Overview Flashcards
The average human possesses_____ of blood.
5 liters
Purpose of Blood (4)
transports oxygen from lungs to tissues
clears tissues of carbon dioxide
transports glucose, proteins, and lipids
moves wastes to the liver and kidneys
The liquid portion is_______which, among many components, provides coagulation enzymes that protect vessels from trauma and maintain the circulation.
plasma
Purpose of plasma
provides coagulation enzymes that protect vessels from trauma and maintain the circulation.
transports and nourishes blood cells.
Plasma
There are three categories of blood cells:
red blood cells (RBCs), or erythrocytes
white blood cells (WBCs), or leukocytes
platelets (PLTs), or thrombocytes
Study of blood cells
Hematology
is ordered on nearly everyone who visits a physician or is admitted to a hospital.
complete blood count (CBC)
The first scientists, such as______ in ____, described “worms” in the blood
Athanasius Kircher in 1657
______ in ____gave an account of RBCs
Anton van Leeuwenhoek in 1674
In the late 1800s that______ described platelets as “______”
Giulio Bizzozero
petites plaques
The development of the Wright stain by ______ in ____opened a new world of visual blood film examination through the microscope.
James Homer Wright in 1902
Although automated analyzers now differentiate and enumerate blood cells,_________ stain (polychromatic, a mixture of acidic and basic dyes), and refinements thereof, remains the foundation of blood cell identification.*
Wright’s Romanowsky-type stain
In the present-day hematology laboratory, RBC, WBC, and platelet appearance is analyzed through automation or visually using 500× to 1000x _______examination of cells fixed to a glass microscope slide and stained with______ or _______ stain
light microscopy
Wright or Wright-Giemsa
The scientific term for cell appearance is morphology, which encompasses (5)
cell color
size
shape
cytoplasmic inclusions
nuclear condensation
_____ are anucleate, biconcave, discoid cells filled with a reddish protein,______, which transports _____ and _____
RBCs
Hemoglobin
oxygen and carbon dioxide
RBCs appear _____ (color) and measure______ in diameter with a zone of pallor that occupies one third of their center, reflecting their biconcavity
salmon pink
7 to 8 um
Since before 1900, physicians and medical laboratory professionals counted RBCs in measured volumes to detect_____ or _____
anemia or polycythemia
means loss of oxygen-carrying capacity and is often reflected in a reduced RBC count or decreased RBC hemoglobin concentration
Anemia
means an increased RBC count reflecting increased circulating RBC mass, a condition that leads to hyperviscosity
Polycythemia
Historically, microscopists counted RBCs by carefully pipetting a tiny aliquot of whole blood and mixing it with_______
0.85% (normal) saline
Why is .85% normal saline solution mixed with RBCs?
Normal saline matches the osmolality of blood; consequently, the suspended RBCs retained their intrinsic morphology, neither swelling nor shrinking.
A______ dilution was typical for RBC counts, and a glass pipette designed to provide this dilution, the_____ pipette, was used routinely until the advent of automation.
1:200
Thoma pipette
The diluted blood was transferred to a glass counting chamber called a_____
hemacytometer