, Dr. Vivek V. Nalgirkar
Professor (Physiology)
D.Y. Patil University, School of Medicine, Nerul, Navi Mumbai
BLOOD
Introduction
SECTION 1: Plasma proteins: Function, Clinical significance
SECTION 2: Erythrocytes: Introduction, Erythropoiesis: Steps in erythropoiesis, factors
influencing erythropoiesis; Anemia
SECTION 3: White blood cells (WBCs): Classification, Functions, Immunity
SECTION 4: HEMOSTASIS - Platelets, Coagulation, anticoagulants, bleeding and clotting
disorders
SECTION 5: Blood groups: Blood group systems (ABO & Rh), hemolytic disease of
newborn, blood transfusion
-1-
, Introduction
Blood is a liquid connective tissue. It is a component of the extracellular
fluid (ECF). It circulates throughout the body within blood vessels. It is
red in colour due to presence of haemoglobin inside red blood cells.
pH of blood ~ 7.4.
Specific gravity ~ 1.060
Total blood volume in body ~ approx. 5 L or 8% of body weight.
Two components of blood are:
(A) Liquid component – called plasma (55%), and
(B) Cells – 45% (also called “formed elements of blood”).
{It should be understood clearly, that any unit quantity of blood will
have 45% cells and 55% plasma.}
Specific gravity of whole blood = 1.060; Specific gravity of plasma =
1.030 and Specific gravity of cells = 1.090.
Viscosity: Relative viscosities of water, plasma, and whole blood are 1,
3, and 5, respectively. Absolute viscosity is measured in poise.
Blood cells (or formed elements) are of 3 types:
1. Red blood cells (RBCs or erythrocytes) – 4.5 to 6 million/mm3 of blood.
Their main function is transport O2 and CO2 in blood. Apart from that,
they also play a role in body’s acid-base balance.
2. White blood cells (WBCs or leucocytes) – 4000 to 11000/mm3 of blood.
They are concerned with body’s defence mechanisms and immunity.
3. Platelets (or thrombocytes) – 1.5 to 4 lacs/mm3 of blood. They perform a
function of stoppage of bleeding after a blood vessel is ruptured.
The plasma component of blood is mainly composed of water (91%).
Other substances in plasma:
Inorganic substances – Na+, K+, Ca++, Cl-, iron, copper, etc.
Organic substances – proteins, lipids, glucose, other nutrients, hormones, etc.
Video link: Specific gravity of blood and its importance
-2-
, SECTION 1
Plasma proteins
- Proteins present in plasma.
- Normal level – 6 to 8 gm%
- 3 major plasma proteins are – albumin (4.5 to 5.5 gm%), globulins,
(1.5 to 2.5 gm%), fibrinogen (0.2 to 0.4 gm%).
Albumin : globulin ratio (A:G) = 1.7: 1 (up to 2:1)
1. Albumin –
- Synthesized in the liver.
- Performs two important functions: (i) exerts colloid osmotic
pressure of the plasma, (ii) transports various substances
(bilirubin, hormones, etc.)
2. Globulins –
- 3 types: , , and
- Alpha and beta globulins transport various substances in plasma.
- Gamma-globulins are immunoglobulins. They are formed from a
WBC called B-lymphocyte.
3. Fibrinogen –
- Synthesized in the liver.
- It converts into fibrin, to form a blood clot. This happens when a
blood vessel is ruptured.
Functions of plasma proteins:
(1) Colloid osmotic pressure –
Plasma proteins (mainly albumin) exert this pressure.
It is about 25-27 mm Hg.
It is a pressure that pulls water into the blood capillaries by osmosis.
(2) Viscosity of blood –
Viscosity of whole blood is about 5 times that of water. Viscosity of
plasma is 3 times that of water. Plasma viscosity is exerted by plasma
proteins.
(3) Transport of substances –
- Albumin transports various endogenous & exogenous substances.
E.g. hormones, bilirubuin, drugs.
