3. Blood is a specialized bodily fluid (technically a tissue).
In vertebrates it is composed of blood cells suspended in a
liquid called blood plasma.
Plasma, which comprises 55% of blood fluid, is mostly
water (90% by volume), and contains dissolved proteins,
glucose, mineral ions, hormones, carbon dioxide (plasma
being the main medium for excretory product
transportation), platelets and blood cells themselves.
The blood cells present in blood are mainly red blood cells
(also called RBCs or erythrocytes) and white blood cells,
including leukocytes and platelets (also called
thrombocytes)
9. Formation of Blood Cells
Negative feedback systems regulate the
total number of RBCs and platelets in
circulation
Abundance of WBC types based of
response to invading pathogens or foreign
antigens
Hemopoiesis or hematopoiesis
Red bone marrow primary site
10. Red Blood Cells/ Erythrocytes
Contain oxygen-carrying protein hemoglobin
Production = destruction with at least 2
million new RBCs per second
Biconcave disc – increases surface area
Strong, flexible plasma membrane
Glycolipids in plasma membrane responsible
for ABO and Rh blood groups
Lack nucleus and other organelles
No mitochondria – doesn’t use oxygen
11. Hemoglobin
Globin – 4 polypeptide chains
Heme in each of 4 chains
Iron ion can combine reversibly with one oxygen
molecule
Also transports 23% of total carbon dioxide
Combines with amino acids of globin
Nitric oxide (NO) binds to hemoglobin
Releases NO causing vasodilation to improve blood flow
and oxygen delivery
13. Red Blood Cells
RBC life cycle
Live only about 120 days
Cannot synthesize new components – no nucleus
Ruptured red blood cells removed from circulation
and destroyed by fixed phagocytic macrophages
in spleen and liver
Breakdown products recycled
Globin’s amino acids reused
Iron reused
Non-iron heme ends as yellow pigment bilirubin and
biliverdin
15. Red blood cell
death and
phagocytosis
Key:
in blood
in bile
Macrophage in
spleen, liver, or
red bone marrow
1
Globin
Red blood cell
death and
phagocytosis
Key:
in blood
in bile
Macrophage in
spleen, liver, or
red bone marrow
Heme
2
1
Amino
acids
Reused for
protein synthesis
Globin
Red blood cell
death and
phagocytosis
Key:
in blood
in bile
Macrophage in
spleen, liver, or
red bone marrow
Heme
3
2
1
Amino
acids
Reused for
protein synthesis
Globin
Red blood cell
death and
phagocytosis
Transferrin
Fe3+
Key:
in blood
in bile
Macrophage in
spleen, liver, or
red bone marrow
Heme
4
3
2
1
Amino
acids
Reused for
protein synthesis
Globin
Red blood cell
death and
phagocytosis
Transferrin
Fe3+
Liver
Key:
in blood
in bile
Macrophage in
spleen, liver, or
red bone marrow
Ferritin
Heme
5
4
3
2
1
Amino
acids
Reused for
protein synthesis
Globin
Red blood cell
death and
phagocytosis
Transferrin
Fe3+
Fe3+ Transferrin
Liver
Key:
in blood
in bile
Macrophage in
spleen, liver, or
red bone marrow
Ferritin
Heme
6
5
4
3
2
1
Amino
acids
Reused for
protein synthesis
Globin
Red blood cell
death and
phagocytosis
Transferrin
Fe3+
Fe3+ Transferrin
Liver
+
Globin
+
Vitamin B12
+
Erythopoietin
Key:
in blood
in bile
Macrophage in
spleen, liver, or
red bone marrow
Ferritin
Heme Fe3+
7
6
5
4
3
2
1
Amino
acids
Reused for
protein synthesis
Globin
Circulation for about
120 days
Red blood cell
death and
phagocytosis
Transferrin
Fe3+
Fe3+ Transferrin
Liver
+
Globin
+
Vitamin B12
+
Erythopoietin
Key:
in blood
in bile
Erythropoiesis in
red bone marrow
Macrophage in
spleen, liver, or
red bone marrow
Ferritin
Heme Fe3+
8
7
6
5
4
3
2
1
Amino
acids
Reused for
protein synthesis
Globin
Circulation for about
120 days
Red blood cell
