Transcript No Slide Title - University of Windsor

INTRODUCTION TO
PLATELETS
developed by
Liz Fracalanza
Tina Goodyear
Hugh B. Fackrell
Dept of Biological Sciences
University of Windsor
Windsor, ON Canada
OBJECTIVES
To examine the formed
elements of blood
To define the structure and
function of the cellular
elements
To differentiate between
the various blood cells
Introduction
Blood may be separated
into a clear fluid
composed of either serum
or plasma and formed
elements which contain
cells and cell fragments
Formed Elements of Blood
Thrombocytes (platelets)
Erythrocytes (red blood cells)
Leucocytes (white blood cells)
Prepartion of Blood
Prevent coagulation by the
addition of an anticoagulant
Smear blood onto a glass slide,
stain and examine under a
microscope
Use an oil immersion or a highdry objective
Use an area of the slide with
little red cell overlap
PLATELETS
Platelet Characteristics
Diameter
:2.9 - 4.3 um
Thickness :0.7 - 1.1 um
Cytoplasm :purple/blue-grey
Nucleus
:none
Life-span :8 - 12 days
Granules :Present(not visible)
Platelet Function
Maintain blood vessel integrity
Prevent blood loss to maintain
hemostasis
Synthesize chemical substances
 provide a reaction surface for
the coagulation cascade
Antibody - A specific immunoglobulin
(protein) produced by plasma cells
or B cells in response to a foreign
particle.
Anticoagulant - A substance that
inhibits blood clotting.
Basophilic - To have an affinity for
basic dyes such as methylene blue
used in the Wright stain.
Chemotaxis - A chemical
stimulation causing the movement
of a om the chemical source. It
is a part of the inflammation
response.
Chromatin - The stainable
material of the cell nucleus
composed of basic histones,
condensed nucleoprotein and
parachromatin
Coagulation - The series of chemical
reactions that result in blood
clotting.
Complement - Serum proteins that
participate in an enzymatic
cascade, resulting in a cytolytic
membrane attack complex.
Endothelial Lining - A layer of
cells that line the blood and
lymphatic vessels.
Hemostasis - An equilibrium of
blood cells and plasma required
to support life (homeostasis).
Heparin - An anticoagulant used to
inhibit the coagulation cascade by
enhancing the activity of antithrombin III.
Histamine - A vasoactive amine
secreted by the blood basophils
and mast cells when stimulated by
IgE antibodies.
Lymphokine - A protein released by
lymphocytes that acts as a
cellular mediator in the immune
response.