blood cell and constituents

1. BLOOD
Submitted by : Aswin M B

2. WHAT IS BLOOD?
Blood is a body fluid in humans and other animals that delivers necessary substances
such as nutrients and oxygen to the cells and transports metabolic waste products away
from those same cells. In vertebrates, it is composed of blood cells suspended in blood
plasma.

3. HAEMATOLOGY
• The branch of science concerned with the study of blood, blood-forming tissues and
the disorders associated with them is called Haematology.
Greek: (Haeme-blood; logos-study)
• The blood is a special type of fluid connective tissue derived from mesoderm.

4. PROPERTIES OF BLOOD
Colour Bright red in arteries & dark red in veins
Mass 8% of the body mass
pH Slightly alkaline (pH = 7.35 – 7.45)
Taste Salty (Mean salinity = 0.85% mainly NaCl)
Temperature 38°C (100.4°F)
Viscosity
(relative to H2O)
Whole blood = 4.5 – 5.5
Plasma = 2.0
Volume 5 – 6 litre
Osmolarity 280 – 300 mOsm/L

5. COMPOSITION OF BLOOD

6. BLOOD
PLASMA
(55%)
Cellular elements
(45%)
RBCs
(Erythrocytes)
WBCs
(Leucocytes)
Platelets
(Thrombocytes)

7. PLASMA
• Plasma is a pale yellow coloured liquid component of a blood
that holds the cellular elements of blood in suspension.

8. Plasma
Water
(91.5%)
Proteins
(7%)
Other solutes
(1.5%)
Albumins Globulins Fibrinogen
Waste products
(Urea, uric acid, ammonia,
creatinine)
Gases
(O2, CO2, N2)
Nutrients
(Glucose, amino acid, fatty acids)
Electrolytic ions
(Na+, K+, Mg2+, Ca2+, SO₄²-,
HCO3− )

9. • HCO3

10. RED BLOOD CELLS
Shape
Circular biconcave non-nucleated
Size Diameter = 7 – 8µm
Thickness = 2.5µm
Count Adult male = 5.4 million RBCs/µl
Adult female = 4.8 million RBCs/µl
Life span
120 days
Production Adult – Red bone marrow of lung bones
Child(up to 5) – Bone marrow of all the bones
Fetus - Liver & spleen

11. • Biconcave disc shape, which is suited for the
gas exchange. The shape is flexible so that RBCs
can pass though the smallest blood vessels, i.e.,
capillaries.
• Increased no. of RBC – Polycythemia
• Decreased no. of RBC - Erythropenia
* Erythrocytes are smaller than Leukocytes.
*No nucleus nor mitochondria

12. HAEMATOCRIT/PACKED CELL VOLUME
• Packed cell volume is the ratio of the volume of erythrocytes to that of whole blood. It is
expressed in percentage.
• Anticoagulants used for PCV estimation
1. Heparin
2. EDTA
3. Double oxalate (ammonium and potassium oxalates)
Normal value
Male – 42 – 52%
Female – 37 – 47%

14. HAEMOGLOBIN
• Haemoglobin (Hb) is the red blood pigment, exclusively found in erythrocytes (Greek:
erythrose—red; kytos—a hollow vessel).
• Haemoglobin, an allosteric protein, consists of four protein (globin) chains, to each of
which is attached a haem moiety, an iron-porphyrin compound. Two pairs of globin
chains exist within each haemoglobin molecule.
• Normal concentration of Hb in blood
Male = 14 – 16 g/dl
Female = 15 – 16 g/dl

15. STRUCTURE OF HAEMOGLOBIN
• Haemoglobin (mol. wt. 64,450) is a conjugated protein, containing globin—the
apoprotein part—and the haeme—the non-protein part (prosthetic group).
Haemoglobin is a tetrameric allosteric protein.
• One molecule of hemoglobin (with four hemes) can bind
with four molecules of O2. This is in contrast to myoglobin
(with one heme) which can bind with only one molecule
of oxygen.

16. STRUCTURE OF GLOBIN
• Globin consists of four polypeptide chains of two different primary structures
(monomeric units).
• The common form of adult hemoglobin (HbA1) is made up of two α-chains and two ß-
chains (α2ß2). Some authors consider hemoglobin consisting of two identical dimers—
(αß)1 and (αß)2. Each α-chain contains 141 amino acids while ß-chain contains 146
amino acids. Thus HbA1 has a total of 574 amino acid residues.

17. STRUCTURE OF HEME
• The characteristic red colour of hemoglobin (ultimately blood) is due to heme.
• Heme contains a porphyrin molecule namely protoporphyrin IX, with iron at its center.
Protoporphyrin IX consists of four pyrrole rings to which four methyl, two propionyl and
two vinyl groups are attached.
Protoporphyrin IX Formula : C34H34N4O4

18. WHITE BLOOD CELLS
Shape Amoeboid nucleated
Size 12 – 15µm
Colour Colourless & translucent
Count 5000 – 10000 WBCs/µL
Life span 10 – 13 days
production Adult – Liver, spleen, tonsils, bone
marrow
Foetus – Liver, spleen

19. • Increase in number of WBCs is known as leucocytosis.
• Decrease in number of WBCs is known as leucopenia.
• Pathological increase in number of WBCs is known as leukemia (blood cancer).
Functions
1. Defense against pathogens.
2. Removal of toxins, wastes & damaged cells

20. TYPES OF WBC
• Granulocytes
These WBC have granules in their cytoplasm.
example : Neutrophils, eosinophils, basophils
• Agranulocytes
These are without granules in their cytoplasm.
example : Monocytes, lymphocytes

22. WBC PROPERTIES FUNCTION PRODUCTION
NEUTROPHILS Nucleus with 3- 4 lobes.
Stain with acidic dye
(hematoxylin).
Destroy bacteria by
phagocytosis.
Bone marrow
EOSINOPHILS Nucleus with 2 lobes.
Stain with acidic dye
(eosin).
Compact the effect of
histamine in allergic
reactions.
Bone marrow
BASOPHILS Nucleus with indistinct
lobes.
Stain with basic dye
(methylene blue).
Liberate heparin &
histamine in allergic
reactions to intensify
inflammatory response.
Bone marrow

23. LYMPHOCYTES Smallest of WBCs.
Large round
nucleus.
Produce antibiotics. Bone marrow,
spleen, tonsils
MONOCYTES Largest of WBCs.
Large kidney shaped
nucleus.
Ingest
microorganism.
Bone marrow

24. PLATELETS
Shape Circular biconvex non-nucleated
Size 2 – 4µm
Count 1,50,000 – 4,00,000 platelets/µL
Life span 5 – 9 days
Function Blood clotting

25. THROMBOPOIESIS
• Increase in number of platelets is known as thrombocytosis.
• Decrease in number of platelets is known as thrombocytopenia.
Platelets are the fragments of large cells called megakaryocytes
that remain in the bone marrow.

26. BLOOD CLOTTING
Blood clotting is the process in which blood looses its fluidity and becomes a
jelly like mass few minutes after it is shed out.

28. HEMATOPOIESIS
Hematopoiesis is the production of all of the cellular components of blood and blood
plasma.
All cellular blood components are derived from haematopoietic stem cells.
In a healthy adult person, approximately 1011–1012 new blood cells are produced
daily in order to maintain steady state levels in the peripheral circulation.