death and
phagocytosis
Transferrin
Fe3+
Fe3+ Transferrin
Liver
+
Globin
+
Vitamin B12
+
Erythopoietin
Key:
in blood
in bile
Erythropoiesis in
red bone marrow
Macrophage in
spleen, liver, or
red bone marrow
Ferritin
Heme
Biliverdin Bilirubin
Fe3+
9
8
7
6
5
4
3
2
1
Amino
acids
Reused for
protein synthesis
Globin
Circulation for about
120 days
Bilirubin
Red blood cell
death and
phagocytosis
Transferrin
Fe3+
Fe3+ Transferrin
Liver
+
Globin
+
Vitamin B12
+
Erythopoietin
Key:
in blood
in bile
Erythropoiesis in
red bone marrow
Macrophage in
spleen, liver, or
red bone marrow
Ferritin
Heme
Biliverdin Bilirubin
Fe3+
10
9
8
7
6
5
4
3
2
1
Amino
acids
Reused for
protein synthesis
Globin
Stercobilin
Bilirubin
Urobilinogen
Feces
Small
intestine
Circulation for about
120 days
Bacteria
Bilirubin
Red blood cell
death and
phagocytosis
Transferrin
Fe3+
Fe3+ Transferrin
Liver
+
Globin
+
Vitamin B12
+
Erythopoietin
Key:
in blood
in bile
Erythropoiesis in
red bone marrow
Macrophage in
spleen, liver, or
red bone marrow
Ferritin
Heme
Biliverdin Bilirubin
Fe3+
12
11
10
9
8
7
6
5
4
3
2
1
Amino
acids
Reused for
protein synthesis
Globin
Urine
Stercobilin
Bilirubin
Urobilinogen
Feces
Small
intestine
Circulation for about
120 days
Bacteria
Bilirubin
Red blood cell
death and
phagocytosis
Transferrin
Fe3+
Fe3+ Transferrin
Liver
+
Globin
+
Vitamin B12
+
Erythopoietin
Key:
in blood
in bile
Erythropoiesis in
red bone marrow
Kidney
Macrophage in
spleen, liver, or
red bone marrow
Ferritin
Urobilin
Heme
Biliverdin Bilirubin
Fe3+
13 12
11
10
9
8
7
6
5
4
3
2
1
Amino
acids
Reused for
protein synthesis
Globin
Urine
Stercobilin
Bilirubin
Urobilinogen
Feces
Large
intestine
Small
intestine
Circulation for about
120 days
Bacteria
Bilirubin
Red blood cell
death and
phagocytosis
Transferrin
Fe3+
Fe3+ Transferrin
Liver
+
Globin
+
Vitamin B12
+
Erythopoietin
Key:
in blood
in bile
Erythropoiesis in
red bone marrow
Kidney
Macrophage in
spleen, liver, or
red bone marrow
Ferritin
Urobilin
Heme
Biliverdin Bilirubin
Fe3+
14
13 12
11
10
9
8
7
6
5
4
3
2
1
16. Copyright 2009, John Wiley & Sons, Inc.
Anemia is defined as a below-normal plasma hemoglobin
concentration resulting from a decreased number of circulating red
blood cells or an abnormally low total hemoglobin content per unit
of blood volume
17. Copyright 2009, John Wiley & Sons, Inc.
Haematinics -Thesea re substancesr equired in the formation of blood,
and are used for treatment of anaemias.
Causes of anaemia-
(a) Blood loss (acute or chronic)
(b) Impaired red cell formation due to:
. Deficiency of essential factors, i.e. iron, vitamin B12folic acid.
erythropoietin deficiency.
18. Copyright 2009, John Wiley & Sons, Inc.
A. Iron
Iron is stored in intestinal mucosal cells as ferritin (an iron-protein
complex) until needed by the body.
Iron deficiency results from acute or chronic blood loss.
Supplementation with ferrous sulfate is required to correct the
deficiency.
B. Folic acid
The primary use of folic acid is in treating deficiency states that arise
from inadequate levels of the vitamin.
Folate deficiency may be caused by 1) increased demand (for
example, pregnancy and lactation), 2) poor absorption
caused by pathology of the small intestine, 3) alcoholism,
19. Copyright 2009, John Wiley & Sons, Inc.
C. Cyanocobalamin (vitamin B12)
Deficiencies of vitamin B12 can result from either low dietary levels
or, more commonly, poor absorption of the vitamin due to the failure
of gastric parietal cells to produce intrinsic factor (as in pernicious
anemia) or a loss of activity of the receptor needed for intestinal
uptake of the vitamin.
