Blood Cells
Dr. Amam Ali Amam
PhD: Periodontal Disease
Blood Cells consists of
1- The cells
2- fluid
Blood flow within the closed circulatory system.
The blood is a special connective tissue (fluid).
( 5.5 Liter in a man)
Different blood cells
Fluid medium – Plasma
Plasma proteins + inorganic salts
Blood Cells, Functions:
1- Transport of Gases (O2, CO2).
2- Transports Nutrients from their site of absorption
to various areas of organs
3- Transports cells and hormones
4- Metabolic waste products cells and hormones
Blood cell types
1- Red blood cells - ERYTHROCYTES
(transport of oxygen and carbon dioxide)
2- White blood cells - LEUKOCYTES:
defense and immune systems
3- Platelets - THROMBOCYTES
control of bleeding ( haemostasis )
The clot blood contains:
1- Formed Elements
2- Serum
clear yellow liquid
1- The lower layer represents 42-47% of the entire volume
of blood in the hematocrit tube.
(It is Red and is made up of Erythrocytes )
2- The layer immediately above (1 % of blood volume),
which is white or grayish in color,
is called buffy coat and consists of Leukocytes.
Composition of Plasma
1-Substances of low or high molecular weight that make
up 10% of its volume.
2- The main plasma proteins are (7% of the volume):
albumin , globulins (α,β,γ), lipoproteins ,
prothrombin and fibrinogen (that participate in blood
coagulation ).
Albumin: the most abundant component, has a
fundamental role in maintaining the osmotic pressure
of the blood.
3- The remainder of the 10% consists of several organic
compounds (eg, amino acids, vitamins, hormones,
lipoproteins of various origins).
Methods of studying & staining
- Smear for blood , aspirate for bone marrow.
- Giemsa , Wright’s or Leishman’s method.
Erythrocytes
• biconcave disc shape without nuclei or
cytoplasmic organelles
• diameter 7.2 µm, 0.8 µm in diameter.
• Concen : ♂ 4.1 – 6 million \ mm3 ♀ 3,9 – 5.5 million \ mm3
• lifespan: 120 days .
95% haemoglobin
Haemo = porphyrine + Fe
Globin : α β γ δ
Haemoglobin - ♂ 15 – 18 g\100 ml, ♀ 14,5 g\100 m
Leukocytes
are divided into 2 groups:s
1- Granulocytes
2- Agranulocytes
Polymorphonuclear
Leukocytes
Mononuclear
Leukocytes
Neutrophils
Lymphocytes
Eosinophils
Monocytes
Basophils
Granulocytes
• cytoplasmic secretory granules
• single multilobed nucleus
• polymorphonuclear leukocytes or polymorph
Neutrophils
(Polymorphonuclear Leukocytes)
constitute 60-70% of circulating leukocytes.
diameter : 12-15 µm (in blood smears),
A nucleus: consisting of 2 to 5 (usually three)
lobes linked by fine threads of chromatin .
Function: Phagocytosis of bacteria.
short-lived cells with a half-life of 6-7 h in blood
and a life span of 1-4 days in connective tissues
Barr body ,visible in 3% of neutrophils of females
Eosinophils
(Polymorphonuclear Leukocytes)
Constituting only 2-4 % of leukocytes in normal blood.
Size: the same size of a neutrophil
diameter : 12-15 µm (in blood smears),
A nucleus: contains a characteristic bilobed nucleus.
a crystalline core.
Function: Defense against parasitic helminths,
Basophils
(Polymorphonuclear Leukocytes)
Less than 1 % of leukocytes in normal blood.
diameter : 12-15 µm (in blood smears),
The nucleus: is divided into irregular lobes.
Function: Release of histamine & other inflammation
mediators.
Main products: specific granules (0.5 µm in diameter)
containing histamine and heparin.
Lymphocytes
Less than 1 % of leukocytes in normal blood.
diameter : the small 6-8 µm
the large 18 µm
the small Lymphocytes has a spherical nucleus
The cytoplasma is scanty, it appears as a thin rim around
the nucleus.it has mitochondria and a small
Golgi complex
Function: Generate of antibody
Main products:Immunoglobulines.
Monocytes
Diameter: It’s the largest 12-20 µm
5 % of leukocytes in normal blood.
The nucleus is oval, horseshoe or kidney shaped.
: The cytoplasm is basophilic , containing very fine
azurophilic granules (lysosomes).
Golgi complex
Function: Generation of mononuclear-phagocyte system
cells in tissues,
phagocytosis and digestion of protozoa and virus and
senescent cells.
Main products: Granules with lysosomal enzymes
Platelets, (thrombocytes)
Diameter: It’s 2-4 µm.
platelet counts : 200,000 to 400,000 per microliter
of blood.
Life span : about 10 days.
Function: promote blood clotting and help repair
gaps
in the walls of blood vessels, preventing loss of
blood.
Central granular cytoplasm, Peripheral poorly
stained cytoplasm .
Main products: Blood-clotting factors.
Main functions: Clotting of blood.