experiment to count the number of RBC in HUMAN BLOOD

1. RED BLOOD CELLS(RBC)
ENUMERATION
BASIL K VARGHESE
14BCB0002
VIT University

2. INTRODUCTION
• Red blood cells make up almost 45 % of the blood volume.
• Their primary function is to carry oxygen from the lungs to every cell in the body.
• Red blood cells are composed predominantly of a protein and iron compound,
called hemoglobin, that captures oxygen molecules as the blood moves through the
lungs, giving blood its red color.
• As blood passes through body tissues, hemoglobin then releases the oxygen to cells
throughout the body.
• Red blood cells are so packed with hemoglobin that they lack many components,
including a nucleus, found in other cells.

3. ERYTHROCYTE COUNT
• Is the number of erythrocytes per micro litter of blood.
• Normal Ranges:
• Male 4.2 – 5.4 106/µL
• Female 3.6 – 5.0 106/µL
• New born 5.5 – 6.5 106/µL
• Erythrocyte count increased in case of polycythemia and decreased in anemia.

4. PRINCIPLE
• In order to facilitate RBCs count a specified volume of blood is diluted with a
specified volume of isotonic fluid.
• Red cell diluting fluid must be:
• anti-coagulant anti-hemolysis.
• anti-aggregation.
• anti-Rouleaux.
• preserve RBC shape.

5. • Hemocytometer

6. MATERIALS REQUIRED
• Drop of Blood(diluted)
• Glass slide and coverslip
• Hemocytometer
• Compound Microscope

7. PROCEDURE
1.Dilute the blood sample
2.Load the hemocytometer

8. Focus with 10x objective lens
on the large central square.
This square is ruled into 25
small squares, each of which
is further divided into 16
smaller squares, of the 25
squares, only the four corner
squares, and one middle
square are used to count
RBCs. Count for all 5 square
and take average(N)

9. • If cells are touching the 4 perimeter sides of a corner square, only
count cells on 2 sides, either the 2 outer sides or 2 inner sides.

10. CALCULATIONS
• Total RBC Count= (N X 20 X20 X 10)/16
• N=Avg. of blood cells counted in all 5 squares