Exam 3: Blood Flashcards
Functions of blood
Transport of oxygen and carbon dioxide, nutrients, hormones, waste products
Regulation of body temp., blood pH, and osmolality of body fluids
Hemostasis
Immunity
Blood elements
Plasma, Erythrocytes (RBC), Leukocytes, Platelets (thrombocytes)
Hematocrit
RBC
45% of blood in males
40% of blood in females
55% of blood in newborns, decreases to 35% at 2 months, then elevates to adult values by puberty
Buffy coat
leukocytes and platelets
Serum
plasma without fibrinogen
Plasma
yellowish fluid, 90% water
Contains albumin, globulins, clotting proteins, complement proteins, lipoproteins, hormones, electrolytes, and dissolved gases
Albumin
maintains colloid osmotic pressure and transports
Pulls water into blood from tissues
Loss of albumin leads to edema
Erythrocytes
bioconcave disc - increases surface area to volume ration facilitating gas exchange
Small in diameter
4.2 to 6.1 million RBC per cubic mm
Only organelles are cytoskeletal components
Polycythemia
elevated erythrocyte count
Anemia
below normal erythrocyte count
Decrease in packed volume of erythrocytes or reduction in hemoglobin concentration
Erythrocyte transmembrane proteins
Glycophorin (A,B, & C) - unique to RBC
Band 3 - transports bicarbonate and chloride across plasmalemma (increases CO2 in blood) - antiporter
Band 4.1
proteins anchor cytoskeletal components by complexing with spectrin, glycophorin, and actin
Band 4.2
binds with Band 3 - forms a complex with ankyrin and spectrin
Adducin
promotes actin-spectrin association
Hereditary spherocytosis
mutations in ankyrin, band 3, spectrin, or band 4.2 that disrupt tethering interactions
Causes spherical shaped RBC - destroyed by spleen
Leads to anemia, jaundice, and splenomegaly
Elliptocytosis
caused by mutations in spectrin, protein 4.1, or glycophorin C
Antigens on surface of plasmalemma
determine blood type
A, B, AB, O
Rh - positive or negative
Erythroblastosis fetalis
Rh- mother forms antibodies against Rh antigen after birth of first Rh+ baby.
2nd Rh+ baby, mother’s antibodies will cross placenta and attach to erythrocytes of fetus
Mother receives Rho-GAM just before and after birth of first Rh+ baby to prevent disorder - contains antibodies against Rh antigen and will destroy Rh+ before mother can develop antibodies
Kell, Duffy, and Lewis antigens
immunogenic antigens
Can cause problems if not matched properly in transplants
Lewis only one don’t have to worry about matching
Duffy antigens
receptors for Plasmodium vivax and knowlesi - malarial parasites
Use antigens to enter RBC
Howell-Jolly bodies
small basophilic nuclear fragments in cytoplasm of RBC
Removed by macrophages in spleen
Present in patients with severe hemolytic anemia, dysfunctional spleens, or after splenectomy (spleen doesn’t remove them)
Heinz bodies
Seen in people with glucose-6-phosphate dehydrogenase deficiency
Inclusions of damaged hemoglobin from oxidative damage
Spleen macrophages remove Heinz bodies and damaged membranes = bite cells
Reticulocytes
immediate precursor to a mature erythrocyte
Cytoplasm has basophilic specks - clusters of ribosomes synthesizing hemoglobin
Increase in numbers mean body has demand for oxygen (hemorrhage, higher altitudes)
Leukocytes
White Blood Cells
Less in blood than Erythrocytes
Some contain specific granules - Neutrophils, Eosinophils, Basophils
Some are agranulocytes - lymphocytes and monocytes
Neutrophils
most abundant leukocyte
Bigger than RBC, lobated nuclei (3-5 lobes)
Phagocytic cells
Specific secondary granules are light pink - antimicrobial enzymes
Tertiary granules - gelatinase, cathespins, and glycoproteins (degrade basal lamina and ECM - migration of neutrophils into tissue)
Band cells
immature neutrophils - just released from bone marrow
Nuclei have band or rod shape
Elevated in acute bacterial infections (shift to the left)
Increase in band cells = increase in mature neutrophils
Azurophilic Primary granules
lysosomes
found in every type of leukocyte
Dohle body
dilated rER - basophilic component in peripheral cytoplasm of neutrophil
Seen in infections and other conditions
Eosinophils
Granulocyte, larger than RBC
Bilobed nucleus
Specific granules stain dark pink/red - contain substances that destroy parasites
Granules have white stripe down center of dark granule
Neutrophils are elevated in
bacterial infection,
inflammation
Eosinophils are elevated in
allergic reactions, parasitic infections, and inflammatory bowel disease
Basophils are decreased in
acute allergic reactions
Basophils
Least abundant in blood
S-shaped nucleus - obscured by basophilic specific granules
Specific granules are dark blue (or have white center with dark halo) - contain histamine & heparin
Originate from same precursor cell as mast cell - distinct cell populations
Agranulocytes
do not possess specific granules in their cytoplasm, do contain nonspecific, azurophilic granules (lysosomes)
Lymphocytes
Agranulocyte
Most numerous leukocyte in children under 8; 2nd most in people over 8
Most small, about size of RBC
Narrow rim of basophilic cytoplasm and small volume of organelles - mostly ribosomes
Prominent Nucleus
3 types of lymphocytes
B lymphocytes, T lymphocytes, and natural killer cells
lymphoctyes are elevated in
viral infection
Lymphocytic leukemia
Monocytes
Agranulocyte large cells Large kidney shaped nucleus Blue-gray cytoplasm Migrate into tissues - differentiate into macrophages
Platelets (thrombocytes)
fractured megakaryocytes
Function in blood clotting and tissue repair
Has 4 zones - Peripheral, Structural, Membrane, and Organelle
Peripheral zone
plasma membrane and glycocalyx
Structural zone
microtubules - shape of platelet
Actin and myosin monomers - polymerize and form contractile apparatus
Membrane zone
open canalicular system
Dense tubular system
Organelle zone
contains mitochondria, glycogen granules, peroxisomes, and lysosomal granules (alpha, delta, and lambda)
Monocytes are elevated in
inflammation
Neutrophils are decreased in
many viral infections, massive infection
Erythrocytes are elevated in
decreased oxygenation (high altitude, lung disease, heart disease); Renal carcinoma
Erythrocytes are decreased in
hemolytic and pernicious anemia;
Disruption of myeloid tissue (cancer, radiation)
Platelets are elevated in
splenectomy
Platelets are decreased in
Splenic sequestration (hypersplenism)