- Globulins also perform the function of transport. E.g. haptoglobin
transport haemoglobin (Hb) when Hb is outside RBCs in the
-3-
Professor (Physiology)
D.Y. Patil University, School of Medicine, Nerul, Navi Mumbai
BLOOD
Introduction
SECTION 1: Plasma proteins: Function, Clinical significance
SECTION 2: Erythrocytes: Introduction, Erythropoiesis: Steps in erythropoiesis, factors
influencing erythropoiesis; Anemia
SECTION 3: White blood cells (WBCs): Classification, Functions, Immunity
SECTION 4: HEMOSTASIS - Platelets, Coagulation, anticoagulants, bleeding and clotting
disorders
SECTION 5: Blood groups: Blood group systems (ABO & Rh), hemolytic disease of
newborn, blood transfusion
-1-
, Introduction
Blood is a liquid connective tissue. It is a component of the extracellular
fluid (ECF). It circulates throughout the body within blood vessels. It is
red in colour due to presence of haemoglobin inside red blood cells.
pH of blood ~ 7.4.
Specific gravity ~ 1.060
Total blood volume in body ~ approx. 5 L or 8% of body weight.
Two components of blood are:
(A) Liquid component – called plasma (55%), and
(B) Cells – 45% (also called “formed elements of blood”).
{It should be understood clearly, that any unit quantity of blood will
have 45% cells and 55% plasma.}
Specific gravity of whole blood = 1.060; Specific gravity of plasma =
1.030 and Specific gravity of cells = 1.090.
Viscosity: Relative viscosities of water, plasma, and whole blood are 1,
3, and 5, respectively. Absolute viscosity is measured in poise.
Blood cells (or formed elements) are of 3 types:
1. Red blood cells (RBCs or erythrocytes) – 4.5 to 6 million/mm3 of blood.
Their main function is transport O2 and CO2 in blood. Apart from that,
they also play a role in body’s acid-base balance.
2. White blood cells (WBCs or leucocytes) – 4000 to 11000/mm3 of blood.
They are concerned with body’s defence mechanisms and immunity.
3. Platelets (or thrombocytes) – 1.5 to 4 lacs/mm3 of blood. They perform a
function of stoppage of bleeding after a blood vessel is ruptured.
The plasma component of blood is mainly composed of water (91%).
Other substances in plasma:
Inorganic substances – Na+, K+, Ca++, Cl-, iron, copper, etc.
Organic substances – proteins, lipids, glucose, other nutrients, hormones, etc.
Video link: Specific gravity of blood and its importance
-2-
, SECTION 1
Plasma proteins
- Proteins present in plasma.
- Normal level – 6 to 8 gm%
- 3 major plasma proteins are – albumin (4.5 to 5.5 gm%), globulins,
(1.5 to 2.5 gm%), fibrinogen (0.2 to 0.4 gm%).
Albumin : globulin ratio (A:G) = 1.7: 1 (up to 2:1)
1. Albumin –
- Synthesized in the liver.
- Performs two important functions: (i) exerts colloid osmotic
pressure of the plasma, (ii) transports various substances
(bilirubin, hormones, etc.)
2. Globulins –
- 3 types: , , and
- Alpha and beta globulins transport various substances in plasma.
- Gamma-globulins are immunoglobulins. They are formed from a
WBC called B-lymphocyte.
3. Fibrinogen –
- Synthesized in the liver.
- It converts into fibrin, to form a blood clot. This happens when a
blood vessel is ruptured.
Functions of plasma proteins:
(1) Colloid osmotic pressure –
Plasma proteins (mainly albumin) exert this pressure.
It is about 25-27 mm Hg.
It is a pressure that pulls water into the blood capillaries by osmosis.
(2) Viscosity of blood –
Viscosity of whole blood is about 5 times that of water. Viscosity of
plasma is 3 times that of water. Plasma viscosity is exerted by plasma
proteins.
(3) Transport of substances –
- Albumin transports various endogenous & exogenous substances.
E.g. hormones, bilirubuin, drugs.
- Globulins also perform the function of transport. E.g. haptoglobin
transport haemoglobin (Hb) when Hb is outside RBCs in the
-3-
