hemacytometer Flashcards
primarily used to count the cellular elements of the blood, including RBCs, WBCs, and platelets.
hemacytometer
the counting chamber used in the hemacytometer for manual counting is the __________
Improved Neubauer
elements in a hemacytometer kit
counting chamber, RBC pipette, WBC pipette, accessories (thick cover slip & suction device)
Odd One Out: Part of the hemacytometer kit
RBC pipette
Thick coverslip
Hemoglobin meter
WBC pipette
hgb meter
purpose of the central secondary square in the improved Neubauer counting chamber
count RBCs
Select All That Apply: Assist in blood cell counting in hemacytometer kit
Thick coverslip
RBC pipette
Centrifuge
Suction device
WBC pipette
Thick coverslip, RBC pipette, Suction device, WBC pipette
Select All That Apply: Types of counting chambers used in blood cell counting
Improved Neubauer
Speirs-Levy
Thoma
Fuchs-Rosenthal
Bass-Jones
all
T/F The Improved Neubauer counting chamber is divided into parallel platforms with the central platform being 0.1 mm lower than the lateral platforms.
T
The ruling of the central platform in the Improved Neubauer counting chamber contains __________ primary square(s) measuring ______ (9 square mm).
1 ; 3 x 3 mm
Select All That Apply: Central secondary square in Improved Neubauer chamber
1 Contains 25 tertiary squares
2 Used for counting WBCs
3 The tertiary squares measure 0.2 x 0.2 mm
4 5 of the 25 tertiary squares are used for RBC counting
1,3,4
T/F central platform of the Improved Neubauer chamber is separated by a moat that prevents overflow between the platforms.
true
Sequence: Manual RBC count using Improved Neubauer chamber
1 Count RBCs in 5 of the 25 tertiary squares in the central secondary square.
2 Place a thick coverslip over the chamber.
3 Fill the chamber with diluted blood.
4 View under a microscope using appropriate magnification.
2 3 4 1
OOO: 4 corner secondary squares of the Improved Neubauer chamber
1 16 tertiary squares
2 0.25 x 0.25 mm square size
3 Used for RBC counting
4 Used for WBC counting
3 used for RBC counting
depth of the central platform of the Improved Neubauer counting chamber
0.1 mm
Each of the four corner secondary squares of the Improved Neubauer chamber contains __________ tertiary squares measuring ____ mm x ___ mm , which are used for __________ counting.
16, 0.25 x 0.25 mm, WBC
T/F Laboratory automation has eliminated the need for manual counting using a hemacytometer.
F - manual is still used when automation fails / for crosschecking
The thickness of the __________ used with the hemacytometer is important to ensure accurate measurements during blood cell counting.
cover slip
The central platform of the Improved Neubauer counting chamber contains __________ parallel platforms extending across the slide and separated by moats.
three
central platform of the Improved Neubauer chamber is subdivided by what feature
transverse groove (moat)
T/F There are two primary ruled areas in one counting chamber
T
OOO: Area routinely used for cell counting
1 WBC counting in the four corners of the primary square
2 RBC counting in the center of the secondary square
3 WBC Differential Counting in peripheral blood films
4 Platelet counting in four corner secondary squares
4 - platelets are counted in the central secondary square
RBC counting is performed by counting cells in __________ corners and the center of tertiary squares in the central secondary square.
four
Select All That Apply: Area of cell counting in the hemacytometer
1 The area for WBC counting is 4 mm²
2 Platelets are counted in the whole central secondary square
3 The area of RBC counting is 5/25 of a tertiary square
4 The total magnification for WBC counting is 400x
1,2,3
T/F For RBC and platelet counting, we use a high power objective with a total magnification of 400x
t
Odd One Out: Lenss used in cell counting
1 Low power objective for WBC counting (10x)
2 Oil immersion objective for WBC differential counting (100x)
3 High power objective for RBC counting (40x)
4 Low power objective for platelet counting (20x)
4 - platelets are counted using the high power objective (40x)
For WBC differential counting, we use the __________ objective with a total magnification of __________
Oil immersion, 1000x
Select All That Apply: Steps for counting cells in a hemacytometer
1 Use the inverted L rule for counting cells
2 Count the cells that touch the top and the right
3 Use the total magnification of 1000x for RBC counting
4 Avoid duplicating cells by following a consistent method
1,4
Cell type counted using a low power objective (10x): WBC
WBC
T/F When counting cells in a hemacytometer, we count all cells in sight, including those which touch the four borders of the square
F - count cells touching the top and left borders and exclude those touching the bottom and right borders
counting area for platelets in the hemacytometer
whole central secondary square (1 mm²)
T/F The major difference between the Neubauer and Improved Neubauer chambers lies in the number of tertiary squares in the central square.
T
The Neubauer central secondary square has __________ tertiary squares, whereas the improved Neubauer has __________ tertiary squares.
