Transcript Blood - TeacherWeb

10
Blood
PowerPoint® Lecture Slide Presentation by Jerry L. Cook, Sam Houston University
ESSENTIALS
OF HUMAN
ANATOMY
& PHYSIOLOGY
EIGHTH EDITION
ELAINE N. MARIEB
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Blood
Blood
 The only fluid tissue in the human body
 Connective tissue: living cells & non-living matrix
 Oxygen-rich blood is scarlet red
 Oxygen-poor blood is dull red, violet, blue
 pH must remain between 7.35–7.45
 Composed of approximately 90 percent water, and
dissolved substances: Nutrients, Salts (metal ions),
Respiratory gases (CO2, O2), Hormones, Proteins,
Waste products
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Plasma Proteins
Proteins found in blood plasma (fluid part of blood)
 Albumin – regulates osmotic pressure
 Clotting proteins – help to stem blood loss when
a blood vessel is injured
 Antibodies – help protect the body from antigens
Living cells found in blood
 Erythrocytes = red blood cells (RBCs)
 Leukocytes = white blood cells (WBCs)
 Platelets = cell fragments
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Erythrocytes (Red Blood Cells)
Erythrocytes (RBCs)
 The main function is to carry oxygen
 Donut biconcave disk shape
 Contain hemoglobin (iron containing protein)
that binds to oxygen
 Anucleate (no nucleus)
 Outnumber white blood cells 1000:1
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Leukocytes (White Blood Cells)
Leukocytes (WBCs)
 Crucial in the body’s defense against disease
 Have nucleus; can move by ameboid motion
 Respond to chemicals released by damaged tissues
 Normal levels: 4,000 and 11,000 cells per ml
 Abnormal leukocyte levels:
 Leukocytosis: Above 11,000 leukocytes/ml
 Generally indicates an infection
 Leukopenia: Abnormally low leukocyte level
 Commonly caused by certain drugs
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Types of Leukocytes
Types of Leukocytes
 Granulocytes
 Neutrophils: phagocytes (ungulf) infectious
cells, materials
 Eosinophils: respond to allergies, parasites
 Basophils: have histamine, cause inflammation
 Agranulocytes
 Lymphocytes: important in immune response
 Monocytes: largest WBC, macrophages that
attack infectious agents, fight chronic infection
Figure 10.4
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Platelets
Platelets
 Needed for the clotting process
 Normal platelet count = 300,000/mm3
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Blood Cells
Erythrocytes, (RBCs), Leukocytes (WBCs), platelets
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Hematopoiesis
Hematopoiesis: blood cell formation
 Occurs in red bone marrow
 Blood cells derive from stem cell - hemocytoblast
 Erythrocytes last 100 to 120 days, eliminated in
spleen or liver. Lost cells are replaced by division
of hemocytoblasts.
 The fetal liver and spleen are early sites of blood
cell formation, then bone marrow takes over
hematopoiesis by the seventh month
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Hemostasis
Hemostasis: stoppage of blood flow from broken
blood vessel
 Three phases of hemostasis (clotting)
 Platelet plug formation – platelets pile up and
form plug in vessel
 Vascular spasms – serotonin hormone release
causes vessels to narrow, reduce blood loss
 Coagulation – thrombin enzyme triggers
hairlike fibrin to form meshwork of clot.
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Blood Clotting
 Blood usually clots within 3 to 6 minutes
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Blood disorders
Blood Disorders:
 Thrombus: clot in an unbroken blood vessel
 Can be deadly in areas like the heart
 Embolus: A thrombus that breaks away and floats
freely in the bloodstream, can clog other vessels
 Thrombocytopenia: Platelet deficiency
 Hemophilia
 Hereditary bleeding disorder
 Normal clotting factors are missing
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Human Blood Groups
Human Blood Groups: ABO
 Based on the presence or absence of 2 antigens –
Type A and Type B.
 If you have A antigen you have Type A blood, if
you have B antigen you have type B blood.
 If you have both A and B antigen - Type AB
 The lack of these antigens is called Type O
 Blood transfusions must use compatible blood
types. If transfused with an unrecognizable
antigen, immune system will attack/reject blood
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Blood Transfusions
 Blood Transfusions
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Rh Blood Groups
Rh Blood Groups
 Based on presence or absence of Rh antigens
(agglutinogen D)
 Most Americans are Rh+
 Problems can occur in mixing Rh+ blood into a
body with Rh– blood, cells might be attacked.
 Pregnancy: Danger if mom is Rh– and dad is is
Rh+, and child inherits the Rh+ factor. Mother’s
immune system produces antibodies to attack
the Rh+ blood (hemolytic disease of the
newborn)
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ADD TO NOTES:
 LEUKEMIA: Cancer of bone marrow. Produces
large numbers of immature/dysfunctional WBCs.
Body becomes easy prey to disease.
 ANEMIA: Decreased oxygen carrying ability of
RBCs. Can be due to deficient hemoglobin, low
number of RBCs, low iron diet.
 SICKLE CELL ANEMIA: Genetic disorder.
RBCs shaped like crescent, can’t carry oxygen as
well. Causes fatigue, risk of clumping
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings