© 2012 Pearson Education, Inc.
20The Cardiovascular System: Blood
PowerPoint® Lecture Presentations prepared bySteven BassettSoutheast Community College Lincoln, Nebraska
© 2012 Pearson Education, Inc.
Introduction
• The cardiovascular system functions as asystem to transport numerous substancesthroughout the body such as:
• Nutrients• Oxygen and carbon dioxide• Hormones • Ions • Transports metabolic wastes to the kidneys• Transports leukocytes to aid in fighting
infectious agents
© 2012 Pearson Education, Inc.
Composition of the Blood
• Blood consists of two components• Plasma
• Liquid matrix of blood
• Formed elements: blood cells and cell fragments that are suspended in the plasma, and include:
• Erythrocytes (red blood cells): transport oxygen and carbon dioxide
• Leukocytes (white blood cells): function in the immune system
• Platelets: involved in blood clotting
© 2012 Pearson Education, Inc.
Composition of the Blood
• Whole blood • Males: 4–6 liters• Females: 4–5 liters• Hypovolemic: low blood volumes• Normovolemic: normal blood volumes• Hypervolemic: excessive blood volumes• pH: 7.35–7.45• Temperature = 100.4°F
© 2012 Pearson Education, Inc.
Composition of the Blood
• Plasma• Makes up about 55% of the volume of whole
blood• Consists of:
• 92% water• 7% proteins:
• Albumin• Globulins: involved in immune responses• Fibrinogen: involved in clot formation
• 1% other solutes (electrolytes, organic nutrients, organic waste)
© 2012 Pearson Education, Inc.
Figure 20.1b The Composition of Whole Blood (Part 1 of 2)
Plasma Proteins
Other Solutes
Regulatoryproteins(1%)
Fibrinogen(4%)
Globulins(35%)
Albumins(60%)
Major contributors to osmoticpressure of plasma; transportlipids, steroid hormones
Transport ions, hormones, lipids;immune function
Essential component of clottingsystem; can be converted toinsoluble fibrin
Enzymes, proenzymes,hormones
Electrolytes
Organicnutrients
Organicwastes
Normal extracellular fluid ioncomposition essential for vitalcellular activitiesIons contribute to osmoticpressure of body fluidsMajor plasma electrolytesare Na, K, Ca2, Mg2, Cl,HCO3
, HPO4, SO4
2
Used for ATP production, growth,and maintenance of cells; includelipids (fatty acids, cholesterol,glycerides), carbohydrates(primarily glucose), and aminoacids
Carried to sites of breakdown orexcretion; include urea, uric acid,creatinine, bilirubin, ammoniumions
Components ofplasma
PLASMA COMPOSITION
Plasma proteins
Other solutes
Water
Transports organic andinorganic molecules,formed elements, and heat
7%
1%
92%
Plasma(46–63%)
consists of
Sample ofwhole blood
© 2012 Pearson Education, Inc.
Composition of the Blood
• Formed elements• Makes up about 45% of whole blood• Platelets (<0.1% of whole blood)• Leukocytes (<0.1% of whole blood)
• Neutrophils (50–70% of the WBCs)• Eosinophils (2–4% of the WBCs)• Basophils (<1% of the WBCs)• Lymphocytes (20–30% of the WBCs)• Monocytes (2–8% of the WBCs)
• Erythrocytes (99.9% of whole blood)
© 2012 Pearson Education, Inc.
Figure 20.1c The Composition of Whole Blood (Part 1 of 2)
consists of
Sample ofwhole blood
Formed elementsof blood
Formedelements(37–54%)
FORMED ELEMENTS
Platelets
White blood cells
Red blood cells
0.1%
0.1%
99.9%
Platelets
White Blood Cells
Red Blood Cells
Basophils(1%)
Lymphocytes(20–30%)
Monocytes(2–8%)
Neutrophils(50–70%)
Eosinophils(2–4%)
© 2012 Pearson Education, Inc.
Formed Elements
Red blood cells (RBC) or erythrocytes Most numerous cell Transports oxygen and carbon dioxide Usually degenerate after roughly 120 days in circulation They lack nucleus, mitochondriae and ribosomes. Percentage value of RBC count is called hematocrit.
Elevated hematocrit causes polycythemia. Hemoglobin (Hb)
Give RBCs the ability to transport oxygen and carbon dioxide
Reduced oxygen-carrying capacity of the blood is called anemia.
© 2012 Pearson Education, Inc.
Figure 20.2a Histology of Red Blood Cells
Blood smear LM 477
When viewed in a standardhistological blood smear, red bloodcells appear as two-dimensionalobjects because they are flattenedagainst the surface of the slide.
© 2012 Pearson Education, Inc.
Figure 20.2bc Histology of Red Blood Cells
SEM 1838Red blood cells
A scanning electron micrograph of red blood cells reveals their three-dimensional structure quite clearly.
