Chapter 16 Blood
Apr 02, 2015
Chapter 16
Blood
About this Chapter
• Plasma and the cellular elements of blood• Blood cell production• Red blood cells• Platelets and coagulation
Composition of Blood
Figure 16-1 (1 of 2)
BLOOD
Gases such as
such asPlasma
Ions
Trace elementsand vitamins
O2
CO2
Proteins
Glucose
Lipids
Nitrogenouswaste
Globulins
Fibrinogen
Amino acids Albumins
Organicmolecules
Water
iscomposed
of
Composition of Blood
Figure 16-1 (2 of 2)
Cellularelements
Red bloodcells
Whiteblood cells
Platelets
Lymphocytes
Monocytes
Neutrophils
Eosinophils
Basophils
include
m 0
5
10
15
BLOODis
composedof
Plasma Proteins
Table 16-1
Cellular Elements
• Three main cellular elements• Red blood cells – also called erythrocytes• Platelets – split off from megakaryocytes• White blood cells – also called leukocytes• Lymphocytes – are also called immunocytes• Monocytes – develop into macrophages• Neutrophils – neutrophils along with monocytes
and macrophages are known as phagocytes• Eosinophils – eosinophils along with neutrophils
and basophils are also called granulocytes• Basophils – tissue basophils are called mast cells
Hematopoiesis
Figure 16-2 (1 of 2)
Uncommittedstem cells
Pluripotent hematopoietic stem cell
Committedprogenitor cells
Erythroblast
Megakaryocyte
Lymphocytestem cells
BO
NE M
AR
RO
W
Hematopoiesis
Figure 16-2 (2 of 2)
Erythroblast
Megakaryocyte
Reticulocyte
Erythrocyte Platelets Basophil EosinophilNeutrophil Monocyte Lymphocyte
BO
NE M
AR
RO
WC
IRC
ULA
TIO
N
Blood Cells
Table 16-2
Clinical Tests
• Hematocrit: ratio of red blood cells to plasma
Figure 16-3
100%
�58%plasmavolume
42%packedred cellvolume
<1%whitecells
MALES FEMALES
Hematocrit 40%–54% 37%–47%
Hemoglobin (g Hb/dL* blood) 14–17 12–16
Red cell count (cells/µL) 4.5–6.5 x 106 3.9–5.6 x 106
Total white cell count (cells/µL) 4–11 x 103 4–11 x 103
Differential white cell count
Neutrophils 50%–70% 50%–70%
Eosinophils 1%–4% 1%–4%
Basophils <1% <1%
Lymphocytes 20%–40% 20%–40%
Monocytes 2%–8% 2%–8%
Platelets (per µL) 150–450 x 103 150–450 x 103
*1 deciliter (dL) = 100 mL
Focus on … Bone Marrow
Figure 16-4a
(a)
Bonemarrow
Focus on … Bone Marrow
Figure 16-4b
Bonecortex
Central sinus
Venoussinuses
Stroma ofmarrow
(b)
Nutrientartery
Radialartery
Focus on … Bone Marrow
Figure 16-4c
Platelets
Reticular cell
Stem cell
Mature blood cells squeezethrough the endothelium to
reach the circulation.
Fragments of megakaryocytebreak off to become platelets.
The stroma is composed offibroblast-like reticular cells,
collagenous fibers, andextracellular matrix.
Reticulocyteexpellingnucleus
Stem cell
Monocyte
(c)
Lymphocyte
Macrophage
Venous sinus
Matureneutrophil
Reticularfiber
Red Blood Cells
Figure 16-5
CytoskeletonfilamentAttachmentprotein
Actin(a) SEM shows biconcave disk shapeof RBCs.
(b) Cross section of RBC
(c) The cytoskeleton creates theunique shape of RBCs.