16, 25
size of each tertiary square in the Neubauer chamber
0.25 x 0.25 mm
OOO: Difference between the Neubauer and Improved Neubauer chambers
1 Central square size
2 Number of tertiary squares
3 Overall depth of the chamber
4 Quality of RBC counting
3 - di nmn nagbagago depth oa k
T/F Fuchs-Rosenthal counting chamber is primarily used for low cell counts such as eosinophil count and spinal fluid count
T
The Fuchs-Rosenthal chamber has a grid area of __________ and a depth of __________
4 mm x 4 mm, 0.2 mm
volume of one large square in the Fuchs-Rosenthal chamber
0.2 μL
Select All That Apply: Fuchs-Rosenthal chamber
1 It has 16 smaller squares in the central square
2 The depth is 0.1 mm
3 The complete counting chamber has a volume of 3.2 μL
4 Used for leukopenia blood specimen counts
1 3 4
T/F: In the Fuchs-Rosenthal counting chamber, to calculate the WBC count per μL, the total cell count is divided by 3.
T
how many sections in Speirs-Levy counting chamber
4 sections ( 2 each side)
Select All That Apply: Speirs-Levy counting chamber
1 It has 4 sections in total
2 Each section has 10 squares measuring 1 x 1 mm
3 It has a depth of 0.1 mm
4 commonly used for rbc counting
1, 2
*4 - pde nmn kaso most commonly sa bacteria nd other cells dw
the Speirs-Levy chamber’s depth is __________; each section contains __________ squares
0.2 mm, 10
Select All That Apply: Speirs-Levy counting chamber
1 4 sections in total
2 each section has 10 squares measuring 1 x 1 mm
3 depth of 0.1 mm
4 commonly used for RBC counting
1 2
OOO: Speirs-Levy chamber
1 2 horizontal rows of squares
2 4 sections
3 Central secondary square with 25 smaller squares
4 Total area of 10 square mm
3
The Speirs-Levy chamber has a total area of __________ square mm, while the Fuchs-Rosenthal chamber’s complete volume is __________ μL.
10, 3.2
T/F Fuchs-Rosenthal and Speirs-Levy counting chambers are both designed for routine high cell counts like RBC counting.
F - designed for low cell counts (eosinophils, leukopenia)
T/F: The Thoma pipette is primarily used for counting red blood cells (RBCs) and white blood cells (WBCs) in a blood sample.
T
T/F The Thoma pipette is used for dilution before performing a cell count
T
the thoma pipette consists of several parts including a bulb, stem, bore in the stem, and a ________ in the bulb
bead
usual dilution for a WBC count using a Thoma pipette
1:20
RBC pipette vs WBC pipette
Volume of bulb
Size of bore in stem
Calibration
Usual dilution
Color of bead
Volume of bulb (rbc - 100 units ; wbc 10 units)
Size of bore in stem (rbc -Smaller ; wbc - bigger)
Calibration (rbc - 0.5, 1.0, 101 ; wbc - 0.5, 1.0, 11)
Usual dilution (RBC - 1:200; WBC - 1:20)
Color of bead (RBC- red, WBC - white/colorless)
T/F In WBC counting, it is necessary to lyse the RBCs because they would obstruct the counting process.
T
For lysing RBCs in a WBC count, a ________ solution or a ________% acetic acid solution is used.
hypotonic, 3-5
Select All That Apply: Thoma pipettes
1 The RBC pipette bulb volume is 100 units
2 The WBC pipette is used for immediate processing without lysing
3 The WBC pipette has a larger bore than the RBC pipette
4 The calibration for the RBC pipette includes 0.5, 1.0, and 101
1 3 4
Select All That Apply: Thoma pipettes
1The RBC pipette has a smaller bore than the WBC pipette
2 The WBC pipette uses isotonic solution for dilution
3 The bulb of the RBC pipette holds 100 units
4 The WBC pipette is designed to lyse RBCs for counting
1 3 4
volume of the bulb in a WBC Thoma pipette
10 units
When aspirating blood into the Thoma pipette, it is important to mix it slightly until __________
the bulb is filled
T/F In RBC counting with a Thoma pipette, there is no need for lysing the RBCs, and processing can be done immediately.
T
T/F Thoma pipette is used for dilution before performing a cell count.
T
T/F The stem of both the RBC and WBC Thoma pipettes is equivalent to 1 unit.
T
The usual dilution for the RBC Thoma pipette is __________, while for the WBC Thoma pipette it is __________
1:200, 1:20
T/F isotonic solution like NSS should be used in the RBC count to prevent lysis of red blood cells.
T
The WBC pipette uses a hypotonic solution, such as __________, to lyse the RBCs.
acetic acid
How long should the RBCs be lysed in the WBC count?
10 mins
Select All That Apply: Thoma pipette
1 The RBC pipette can be used for WBC counting.
2 The WBC pipette can be used for RBC counting.
3 The dilution should be exact for accurate counting.
4 The Thoma pipette is not suitable for cell counts.
1 2 3
T/F Disposable counting chambers such as Neubauer can use ordinary coverslips.
F - thick coverslips are needed
The ordinary coverslip cannot be used because it has an _________ surface.
uneven
purpose of omitting the first 5-6 drops when using the RBC pipette
remove diluent from the stem
T/F The Thoma pipette can be used for both RBC and WBC counting, with specific dilutions depending on the situation.
T
If blood is aspirated at the 0.5 mark of the RBC pipette, what is the dilution factor?`
1:200
If you aspirate blood at the 0.1 mark of the WBC pipette, what is the dilution?
1:1000
T/F When performing dilutions using the Thoma pipette, the stem is included in the dilution calculation.
F
Select All That Apply:
Diluting fluids used to prevent rouleaux formation
A. Formal citrate
B. Gowers solution
C. Isotonic saline
D. Hypertonic solution
A B C
