Blood sys

University of IshikFaculty of Dentistry2nd stage Lec. Physiology

Abdulqadir Kh. Hamad
Abdulqadir.bio@raparinuni.org

The Cardiovascular System: The Blood

Blood
• Transportation
• Gases, nutrients, hormones, waste products
• Regulation
• Regulation of pH and osmosis osmotic pressure
• Maintain of the body
• Protection
• Protection against foreign substances
• By white blood cells, immune proteins (Antibodies & Compete Protein )
• Clot formation prevent bleeding


Components of Blood
Blood plasma – water liquid extracellular matrix
90.5 % -91.5% water, 8.5% solutes (primarily proteins)
Hepatocytes synthesize most plasma proteins
Albumins, fibrinogen, antibodies
Other solutes include electrolytes, nutrients, enzymes, hormones, gases and waste products
Formed elements – cells and cell fragments
Erythrocytes: Red blood cells (RBCs) :
Leukocytes : White blood cells (WBCs)
Thrombocyte : Platelets

Components of Blood 1- Plasma

Liquid part of blood
Blood plasma – water liquid extracellular matrix
91.5% water, 8.5% solutes (primarily proteins)
Hepatocytes synthesize most plasma proteins
Albumins, fibrinogen, antibodies Colloid: Liquid containing suspended substances that don’t settle out
Albumin: Important in regulation of water movement between tissues and blood
Globulins: Immune system or transport molecules
Fibrinogen: Responsible for formation of blood clots
Other solutes include electrolytes, nutrients, enzymes, hormones, gases and waste products


II. Plasma
C. ~2% organic solutes
1. amino acids
2. vitamins
3. hormones
4. lipoproteins
D. ~1% inorganic salts
E. dissolved gases

Formed Elements of Blood

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


Red bone marrow primary site
Pluripotent stem cells have the ability to develop into many different types of cells

Formation of Blood Cells

Stem cells in bone marrow
Reproduce themselves
Proliferate and differentiate
Cells enter blood stream through sinusoids
Formed elements do not divide once they leave red bone marrow
Exception is lymphocytes

Formation of Blood Cells

Pluripotent stem cells produce
Myeloid stem cells
Give rise to red blood cells, platelets, monocytes, neutrophils, eosinophils and basophils
Lymphoid stem cells give rise to
Lymphocytes
Hemopoietic growth factors regulate differentiation and proliferation
Erythropoietin – RBCs
Thrombopoietin – platelets
Colony-stimulating factors (CSFs) and interleukins – WBCs


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

19-13

Erythrocytes
Structure
Biconcave, anucleate
Components
Hemoglobin
Lipids, ATP, carbonic anhydrase
Function
Transport oxygen from lungs to tissues and carbon dioxide from tissues to lungs




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

Shapes of RBC and Hemoglobin

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 urobilin in urine or brown pigment stercobilin in feces


Formation and Destruction of RBC’s

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


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

Copyright 2009, John Wiley & Sons, Inc.

19-21

Erythropoiesis
Production of red blood cells
Stem cells proerythroblasts early erythroblasts intermediate late reticulocytes
Erythropoietin: Hormone to stimulate RBC production

Iron Metabolism: Key to Hemoglobin O2 Transport

19-23

Hemoglobin Breakdown

Copyright 2009, John Wiley & Sons, Inc.