1. Blood 16

3. Composition of Blood
Figure 16-1 (1 of 2)

4. Cellular Elements Three main cellular elements
Platelets split off from megakaryocyte
Five types of mature white blood cells
Monocytes develop into macrophages
Tissue basophils are mast cells
Neutrophils, monocytes and macrophages are known as phagocytes
Lymphocytes are also called immunocytes
Basophils, eosinophils and neutrophils are also called granulocytes

5. Composition of Blood Found in lymphatic system, B- & T-cells
Exit blood stream to become macrophages & APC
Phagocyte for bacteria & secretes cytokines (ex. signal fever)
Phagocyte for parasites & cytokines related to allergies
Mediate inflamation& allegies via cytokine release (histamine)
Figure 16-1 (2 of 2)

6. Hematopoiesis
Signaled by erythropoeitin, a hormone released by the kidneys in response to low O2,
Or by thrombopoetin, colony-stimulating factors, interleukin, & stem cell factor
Figure 16-2

7. Focus on … Bone Marrow
Blood production in adults is limited to the axial skeleton, the humerus,a nd femur.
Figure 16-4a

8. Focus on … Bone Marrow
Overall components of bone marrow include the stroma & sinus capillary. Notice the platelet, RBC, and Neutrophil formation
Platelets
Reticulocyte
expelling
nucleus
Stem
cell
Lymphocyte
Venous
sinus
Monocyte
Reticular cell
Stem cell
Reticular
fiber
(c)
Mature blood
cells squeeze
through the
endothelium to
reach the
circulation.
Fragments of
megakaryocyte
break off to
become platelets.
The stroma is
composed of
fibroblast-like
reticular cells,
collagenous fibers,
and extracellular
matrix.
Macrophage
Mature
neutrophil
Red blood cell maturation
Neutrophil maturation
Figure 16-4c

9. Erythrocytes Transport oxygen and carbon dioxide.
Originate in bone marrow and as they mature they expel their organelles before entering the blood stream.
Most numerous component of formed elements.
Contain no nucleus or organelles, instead they are packed with hemoglobin.
There are three important characteristics of red blood cells:
1. Their concave shape allows for 30%
more surface area for carrying oxygen.
2. 97% of their content is hemoglobin.
It is used for binding both oxygen &
CO2
3. They depend on anaerobic
respiration thus they do not consume
any oxygen

10. Osmotic Changes to Red Blood Cells
Morphology of red blood cells can provide clues to the presence of disease. Diagram shows cells in solutions of different salt concentrations. However, some disorders do are due to abnormal RBC shape.
Figure 16-6

11. Sickled Red Blood Cells
A single genetic mutation error in one amino acids produces a proteins with an irregular shape causing many problems
Figure 16-8

12. Iron Metabolism
Normally the body stores iron but women need to consume more iron than men. Why?
Figure 16-7

13. Red Blood Cells
Live for about 120 days- old cells get broken at the spleen or cleared by macrophages
Hemoglobin components are recycled- iron is reused to make new hemoglobin
Remnants of heme groups – the other components are taken to the liver and become components of bile
Bilirubin is excreted in bile and gives bile its green color
Jaundice- yellowing of the skin, nail, and sclera in eyes due to elevated blood levels of bilirubin resulting form liver malfunction.

14. Hemostasis (not homeostasis)
Keeps blood within blood vessels (hemorrhage does not)
Requires: 1- vasoconstriction, 2- platelet plug formation, 3- blood coagulation (seal hole)
Coagulation cascade results in formation of fibrin, a fiber mesh that stabilizes the platelet plug=clot
Plasmin is an enzyme that dissolves the clot as the tissue heals
A thrombus results from too much clot formation and can block a blood vessel

15. Platelet Plug Formation
Figure 16-11

16. Overview of Hemostasis and Tissue Repair
Diagram displays the mechanisms for restoring broken blood vessels
Damage to
wall of
blood vessel
Tissue factor
exposed
Intact blood
vessel wall
Reinforced
platelet plug (clot)
Fibrin slowly
dissolved by
plasmin
Clot dissolves
Collagen
Platelets aggregate
into loose platelet
plug
Temporary
hemostasis
Cell growth and
tissue repair
Vasoconstriction
Platelets
adhere and
release
platelet
factors
Thrombin
formation
Coagulation
cascade
Converts
fibrinogen
to fibrin
Figure 16-10

17. The Coagulation Cascade
Intrinsic Pathway begins when collagen is exposed
Extrinsic pathway is activated by damaged tissues
Thrombin is need to created fibrin- the insoluble fibers create the clot.
Positive feedback loops remain until a component is consumed
Figure 16-12

18. Coagulation and Fibrinolysis
Clot formation is limited to prevent the entire blood content from coagulating.
Figure 16-13

19.
gslc.genetics.utah.edu/.../ABObloodsystem.gif

20. Rh antigens and antibodies
Blood Types
Antigens on RBCs
A, B, AB or none (O)
Antibodies in plasma
Anti A, anti B, anti AB
Rh antigens and antibodies