FORMED ELEMENTS OF BLOODFORMED ELEMENTS OF BLOOD

BLOOD IS A CONNECTIVE BLOOD IS A CONNECTIVE TISSUE!TISSUE!

• Has all 3 components expected of any CT– Fibers are latent as soluble precursor

• Fibrinogen– Fibrin of clots

– Matrix is liquid plasma– Cells are collectively the “formed elements”

• True cells are not “blood” cells at all– Use blood only for transport– Active only in extravascular spaces of CT

• Non-cells are active in blood– Erythrocytes– Platelets

ERYTHROCYTESERYTHROCYTESA/K/A “RED BLOOD CELLS”A/K/A “RED BLOOD CELLS”

• Uniform size• Biconcave

disks• Flexible• Enucleated

– Endpoint of a developmental series of nucleated precursors

• No organelles!– Limited Life

RBC’sImpartthe color to blood due to Hgb

ERYTHROCYTESERYTHROCYTES• “Red blood cells”– Not cells

anymore– Most

numerous formed element

– Oxygen transport only function

– Senescent after 90-120 days

PLATELETSPLATELETS

• Cell fragments– Precursor in

bone marrow

• Responsible for intial clot formation

• Smallest formed element

PLATELETS PLATELETS IN ACTIONIN ACTION

GRANULOCYTES: NEUTROPHILSGRANULOCYTES: NEUTROPHILS

• Multilobed nucleus• Granules in

cytoplasm– Lysosomes

• Most numerous of granulocytes

• Phagocytic• First cell of

inflammation response

GRANULOCYTES: NEUTROPHILSGRANULOCYTES: NEUTROPHILS

• In situ appear smaller

• Nuclear configuration is clue

• Found in circulatory spaces

• Found in CT’s especially in inflammation

GRANULOCYTES: EOSINOPHILSGRANULOCYTES: EOSINOPHILS

• Prominent granules

• Bilobed nucleus• Phagocytic

– Ag/Ab complexes

• Visible in sites of allergic responses

• Species differences in numbers and granule sizes

NEUTROPHIL & EOSINOPHILNEUTROPHIL & EOSINOPHIL

GRANULOCYTES: BASOPHILGRANULOCYTES: BASOPHIL

• Rarest cell of blood– Absent in some

species

• Precursor of Mast Cell of CT– Granules

contain histamine & heparin

BASOPHIL & MAST CELLBASOPHIL & MAST CELL

Basophil in Smear, Wright Stain

MastCellsH&E

MastCellsTB

AGRANULOCYTES: LYMPHOCYTEAGRANULOCYTES: LYMPHOCYTE

• Almost no cytoplasm

• Nucleus condensed & inactive

• Quiescent cell in transit to CT– Immune

response functions

LYMPHOCYTE & PLASMA CELLLYMPHOCYTE & PLASMA CELL

AGRANULOCYTES: MONOCYTEAGRANULOCYTES: MONOCYTE• Very large cell• More

cytoplasm than lymphocyte

• Precursor to macrophages of CT

• Indented “spaghetti & meatballs” nucleus

Sekian Makasih..