0.45–1.16 m 2.31–2.85 m
7.2–8.4 m
A sectional view of a red blood cell
© 2012 Pearson Education, Inc.
Figure 20.3 The Structure of Hemoglobin
Hemoglobinmolecule
Heme
Heme
chain 1
chain 1
chain 2
chain 2
© 2012 Pearson Education, Inc.
Formed Elements
• The blood type is determined at the cellular level by presence or absence of specific antigen on the RBC plasma membrane.– Based on the presence or absence of Ag A and Ag B,
there are blood type A, B, AB and O.– Based on the presence or absence of Ag D or Rh
antigen the blood group can be positive or negative.– O is universal blood donor.– AB is universal blood recipient.
© 2012 Pearson Education, Inc.
Formed Elements
• Blood Types (continued)• People with type A blood have the b
agglutinin in their plasma.• People with type B blood have the a
agglutinin in their plasma.• People with type AB blood have neither
agglutinin a nor agglutinin b in their plasma• People with type O blood have both agglutinin
a and agglutinin b in their plasma.
© 2012 Pearson Education, Inc.
Figure 20.4 Blood Typing
Type A Type B Type AB Type O
Type A blood has RBCs withsurface antigen A only.
Type B blood has RBCs withsurface antigen B only.
Surface antigen A
Surface antigen B
If you have Type A blood, your plasma contains anti-Bantibodies, which will attackType B surface antigens.
If you have Type B blood, your plasma contains anti-Aantibodies.
Type AB individuals do nothave anti-A or anti-Bantibodies.
Type AB blood has RBCswith both A and B surfaceantigens.
Type O blood has RBCslacking both A and B surfaceantigens.
An individual with Type Oblood has plasma containingboth anti-A and anti-Bantibodies.
Your blood type is a classification determined by the presence or absence of specific surface antigensin RBC plasma membranes. There are four blood types based on the A and B surface antigens.
© 2012 Pearson Education, Inc.
Figure 20.4 Blood Typing
The plasma contains antibodies that will react with foreign surface antigens in a processcalled agglutination. The cells may also break apart, an event known as hemolysis.
RBC
Surface antigens Opposing antibodies Agglutination (clumping) Hemolysis
© 2012 Pearson Education, Inc.
Formed Elements
White blood cells (WBC) or leukocytes Defend body against pathogens and remove
toxins, wastes, and abnormal or damaged cells Two classes:
Granular leukocytes Neutrophils Eosinophils (acidophils)/orange Basophils
Agranular leukocytes Monocytes Lymphocytes
Show chemotaxis (the attraction to specific chemicals) and diapedesis (the ability to move through vessel walls)
© 2012 Pearson Education, Inc.
Figure 20.5 Histology of White Blood Cells
Neutrophil
RBCRBC RBC
LM 1500 LM 1500 LM 1500Eosinophil Basophil Monocyte
RBC
LM 1500 LM 1500
RBC
Lymphocyte
© 2012 Pearson Education, Inc.
Table 20.3 A Review of the Formed Elements of the Blood
© 2012 Pearson Education, Inc.
Formed Elements
Platelets Not cells; they are membrane-enclosed packets of cytoplasm Released into blood by megakaryocytes, enormous cells in the
bone marrow Circulate for 10 —12 days before being removed by phagocytes;
continually replaced Functions
Transport chemicals important for clotting Temporarily patch the walls of damaged blood vessels Causing contraction after a clot has formed to reduce the size
of the break in the vessel wall Hemostasis is obtained by going through the following stages in
order: Vasoconstriction Platelet aggregation Clot formation
© 2012 Pearson Education, Inc.
Figure 20.6 Histology of Megakaryocytes and Platelet Formation
Nutrient artery
Venoussinuses
Red bonemarrow
Developing erythrocytesand granulocytes
Adipocyte
Bone marrow section LM 673
Platelets
MegakaryocyteRed blood
cell
© 2012 Pearson Education, Inc.
Hemopoiesis
The process of blood cell formationAll blood cells are produced in the bone marrow. Stem cells or pluripotential stem cells (PPSC) divide to form all of the blood cells.
Give rise to myeloid stem cells and lymphoid stem cells
Original blood cells form in developing blood vessels.
Spleen and liver contribute in fetal blood cell development
Red bone marrow takes over in postnatal life
© 2012 Pearson Education, Inc.
Figure 20.8 The Origins and Differentiation of Formed Elements
Red bone marrow
Myeloid Stem Cells
Progenitor Cells
PluripotentialStem Cells
Red Blood Cells(RBCs)
Blast Cells
Myelocytes
Band Cells
White Blood Cells (WBCs)
Proerythroblast
Erythroblast stages
Reticulocyte
Ejection ofnucleus
Erythrocyte
Megakaryocyte
Platelets
Myeloblast
Basophil Eosinophil Neutrophil
Granulocytes Agranulocytes
Monoblast Lymphoblast
Promonocyte Prolymphocyte
Monocyte Lymphocyte
Lymphoid Stem Cells