Osmotic Changes to Red Blood Cells
• The disk-like structure of red blood cells allows them to modify their shape in response to osmotic changes
Figure 16-6
Iron Homeostasis and Metabolism
Figure 16-7
1
2
3
4
5
6
7
8
88 7
4
6
532
1Intestine
Liver
Bone Marrow
Kidney
Spleen
Iron (Fe)in diet
Fe ・ transferrinFe Fe Heme Hb RBCsynthesis
Old RBCsdestroyed
Hb
Bilirubin +metabolites
Bilirubinmetabolites
in feces
Bilirubinmetabolites
in urine
Ferritin
Bilirubinmetabolism
Bile
Hb
Bilirubin
Plasma
RBC
Iron comes from the diet.
Fe absorbed by activetransport.
Transferrin proteintransports Fe in plasma.
Liver stores excess Fe asferritin.
Bone marrow uses Fe tomake hemoglobin (Hb).
Spleen converts Hb tobilirubin.
Liver metabolizes bilirubinand excretes it in bile.
Bilirubin metabolites areexcreted in urine and feces.
Red Blood Cells
• Live for about 120 days• Hemoglobin components are recycled• Amino acids are incorporated into new proteins• Some iron from heme groups reused in new
heme groups• Remnants of heme groups are converted to
bilirubin, then excreted as bile• Jaundice results from elevated levels of bilirubin
Red Blood Cells
Table 16-3
Figure 16-8
Sickled Red Blood Cells
• Morphology can provide clues to the presence of disease
Platelets Form from Megakaryocytes
Figure 16-9a
Megakaryocytes are giant cells withmultiple copies of DNA in the nucleus.
Endoplasmicreticulum
Platelets
Red blood cell
(a)
The edges of the megakaryocytebreak off to form cell fragmentscalled platelets
3
2
1
Damage towall of
blood vessel
Tissue factorexposed
Intact bloodvessel wall
Clot: reinforcedplatelet plug
Fibrin slowlydissolved by
plasmin
Clot dissolves
Collagenexposed
Platelets aggregateinto loose platelet
plug
Temporaryhemostasis
Cell growth andtissue repair
Vasoconstriction
Platelets adhere and
releaseplateletfactors
Thrombinformation
Coagulationcascade
Convertsfibrinogen
to fibrin
Overview of Hemostasis and Tissue Repair
Figure 16-10
Platelet Plug Formation
Figure 16-11
1
2
3
4
2
4
3
Preventsplatelet
adhesion
Lumen ofblood vessel
Intactendothelium
Smoothmuscle cells
Collagensubendothelial
layer
Exposed collagenin damaged blood
vessel wall
ECF
Releasesprostacyclin
and NO
Exposed collagen bindsand activates platelets.
Release of platelet factors
Factors attract more platelets.
Platelets aggregate intoplatelet plug.
1
Clotting Process
Table 16-4
The Coagulation Cascade
Figure 16-12
INTRINSIC PATHWAY
COMMON PATHWAY
EXTRINSIC PATHWAY
Cross-linked fibrin
Thrombin
Fibrin
Active IX
Active X
Active XIII
Tissue factor(III) and
active VII
Collagen or otheractivators
Damage exposestissue factor (III)
Active XII
Active XI
XII
VIII
VII
IX
XI
Ca2+
Ca2+
Ca2+
Ca2+
Fibrinogen
Prothrombin
Ca2+,V, PL
,positive feedback
positive feedback
phospholipids (PL)X
XIII
Coagulation and Fibrinolysis
Figure 16-13
Thrombin Plasminogen
Fibrinpolymer
Plasmin
tPA
Fibrinfragments
Coagulation Fibrinolysis
Fibrinogen
Clot
Coagulation
Table 16-5
Coagulation
Table 16-6
Coagulation
Figure 16-14
Summary
• Plasma and cellular elements• Plasma, red blood cells, white blood cells,
platelets, and megakaryocytes• Plasma proteins and their functions• Five types of white blood cells
• Blood cell production• Hematopoiesis and cytokines
Summary
• Red blood cell• Transferrin, ferritin, bilirubin, bile, and jaundice
• Platelets and coagulation• Hemostasis, platelet plug, platelet adhesion,
platelet aggregation, and fibrin• Coagulation cascade, fibrinogen, thrombin,
plasmin, prostacyclin, and anticoagulants