Foundations II: Blood

functions of blood (4)
Click the card to flip 👆
1 / 139
Terms in this set (139)
layers of centrifuged blood (superficial to deep)plasma (clear/ yellow) Buffy coat (leukocytes aka white blood cells) erythrocytes (RBCs)if after harvesting blood it is allowed to clot, the fluid that would remain would be known asserum (essentially plasma minus any coagulation proteins or cells)the formed elements of blood consist of the ____ and ____ that reside therenucleated & non-nucleated cellsthe nucleated cells of the blood areleukocytes (white blood cells)non-nucleated cells of the blood arered blood cells & plateletsthe primary cell of the blooderythrocyte (RBC)erythrocytes are ____ cellsterminally differentiated cellsdo RBCs have nuclei?noRBCs cytoplasm is filled withhemoglobin - an O2 and CO2 binding proteinhemoglobin is made up of 2 elements1. heme - contains iron + binds O2 & CO2 2. large globular protein component (globin)the presence of so much hemoglobin within the RBC cytoplasm is what results in theuniformly eosinophilic staining of these cellshow does the loss of a nucleus and cytoplasmic organelles contribute to RBC function?the additional space allows more hemoglobin this allows more distribution of blood gassesthe shape of an RBC isbiconcave disc ~7-7.5 microns in diameterthe shape and relative thickness of the RBC provides a significant increase in ____surface area relative to volumethe shape of the RBC causes the thickness to be such that ____hemoglobin located anywhere within the cytoplasm of the RBC is a minimum distance from the plasma membrane surface (so gas exchange can occur)RBCs have the most studied ______ of any cellcell-membraneseveral proteins provide flexible support for the shape of an RBC as it travels throughout the circulatory system these proteins allow the RBC to _______ and ______deform into a cup shape and then spring back into the biconcave disc shapeseveral proteins provide flexible support for the shape of an RBC as it travels throughout the circulatory system what are they? (3)1. Band 3 2. ankyrin 3. spectrinband 3transmembrane ion transporter that is bound to ankyrin proteinsankyrin proteinslocated on the deep surge of the plasma membrane "anchor" to a protein called spectrinspectrinforms a latticework of fibrils deep to the plasma membraneas RBCs age, their membranes begin to show evidence ofdefects in the form of abnormalities in their shapeRBC abnormal shape can result fromdefective structural proteins (such as ankyrin or spectrin) or from dysfunction by ion transporters, such as band 3it is dangerous for RBCs to become non-uniform becausethey can become jammed into a small vessel and form an occlusion this can result in transient ischemiaeven the slightest abnormalities in the shape of RBCs results in them beingretained by the spleen and destroyedRBCs have several ____ on the surface of their plasma membranes these act as _____carbohydrate chains antigens for the immune systemthe carbohydrate chain antigens are commonly described as theABO blood type systemthe most common antigens are ____ a person can have ____A, B, O A, B, AB, Oa person's serum will contain ____ against any antigens that the person does not expressantibodiespeople who are AB are considered ____universal acceptors for blood donations, because they do not create antibodies against A or B antigenspeople with type O blood are considered _____universal donors, because their RBCs do not express A or B antigensIn addition to ABO, there is also ____ a person is described as being either ____ or ____Rh factor a person is either RH + or RH -combining Rh with the ABO system results in total blood types such as:A+, AB-, etc.Are most people Rh+ or Rh-?Rh+the most common blood types (1-3)1. O+ 2. A+ 3. B+hematopoesisthe process by which new RBCs are formedfor all cells of the blood, including RBCs, the starting point is in themarrow cavity of bonesRBCs are produced by a stem cell population known aspluripotent stem cellspluripotent stem cells are capable of differentiating intoany cell of the blood, but will undergo a differentiation process that selects a particular cell lineage (ex. erythrocyte or lymphocyte lineage)what are the final stages of RBC production (3)1. late normoblast (orthochromatic erythroblast) 2. reticulocyte 3. erythrocytewhat are the 2 precursor cells for RBCs1. orthochromatic erythroblast 2. reticulocyteunder normal conditions, orthochromatic cells are only found in thebone marrowdo orthochromatic cells have a nucleus?yes, but it has become highly condensed as the cell ceases to utilize it the cell will eject its nucleus (which will be consumed by macrophages) during the orthochromatic stage, but will still retain a small amount of ribosomesafter ejecting its nucleus, the orthochromatic erythroblast will become areticulocytereticulocytes appear largely identical to how do we tell their identity on a stainmature RBCs a special stain for ribosomesonce reticulocytes enter the blood from the bone marrow, they willfully mature into an RBC, shedding