Download Document

PowerPoint® Lecture Slides
prepared by
Janice Meeking,
Mount Royal College
CHAPTER
17
8th Ed
Blood
© 2011 Pearson Education, Inc.
Blood Composition
2
• Blood: a fluid connective tissue composed of
• Plasma
• Formed elements
• Erythrocytes (red blood cells, or RBCs)
• Leukocytes (white blood cells, or WBCs)
• Platelets
Copyright © 2011 Pearson Education, Inc.
Blood Composition
• Hematocrit
• Percent of blood volume that is RBCs
• 47% ± 5% for males
• 42% ± 5% for females
Copyright © 2011 Pearson Education, Inc.
3
4 Figure 17.1 pg. Page 635
Formed
elements
1 Withdraw
2 Centrifuge the
blood and place
in tube.
blood sample.
Copyright © 2011 Pearson Education, Inc.
Plasma
• 55% of whole blood
• Least dense component
Buffy coat
• Leukocytes and platelets
• <1% of whole blood
Erythrocytes
• 45% of whole blood
• Most dense
component
Figure 16.1
Physical Characteristics and Volume
• Color scarlet to dark red
• pH 7.35–7.45
• 38C
• ~8% of body weight
• Average volume: 5–6 L for males, and 4–5
L for females
Copyright © 2011 Pearson Education, Inc.
5
Functions of Blood
1. Distribution of
•
O2 and nutrients to body cells
•
Metabolic wastes to the lungs and kidneys
for elimination
•
Hormones from endocrine organs to target
organs
Copyright © 2011 Pearson Education, Inc.
6
Functions of Blood
2. Regulation of
•
Body temperature by absorbing and
distributing heat
•
Normal pH using buffers
Copyright © 2011 Pearson Education, Inc.
7
Functions of Blood
8
3. Protection against
•
Blood loss
•
•
Plasma proteins, fibrinogen and platelets
initiate clot formation
Infection
•
Antibodies
•
Complement proteins
•
WBCs defend against foreign invaders
Copyright © 2011 Pearson Education, Inc.
Blood Plasma
• 90% water
• Proteins are mostly produced by the liver
• 60% albumin
• 36% globulins
• 4% fibrinogen
Copyright © 2011 Pearson Education, Inc.
9
Blood Plasma
10
• Nitrogenous by-products of metabolism—
lactic acid, urea, creatinine
• Nutrients—glucose, carbohydrates, amino
acids
• Electrolytes—Na+, K+, Ca2+, Cl–, HCO3–
• Respiratory gases—O2 and CO2
• Hormones
Copyright © 2011 Pearson Education, Inc.
Formed Elements
11
• Only WBCs are complete cells
• RBCs have no nuclei or organelles
• Platelets are cell fragments
• Most formed elements survive in the
bloodstream for only a few days
• Most blood cells originate in bone marrow and
do not divide
Copyright © 2011 Pearson Education, Inc.
12 Fig.17.2
Platelets
Monocyte
Pg. 637
Neutrophils
Copyright © 2011 Pearson Education, Inc.
Lymphocyte
Figure 16.2
Erythrocytes
13
• Biconcave discs, anucleate, essentially no
organelles
• Filled with hemoglobin (Hb) for gas transport
• Contain the plasma membrane proteins
• Provide flexibility to change shape as
necessary
• Are the major factor contributing to blood
viscosity
Copyright © 2011 Pearson Education, Inc.
14 fig. 17.3
Pg. 637
2.5 µm
Side view (cut)
7.5 µm
Top view
Copyright © 2011 Pearson Education, Inc.
Figure 16.3
Erythrocytes
15
• Structural characteristics contribute to gas
transport
• Biconcave shape—huge surface area relative
to volume
• >97% hemoglobin (not counting water)
• No mitochondria; ATP production is anaerobic;
no O2 is used in generation of ATP
• 4.3 million -5.8 million / cubic mm
Copyright © 2011 Pearson Education, Inc.
Erythrocyte Function
• RBCs are dedicated to respiratory gas
transport
• Hemoglobin binds reversibly with oxygen
Copyright © 2011 Pearson Education, Inc.
16
Erythrocyte Function
17
• Hemoglobin structure
• Protein globin: two alpha and two beta
chains
• Heme pigment (molecule) bonded to each
globin chain (4)
• Iron atom in each heme can bind to one O2
molecule
• So, each Hb molecule can transport four
O2
Copyright © 2011 Pearson Education, Inc.
18 Fig. 17.4; pg. 638
b Globin chains
Heme
group
a Globin chains
(a) Hemoglobin consists of globin (two
alpha and two beta polypeptide
chains) and four heme groups.
Copyright © 2011 Pearson Education, Inc.
(b) Iron-containing heme pigment.
Figure 16.4
Hemoglobin (Hb)
19
• O2 loading in the lungs
• Produces oxyhemoglobin (ruby red)
• O2 unloading in the tissues
• Produces deoxyhemoglobin or reduced
hemoglobin (dark red)
• CO2 loading in the tissues
• Produces carbaminohemoglobin (carries 20%
of CO2 in the blood) (carbonmonoxide)
Copyright © 2011 Pearson Education, Inc.
