Histology: Blood

Front 1

What differentiates agranulocytes histologically from granulocytes?

Back 1

agranulocytes don't possess specific granules or have lobed/segmented nuclei

Front 2

How are T cells and B cells differentiated histologically?

Back 2

they can't be differentiated histologically, they can only be differentiated immunocytochemically based on cell surface markers

in H&E stain, will generally be lymphocyte

Front 3

What are the components of intercellular fluid of blood?

Back 3

serum and plasma

Front 4

What are the major proteins in plasma?

Back 4

albumin - essential for maintenance of blood osmotic pressure

globulins - antibodies

fibrinogen - essential for clotting

Front 5

What is the function of blood?

Back 5

transport O2 and CO2

helps maintain homeostasis: body T, pH, and osmotic balance

Front 6

What are the proteins of RBC plasmalemma and why are they important?

Back 6

spectrin, ankryin, band 3 protein, and glycophorin

important for flexibility of RBC

Front 7

What are reticulocytes and their characteristics?

Back 7

young RBCs with residual rRNA

Front 8

Are leukocytes permanent or transient components of blood? What are their functions?

Back 8

transient, they serve their function in tissues

function in defense against foreign materials and participate in inflammatory reaction and immune responses

Front 9

What cells make up the leukocytes?

Back 9

neutrophils, eosinophils, and basophils, lymphocytes, and monocytes

Front 10

What are the types of leukocytes?

Back 10

granulocytes and agranulocytes

Front 11

What cells make up the granulocytes?

Back 11

neutrophils, basophils, eosinophils

Front 12

What are the primary functions of neutrophils?

Back 12

phagocytosis and kill bacteria (therefore can survive in anaerobic environments)

Front 13

What are the histological characteristics of neutrophils?

Back 13

2-5 lobed nucleus
salmon-pink granules (specific)
larger purple granules (azurophilic)
Barr body in females

Front 14

What are stab/band cells?

Back 14

immature neutrophils, will have horseshoe-shaped nuclei

Front 15

What is a "shift to the left"?

Back 15

appearance of large number of stab/band cells in circulating blood, indicative of bacterial infection

Front 16

What occurs in neutrophils during phagocytosis?

Back 16

production of superoxide, hydrogen peroxide, and nitric oxide

Front 17

What are the primary functions of eosinophils?

Back 17

phagocytosis of antigen-antibody complexes

moderation of allergic response

killing of parasitic worms

Front 18

What are the histological characteristics of eosinophils?

Back 18

bilobed nucleus
orange-red granules (specific)
granules have crystalline core in EM

Front 19

What proteins are contained in the specific granules of eosinophils?

Back 19

internum - major basic protein (arginine-rich)

externum - acid phosphatase, arylsulfatase, RNAse, phospholipase, peroxidase, cathepsin, glucoronidase

Front 20

What is the primary function of basophils?

Back 20

mediation of inflammatory reactions

Front 21

What are the histological characteristics of basophils?

Back 21

2-3 lobed nucleus, but difficult to see if not EM
large, irregular purple specific granules

Front 22

What do the specific granules of basophils contain?

Back 22

heparin, histamine, leukotrienes

Front 23

In EM, how would one differentiate b/t the different granulocytes?

Back 23

neutrophils - 2-5 lobed nuclei (most lobed) and small specific granules
eosinophils - bi-lobed nuclei and large specific granules with crystalline core
basophils - 2-3 lobed nuclei and large, dark, irregular specific granules

Front 24

What are B cells?

Back 24

bone marrow-derived cells that have surface immunoglobins (antibodies) that recognize antigens

fxn in humoral immunity - differentiate into plasma cells for antibody production or form memory B cells

Front 25

What are T cells?

Back 25

thymus-derived cells that have surface T cell receptors (not antibody) that recognize antigens

fxn in cell-mediated immunity, secrete lymphokines that modulate macrophage function

Front 26

What are the different types of T-cells and their function?

Back 26

helper T cells: release lymphokines and interleukines that stimulate B cells

cytotoxic T cells: recognize foreign antigens, secrete lymphokines that leads to lysis of infected cell

suppressor T cell: suppress antibody formation by B cell and suppress immune response to self molecules

memory T cells

Front 27

What are null (NK) cells?

Back 27

no B surface marker

circulating stem cell or natural killer cells

Front 28

What are the functions of monocytes?

Back 28

Differentiate into the various macrophages of the mononuclear phagocyte system. The macrophages phagocytose and present antigens to helper T cells.

Front 29

What are the functions of platelets?

Back 29

Stop bleeding, form temporary plug, and induce repair by inducing proliferation of endothelial and smooth muscle cells

Front 30

What are the four zones of organization of platelets?

Back 30

peripheral zone - cell membrane with glycocalyx coat

structural zone - cytoskeletal elements to maintain shape

organelle zone - organelles and granules (alpha, delta, lambda)

membrane zone - channels that communicate along compartments and control calcium concentration

Front 31

What are alpha granules?

Back 31

large granules containing fibrinogen, platelet-derived growth factor, and several other proteins

Front 32

What are delta granules?

Back 32

dense bodies containing ADP, ATP, and calcium; they store serotonin from the plasma

Front 33

What are lambda granules?

Back 33

small vesicles and contain lysosomal enzymes important for removing early repair products

Front 34

What are lymphocytes?

Back 34

most common agranulocyte

function in immune responses

common in connective tissue, lymphoid tissue, and organs

Front 35

What are the structure of lymphocytes?

Back 35

small lymphocyte - spherical nucleus, condensed chromatin, thin rim of basophilic cytoplasm, few azurophilic granules

medium & large lymphocyte - larger in diameter, have more cytoplasm and less heterochromatic nuclei; activated lymphocytes

Front 36

What is the repair process when blood vessels are damaged?

Back 36

1. underlying connective tissue exposed to circulating platelets
2. primary aggregation of platelets triggers their degranulation
3. platelets release ADP and thromboxane A2 (induce further aggregation) and serotonin (vasoconstrictor)
4. primary hemostatic platelet plug forms
5. platelets induce fibrinogen to form fibrin clot
6. second hemostatic plug/thrombus
7. clot retracted via platelet actin and myosin with ATP
8. platelet-derived growth factor (PDGF) stimulated proliferation of fibroblasts and smooth muscle cells for repair

Front 37

What is anemia?

Back 37

any condition characterized by a low count of normal RBCs or decreased amount of hemoglobin in peripheral blood

Front 38

What are the causes iron deficiency anemia?

Back 38

impaired hemoglobin production resulting from low iron intake, chronic blood loss, or increased demand for iron (e.g. in pregnancy)

Front 39

What are the causes of pernicious anemia?

Back 39

impaired production of RBCs resulting from vitamin B12 deficiency because of inadequate synthesis of intrinsic factor

Front 40

What are the causes of sickle cell anemia?

Back 40

production of abnormal hemoglobin (HbS) resulting from mutation in beta chain; autosomal recessive disease

Front 41

What causes of hereditary spherocytosis? What are the results?

Back 41

mutation in spectrin (cytoskeletal protein) causing defect in RBC membrane; usually autosomal dominant

results in fragile, round hyperchromatic RBCs sensitive to lysis

Front 42

What causes beta-thalassemia? What are the results?

Back 42

various mutations in hemoglobin beta chain; autosomal recessive

results in small, pale, short-lived RBCs