Erythropoietin normally made by the kidney, that regulates red
blood cell proliferation and differentiation in bone marrow.
Human erythropoietin, produced by recombinant DNA
technology, is effective in the treatment of anemia caused by end-
stage renal disease, anemia associated with
human immunodeficiency virus infection, and anemia in some
cancer patients. Darbepoetin
20. Erythropoiesis
Starts in red bone marrow
with proerythroblast
Cell near the end of
development ejects nucleus
and becomes a reticulocyte
Develop into mature RBC
within 1-2 days
Negative feedback
balances production with
destruction
Controlled condition is
amount of oxygen delivery
to tissues
Hypoxia stimulates release
of erythropoietin
21. White Blood Cells/ Leukocytes
Have nuclei
Do not contain hemoglobin
Granular or agranular based on staining
highlighting large conspicuous granules
Granular leukocytes
Neutrophils, eosinophils, basophils
Agranular leukocytes
Lymphocytes and monocytes
23. Functions of WBCs
Usually live a few days
Except for lymphocytes – live for months or years
Far less numerous than RBCs
Leukocytosis is a normal protective response to
invaders, strenuous exercise, anesthesia and
surgery
Leukopenia is never beneficial
General function to combat invaders by
phagocytosis or immune responses
24. Emigration of WBCs
Many WBCs leave the
bloodstream
Emigration (formerly
diapedesis)
Roll along endothelium
Stick to and then
squeeze between
endothelial cells
Precise signals vary for
different types of WBCs
25. WBCs
Neutrophils and macrophages are active
phagocytes
Attracted by chemotaxis
Neutrophils respond most quickly to tissue
damage by bacteria
Uses lysozymes, strong oxidants, defensins
Monocytes take longer to arrive but arrive in
larger numbers and destroy more microbes
Enlarge and differentiate into macrophages
26. WBCs
Basophils leave capillaries and release
granules containing heparin, histamine and
serotonin, at sites of inflammation
Intensify inflammatory reaction
Involved in hypersensitivity reactions (allergies)
Eosinophils leave capillaries and enter tissue
fluid
Release histaminase, phagocytize antigen-
antibody complexes and effective against certain
parasitic worms
27. Lymphocytes
Lymphocytes are the major soldiers of the
immune system
B cells – destroying bacteria and inactivating their
toxins
T cells – attack viruses, fungi, transplanted cells,
cancer cells and some bacteria
Natural Killer (NK) cells – attack a wide variety of
infectious microbes and certain tumor cells
28. Platelets/ Thrombocytes
Myeloid stem cells develop eventually into a
megakaryocyte
Splinters into 2000-3000 fragments
Each fragment enclosed in a piece of plasma
membrane
Disc-shaped with many vesicles but no nucleus
Help stop blood loss by forming platelet plug
Granules contain blood clot promoting chemicals
Short life span – 5-9 days
29. Stem cell transplants
Bone marrow transplant
Recipient's red bone marrow replaced entirely by healthy,
noncancerous cells to establish normal blood cell counts
Takes 2-3 weeks to begin producing enough WBCs to fight
off infections
Graft-versus-host-disease – transplanted red bone marrow
may produce T cells that attack host tissues
Cord-blood transplant
Stem cells obtained from umbilical cord shortly before birth
Easily collected and can be stored indefinitely
Less likely to cause graft-versus-host-disease
30. Hemostasis
Sequence of responses that stops bleeding
3 mechanisms reduce blood loss
1. Vascular spasm
Smooth muscle in artery or arteriole walls
contracts
2. Platelet plug formation
Platelets stick to parts of damaged blood vessel,
become activated and accumulate large
numbers
3. Blood clotting (coagulation)
32. 1
Red blood cell
Platelet
Collagen fibers
and damaged
endothelium
Platelet adhesion
1
1
2
Red blood cell
Platelet
Collagen fibers
