2. Blood
• Blood is a connective tissue
• Its volume is 5-6 L in males
and 4-5 L in females
• It is slightly alkaline, with a pH of ~ 7.4
• Its color varies from bright to dark red
• It has a salty metallic taste
• It is considered as the ‘fluid of life’ because it carries
oxygen from lungs to all parts of the body and carbon
dioxide from all parts of the body to the lungs.
• Also called fluid of growth as will as fluid of health.
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3. PROPERTIES OF BLOOD
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1:Color: Blood is red in color.
• Arterial blood: scarlet red because it contains
more oxygen.
• Venous blood: purple red because of more carbon
dioxide.
2. Blood volume
» 70 mL/kg of body weight
» 5 - 6 liters in males
» 4 - 5 liters in females
» newborn baby:450 ml.
• It is about 8% of the body weight in a normal
young healthy adult.
4. Conti…
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3.Temperature - 100.40F
4. pH - 7.35 to 7.45
5. Specific gravity:
• Specific gravity of total blood :
• Specific gravity blood cells :
• Specific gravity of plasma :
1.052 to 1.061
1.092 to 1.101
1.022 to 1.026
6. Viscosity: Blood is five times more viscous than water.
It is mainly due to red blood cells and plasma proteins.
5. Functions of blood
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Blood have four major functions
1. Transportation
2. Regulation
3. Protection
4. Storage
6. Functions of blood
1. Transportation
• Respiratory
Red blood cells or erythrocytes
transport Oxygen from lungs to
cells and Carbon dioxide from
cells to lungs
• Nutritive
Blood absorb nutrients from
digested foods in GIT and
transport to all the cells in body
• Excretory
Metabolic wastes, excess water and ions , and other molecules not
needed by the body are carried by the blood to the kidneys and
excreted in the urine
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7. Functions of blood
• 2. Regulation
regulate body temperature
regulate pH through buffers
Hormonal
Enzymes
Water
Acid base balance
3. Storage Function :
Water and some important substances like proteins, glucose,
sodium and potassium are constantly required by the tissues.
Blood serves as a readymade source for these substances.
4. Protection
Through hemostasis & immune response.
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8. COMPOSITION OF BLOOD
• Blood contains the blood cells which are called
formed elements and the liquid portion
known as plasma.
• The formed elements or cellular part is 45%.
• The plasma part is 55%
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10. Formed Elements of Blood
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• Red blood cells (R.B.C.)
• White blood cells (W.B.C.)
granular leukocytes
neutrophils
eosinophils
basophils
agranular leukocytes
lymphocytes - T cells, B cells, natural killer cells (N.K.C)
monocytes
• Platelets (special cell fragments)
11. Major portion of blood
Plasma
• Straw colored clear liquid
• Contains 90% water
• 7% plasma proteins
created in liver
confined to bloodstream
albumin
maintain blood osmotic
pressure
immunoglobulins
antibodies bind to foreign
substances called antigens
form antigen-antibody
complexes
fibrinogen
for clotting
• 2% other substances
Serum
• clear straw-colored fluid
that oozes from blood clot
• Volume of the serum is
almost the same as that of
plasma (55%).
• Serum = Plasma –Fibrinogen
• Plasma without clotting factors is
called “serum”
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hormones, waste products
12. Function of plasma proteins
1. Coagulation of blood – Fibrinogen to fibrin
2. Defense mechanism of blood – Immunoglobulins
3. Transport mechanism – α Albumin, β globulin transport hormones, gases,
enzymes, etc.
4. Maintenance of osmotic pressure in blood
5. Acid-base balance
6. Provides viscosity to blood
7. Provides suspension stability of RBC
8. Reserve proteins
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13. • Originate in the bone marrow
• Resemble the shape of a doughnut without a hole (biconcave)
• Average lifespan is 120 days
• Normal value = approximately 4 to 5.5 million per cubic
millimeter of blood
• Contains an iron-rich protein molecule called hemoglobin
• Responsible for carrying oxygen and removing carbon dioxide
from every body cell
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14. Conti…
• Normal hemoglobin level
• Male = 14–18 grams/100 mL of blood
• Female = 12–16 grams/100 mL of blood
• Responsible for carrying oxygen and removing carbon dioxide
from every body cell
• An abnormally low hemoglobin level and/or decrease in the
number of red blood cells is called anemia.
• Symptoms of anemia
1. Weakness
2. Headache
3. Pale skin color
4. Difficulty breathing
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15. • Also known as white blood cells
• Primarily responsible for
destroying foreign substances
such as pathogens
• Appear round and white because they lack hemoglobin
• Normal adult has 4,000 to 11,000 white blood cells per cubic
millimeter of blood
• Types of White Blood Cells
Granulocytes
Agranulocytes
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17. Granulocytes
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Neutrophils
Normal value is 1.5 to 8.0 (1,500 to 8,000/mm3).
1. First line of defense against invading micro-organisms.
2. Powerful and effective killer machine – contains
enzymes like protease, elastase, metalloproteinase,
NADPH oxidase; antibody like substances called
defensins.
– Defensins – antimicrobial peptides active against
bacteria and fungi.
• 3.Secrete Platelet Aggregation Factor (PAF) –
accelerates the aggregation of platelet during injury to
the blood vessels
18. Granulocytes
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Eosinophils
Normal levels of eosinophils vary between 0% and 4%, which is under 350
cells per micro-liter of blood.
Secrete lethal substances at the time of exposure to foreign
proteins/parasites
1. Eosinophill peroxidase – detroy worms, bacteria and tumor cells.
2. Major basic protein – damage parasites
3. Eosinophill cationic protein (ECP)- destroys helminths.
4. Eosinophill derived neurotoxin – destroys nerve fibres (myelinated nerve
fibres)
19. Granulocytes
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Basophils
Approximately 0.4% to 1% of white blood cells are basophils.
• Basophill granules release some important substances like –
1. Histamine – Acute hypersensitivity reaction- vascular changes, increase capillary
permeability
2. Heparin – prevents intravascular blood clotting
3. Hyaluronic acid – necessary for deposition of ground substances in basement
membrane
4. Proteases – exaggerate inflammation
• Basophill have IgE receptor – hypersensitivity reaction
20. Agranulocytes
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Monocytes
• Largest in size of all the
white blood cells
• Primary function is
phagocytosis
• Survive for several months
• Effective against chronic
infections
Lymphocytes
• Assist with the immune
system
• Produce antibodies that
destroy pathogens
• Aid in controlling allergic
reactions
22. (Platelets)
A normal platelet count ranges from 150,000 to 450,000 platelets per
microliter of blood.
Having more than 450,000 platelets is a condition called thrombocytosis.
having less than 150,000 is known as thrombocytopenia.
1. Blood clotting
2. Clot retraction
3. Defense mechanism
4. Homeostasis
5. Repair and rupture
of blood vessel
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23. Hematocrit (Hct) Levels
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Hematocrit Value:
This is the ratio of the volume of red cells to the volume
of whole blood
anticoagulated blood in hematocrit tube centrifuge at
3000rpm for 30 min .
Blood cell settle down in bottom and plasma remain on
the top .
45% cellular part and 55% plasma part
This red blood cells value express in percentage is
called hematocrit value or packed cell volume (PCV)
