synthesis or mitosis) LEUKOCYTES: -conspicuous nucleus -retain their organelles for protein synthesis -Granules: *all WBC have lysosomes called nonspecific granules: inconspicuous cytoplasm looks clear *granulocytes have specific granules that contain enzymes and other chemicals employed in defense against pathogens PLATELETS: small fragments of megakaryocyte cells. -2-4 diameter and contain granules -complex internal structure and open canalicular system -Amoeboid movement and phagocytosis

17. Hemolytic disease of the newborn

RH antibodies attack fetal blood causing severe anemia and toxic brain syndrome

19. Thrombus vs Embolus:

Thrombus: clot that mostly occur in leg veins of inactive people Pulmonary embolism: clot may break free, travel from vein to lungs Embolus: anything that can travel in the blood and block blood vessels Infarction: Tissue death may occur if clot blocks blood supply to an organ

leukocytes

WBC-5-10 thousandmm. protection against pathogens

neutrophils

attack and destroy bacteria 50-70%

monocytes

becomes macrophages and engulfs large foreign particles 2-8%

red blood cell count

can be used to determine anemia as well as abnormalities in the red blood cells or conditions affecting erythrocytes. a normal red blood cell count is recorded as the number of cells per microliter. normal for males is 4.7-6.1 females. 4.2-5.4 million cells per mcL

White Blood Cells (WBC)

leukocytes- not numerous. 5 different types, different appearance under microscope. to view, must be stained. most common stain will look purple. very obvious nucleus

hemoglobin

major component of red blood cells. responsible for the transport of oxygen, and when combined with oxygen gives the red blood cell its color, measuring hemoglobin is a good indication of the bloods ability to carry oxygen throughout the body.

hematocrit (HCT)

measurement of the proportion of blood that contains the red blood cells. to determine hematocrit a micro capillary is filled with blood. type is then centrifuged to separate plasma and formed elements. then value is read. normal value 42-52 male. 37-47 female. dehydration, COPD or erythrocytosis can increase hematocrit. can decrease in anemia cirrhosis, hemorrhage, bone marrow failure, renal failure.

Platelets/ thrombocytes

not cells, they're fragments of cells. not noticeable on blood smear. stained purple. appear as flecks on slide.

basophils

promotes inflammation and healing of wounds 1%

white cell differential count

reports each type of leukocyte as a percentage of the total white blood cell count

eosinophils

responds during allergic reactions and parasitic infections 2-4%

lymphocytes

responsible for specific immunity, respond to bacterial and viral infections. 20-40%

platelets

thrombocytes- 150-450 thousandmm. involved in blood clotting