and damaged
endothelium
Liberated ADP,
serotonin, and
thromboxane A2
Platelet adhesion
1
Platelet release reaction
2
1
2
3
Red blood cell
Platelet
Collagen fibers
and damaged
endothelium
Liberated ADP,
serotonin, and
thromboxane A2
Platelet plug
Platelet adhesion
1
Platelet release reaction
2
Platelet aggregation
3
33. Blood Clotting
3. Blood clotting
Serum is blood plasma
minus clotting proteins
Clotting – series of
chemical reactions
culminating in formation of
fibrin threads
Clotting (coagulation)
factors – Ca2+, several
inactive enzymes, various
molecules associated with
platelets or released by
damaged tissues
34. 3 Stages of Clotting
1. Extrinsic or intrinsic pathways lead to formation
of prothrombinase
2. Prothrombinase converts prothrombin into
thrombin
3. Thrombin converts fibrinogen (soluble) into fibrin
(insoluble) forming the threads of the clot
35. Tissue trauma
Tissue
factor
(TF)
Blood trauma
Damaged
endothelial cells
expose collagen
fibers
(a) Extrinsic pathway (b) Intrinsic pathway
Activated XII
Ca2+
Damaged
platelets
Ca2+
Platelet
phospholipids
Activated X
Activated
platelets
Activated X
PROTHROMBINASE
Ca2+
V
Ca2+
V
1
Tissue trauma
Tissue
factor
(TF)
Blood trauma
Damaged
endothelial cells
expose collagen
fibers
(a) Extrinsic pathway (b) Intrinsic pathway
Activated XII
Ca2+
Damaged
platelets
Ca2+
Platelet
phospholipids
Activated X
Activated
platelets
Activated X
PROTHROMBINASE
Ca2+
V
Ca2+
Prothrombin
(II)
Ca2+
THROMBIN
(c) Common
pathway
V
1
2
+
+
Tissue trauma
Tissue
factor
(TF)
Blood trauma
Damaged
endothelial cells
expose collagen
fibers
(a) Extrinsic pathway (b) Intrinsic pathway
Activated XII
Ca2+
Damaged
platelets
Ca2+
Platelet
phospholipids
Activated X
Activated
platelets
Activated X
PROTHROMBINASE
Ca2+
V
Ca2+
Prothrombin
(II)
Ca2+
THROMBIN
Ca2+
Loose fibrin
threads
STRENGTHENED
FIBRIN THREADS
Activated XIII
Fibrinogen
(I)
XIII
(c) Common
pathway
V
1
2
3
+
+
36. Blood Clotting
Extrinsic pathway
Fewer steps than intrinsic and occurs rapidly
Tissue factor (TF) or thromboplastin leaks into the blood
from cells outside (extrinsic to) blood vessels and initiates
formation of prothrombinase
Intrinsic pathway
More complex and slower than extrinsic
Activators are either in direct contact with blood or
contained within (intrinsic to) the blood
Outside tissue damage not needed
Also forms prothrombinase
37. Blood Clotting: Common pathway
Marked by formation of prothrombinase
Prothrombinase with Ca2+ catalyzes conversion of
prothrombin to thrombin
Thrombin with Ca2+ converts soluble fibrinogen
into insoluble fibrin
Thrombin has 2 positive feedback effects
Accelerates formation of prothrombinase
Thrombin activates platelets
Clot formation remains localized because fibrin absorbs
thrombin and clotting factor concentrations are low
38. Blood Groups and Blood Types
Agglutinogens – surface of RBCs contain
genetically determined assortment of
antigens
Blood group – based on presence or absence
of various antigens
At least 24 blood groups and more than 100
antigens
ABO and Rh
39. ABO Blood Group
Based on A and B antigens
Type A blood has only antigen A
Type B blood has only antigen B
Type AB blood has antigens A and B
Universal recipients – neither anti-A or anti-B antibodies
Type O blood has neither antigen
Universal donor
Reason for antibodies presence not clear
41. Hemolytic Disease
Rh blood group
People whose RBCs have
the Rh antigen are Rh+
People who lack the Rh
antigen are Rh-
Normally, blood plasma
does not contain anti-RH
antibodies
Hemolytic disease of the
newborn (HDN) – if blood
from Rh+ fetus contacts Rh-
mother during birth, anti-Rh
antibodies made
Affect is on second Rh+
baby
42. Typing Blood
Single drops of blood are
mixed with different
antisera
Agglutination with an
antisera indicates the
presence of that antigen
on the RBC