their remaining ribosomal elements in the processat any given moment, reticulocytes will constitute around ___ of circulating blood cells what does this reflect1% RBCs are destroyed at roughly the same rate at which they are producedduring periods of RBC destruction or loss, such as significant hemorrhage, what happens?increased numbers of reticulocytes will be observed in the bloodwhat are the 2 diseases of RBCs?1. anemia 2. sickle cellanemia what is it? what causes it (4)?low concentration of hemoglobin in the blood can be caused by: -diminished numbers of RBCs -diminished synthesis of hemoglobin caused by inadequate iron uptake - increased destruction of RBCs - hemorrhagesickle cellresults from a mutation in genes that form the global portion of hemoglobin causes an abnormal aggregation and polymerization of the hemoglobin - resulting in a sickled appearance or RBCs these altered RBCs are inelastic and are prone to causing infarctionsplatelets are akathrombocytesdo platelets have nuclei?noshape of plateletsdisc-like cell fragments ~2-4 micrometers in diameterplatelets break off from specialized cells from _____bone marrow, known as megakaryocytesfunction of plateletsclot formation they are able to assist in repairing small holes or leaks in blood vesselsplatelets circulate in blood for around ____ days10 on averagenormal amount of platelets per micrometer of blood is200,000 - 400,000platelets have 2 distinct regions1. outer lightly staining area (hyalomere) - contains a system of microtubules and filaments that help maintain the shape of the platelet 2. inner region (centromere/ granulomere) - where the darkly staining granules are locatedplatelets are very sticky to _____exposed collagen fibers that they encounter (under normal conditions, collagens would not be exposed to the contents of blood vessels, so this feature makes platelets well equipped to adhere to areas of vascular damage or leaks)the stickiness of platelets is due to (2)1. the abundant carbohydrates in their plasma membrane 2. behavior whereby they release many clotting factors and proteins rapidly after coming into contact with collagen fibers or other elements of connective tissuein addition to being sensitive to areas of vascular damage, platelets contain a system of _____ and _____actin and myosin proteinsafter platelets have formed a clot, and have found to each other and to the edges of the supposed injury site, what happens?the acton and myosin proteins within their cytoplasm allow platelets to retract, thereby helping to pull the edges of the wound together to initiate wound healingplatelets are derived from what cellslarge cells in the bone marrow known as megakaryocytesmegakaryocytes are huge cells that contain a ____ and _____large nucleus several visible nucleoliwhere are megakaryocytes foundbone marrowwhere are megakaryocytes located on a stainnear blood sinusoids (indicated by the open white spaces in the image)how do megakaryocytes produce platelets?They extend cytoplasmic processes, called proplatelets, towards vascular sinusoids the protoplatelets pinch off fragments which are released into the blood as plateletsnon-formed elements (specific) 2plasma serumformed elements (specific) 3RBCs platelets leukocytesleukocytes branch intogranulocytes agranulocytesgranulocytes (3)neutrophils, eosinophils, basophilsagranulocytes (2)lymphocytes monocytesleukocytes are the ____ of the bloodnucleated cellsleukocytes akawhite blood cellsleukocytes ______ before exiting the blood in order to travel to sites of _____circle through the body infection, were they exert their immunological effectsthere are 2 main classes of leukocytes that are classified according to (2) what are they?1. shape of nuclei 2. type of cytoplasmic granules they contain granulocytes + agranulocytesgranulocyte structuremulti-lobed nuclei cytoplasm contains numerous secretory granulesgranulocyte secretory granules come in 2 varieties1. specific granules - have special functions and stain differently for each of the 3 types of granulocytes 2. azurophilic granules - that stain a dark bluish color, and are lysosomes common to many types of leukocyteswhat is the most common type of leukocyte in the blood?neutrophils (60-70% of WBCs)function of neutrophilsfirst responder cells of the innate immune system, the body's first line of defense against bacterial infectionneutrophil structurelobed nucleus (common to granulocytes) cytoplasm filled with secretory granules and lysosomesunlike other granulocytes, the secretory granules of the neutrophil do not _____stain particularly well, making the lobed nucleus of these cells the most prominent featureneutrophils get their name from the fact that theircytoplasmic granules do not stain particularly well with most preparations, making their multi-lobed nucleus their most prominent featurethe specific granules of neutrophils contain____ (2)1. cytokines for acute inflammation that attract other leukocytes to the site of infection 2. enzymes important for allowing neutrophils to travel through tissue (collagenases)the specific granules of neutrophils are released into the _____ during _____extracellular environment inflammationare the azurophillic granules more or less numerous than specific granules in neutrophils?morethe azurophilic granules of neutrophils are ____ they contain (2)large lysosomes 1. typical lysosomal enzymes 2. enzymes that produce reactive oxygen species (free radicals) - myeloperoxidaseneutrophils act against bacteria in a variety of ways (2)1. phagocytic cells - devour bacteria 2. release reactive oxygen generating compounds + lysozyme into extracellular environmentreactive oxygen species and lysosomal enzymes are very damaging to (2)bacteria cell walls but also to the body's own tissues - significant damage can be inflicted to normal healthy tissue as a byproduct of neutrophil activityshortly after neutrophils arrive to a site of infection and phagocytose everything, what happens?they destroy themselves via apoptosiswhat are the main components of pusneutrophils, dead neutrophils, and dead bacterianeutrophils are born from precursor cells in ____bone marrow (just like other blood cells)the developmental stage that is just prior to a neutrophil is known as astab cell/ band cellstab cell structuregranulated cytoplasm (like adult neutrophil) nucleus - has not completed its development into the final multi-lobed form (so has elongated and somewhat irregular nucleus)under normal circumstances, how many stab cells should be in the blood?few, if anywhen are stab cells released prematurely into the blood from the bone marrow?only during periods where the body's pool of neutrophils are being depleted by infectioneosinophils are recognized by theeosinophilic staining of their cytoplasmic granuleseosinophils structurenuclei = multiple lobes cytoplasmic granuleseosinophils represent ____ % of circulating leukocytes under normal conditions1-3eosinophils respond toparasitic infections (parasitic worms in particular)eosinophil granules contain a neurotoxin designed to kill parasites known aseosinophil-derived neurotoxineosinophils also play a role in _____ and will be seen in increased numbers in people with conditions like ___allergic reactions asthmabasophils make up ____% of circulating leukocytesless than 1% (thus it is very difficult to find in blood smear preparations)basophil structurethe multi lobed nucleus of basophils is difficult to appreciate due to the darkly staining specific granulesfunction of basophils is similar tomast cellsfunction of basophilsgranules contain heparin, histamine, leukotriene basophils are able to migrate out of the blood into connective tissue and supplement the actions of mast cellsas granulocyte precursor cells differentiate, they accumulate ____specific and azurophilic granules in their cytoplasmas granulocyte precursor cells differentiate and the nucleus becomes ___progressively less spherical and more elongated, eventually becoming multi-lobedmonocytes are the precursor cells to ____macrophages of various tissues and organsin the blood, monocytes have what nucleus appearanceindented or kidney-bean shaped nucleusdo monocytes exert effects in the blood?noonce monocytes leave the blood they enter ___ or ___connective tissue parenchyma of an organonce monocytes enter connective tissue or parenchyma of an organ, they ____terminally differentiate into various subtypes of macrophageswhat are the subtypes of macrophages (4)1. Kupffer cells in the liver 2. microglia in the CNS 3. alveolar macrophages in the alveoli of the lungs 4. osteoclasts in bonelymphocytes are relatively small cells compared to ____ and ____ they also have a large _____ ratiomonocytes and granulocytes nuclear: cytoplasmic (have little cytoplasm relative to their nucleus)lymphocytes comprise ___% of the leukocytes in circulation at any given time20-50what is the 2nd most commonly observed leukocyte?lymphocyteswhat is the only class of leukocytes that are able to both leave the blood and re-enter the blood at a later time?lymphocyteslymphocytes have a lifespan ofseveral days to several years, depending on the specific subtype of lymphocytelymphocytes come in 3 basic types based on the surface molecules they express1. T lymphocytes 2. B lymphocytes 3. NK cellsB & T lymphocytes are the only cells that have the ability to ___recognize specific epitopes (10^18 different)can we differentiate the various types of lymphocytes using light microscopy alone?nohow can we distinguish different types of lymphocytes?using immunohistochemical stains for their surface receptors, or by their locations in various tissueslymphocytes are born in thebone marrowB lymphocytes become immunocompetent where?in the bone marrowT lymphocytes are born in the _____ and migrate to the _____, where they gain immunocompetencybone marrow thymuswhat is CBC?complete blood count a blood testCBC measures (7)1. hemoglobin in the blood 2. hematocrit (% RBCs in the blood) 3. WBC count 4. WBC differential (% of each leukocyte) 5. % reticulocytes 6. platelet count 7. morphological description of RBCs