Hematopoiesis
20
• Hematopoiesis (hemopoiesis): blood cell
formation
• Occurs in red bone marrow of axial skeleton,
girdles and proximal epiphyses of humerus
and femur
Copyright © 2011 Pearson Education, Inc.
Hematopoiesis
21
• Hemocytoblasts (hematopoietic stem cells)
• Give rise to all formed elements
• Hormones push the cell toward a specific
pathway of blood cell development
Copyright © 2011 Pearson Education, Inc.
22 Figure 17.5 pg. 639
Copyright © 2011 Pearson Education, Inc.
Stem cell
Committed
cell
Developmental pathway
Proerythroblast
Early
Late
erythroblast erythroblast
Hemocytoblast
Copyright © 2011 Pearson Education, Inc.
Phase 1
Ribosome
synthesis
Phase 2
Hemoglobin
accumulation
Phase 3
Ejection of
nucleus
Normoblast
Reticulo- Erythrocyte
cyte
Figure 16.5
Fate and Destruction of Erythrocytes
24
• Life span: 100–120 days
• Old RBCs become fragile, and Hb begins to
degenerate
• Macrophages engulf dying RBCs in the
spleen
Copyright © 2011 Pearson Education, Inc.
Erythrocyte Disorders
25
• Anemia: blood has abnormally low O2carrying capacity
• A sign rather than a disease itself
• Blood O2 levels cannot support normal
metabolism
• Accompanied by fatigue, paleness, shortness
of breath, and chills
Copyright © 2011 Pearson Education, Inc.
Causes of Anemia
26
2. Low hemoglobin content
• Iron-deficiency anemia
• Secondary result of hemorrhagic anemia or
• Inadequate intake of iron-containing foods
• Impaired iron absorption – folic acid
• Hemorrhaging: Ulcers
• Black stool vs. frank blood
Copyright © 2011 Pearson Education, Inc.
Causes of Anemia
27
• Sickle-cell anemia
• Defective gene codes for abnormal
hemoglobin (HbS)
• Causes RBCs to become sickle shaped in
low-oxygen situations
Copyright © 2011 Pearson Education, Inc.
28 Fig. 17.8 pg. 642
(a) Normal erythrocyte has normal
hemoglobin amino acid sequence
in the beta chain.
1
2
3
4
5
6
7
146
(b) Sickled erythrocyte results from
a single amino acid change in the
beta chain of hemoglobin.
1
2
3
4
5
6
7
146
Copyright © 2011 Pearson Education, Inc.
Figure 16.8
Leukocytes
29
• Make up <1% of total blood volume
• Can leave capillaries via diapedesis
• Move through tissue spaces by ameboid
motion and positive chemotaxis
• Leukocytosis: WBC count over 11,000/mm3
• Normal response to bacterial or viral invasion
Copyright © 2011 Pearson Education, Inc.
30 Fig. 17.9
pg.644
Differential
WBC count
(All total 4800 –
10,800/l)
Formed
elements
Platelets
Leukocytes
Granulocytes
Neutrophils (50 – 70%)
Eosinophils (2 – 4%)
Basophils (0.5 – 1%)
Erythrocytes
Agranulocytes
Lymphocytes (25 – 45%)
Monocytes (3 – 8%)
Copyright © 2011 Pearson Education, Inc.
Figure 16.9
Granulocytes
31
• Granulocytes: neutrophils, eosinophils, and
basophils
• Cytoplasmic granules stain specifically with
Wright’s stain
• Larger and shorter-lived than RBCs
• Lobed nuclei
• Phagocytic
Copyright © 2011 Pearson Education, Inc.
Neutrophils
32
• Most numerous WBCs
• Polymorphonuclear leukocytes (PMNs)
• Fine granules take up both acidic and basic
dyes
• Give the cytoplasm a lilac color
• Granules contain hydrolytic enzymes or
defensins
• Very phagocytic—“bacteria slayers”
Copyright © 2011 Pearson Education, Inc.
Eosinophils
33
• Red-staining, bilobed nuclei
• Red to crimson (acidophilic) coarse,
lysosome-like granules
• Digest parasitic worms that are too large to be
phagocytized
• Modulators of the immune response
Copyright © 2011 Pearson Education, Inc.
Basophils
34
• Rarest WBCs
• Large, purplish-black (basophilic) granules
contain histamine
• Histamine: an inflammatory chemical that acts
as a vasodilator and attracts other WBCs to
inflamed sites
• Are functionally similar to mast cells
(histamines & heparin)
Copyright © 2011 Pearson Education, Inc.
35 Fig. 17.10 a b c pg. 644
(a) Neutrophil;
multilobed
nucleus
Copyright © 2011 Pearson Education, Inc.
(b) Eosinophil;
bilobed nucleus,
red cytoplasmic
granules
(c) Basophil;
bilobed nucleus,
purplish-black
cytoplasmic
granules
Figure 16.10 (a-c)
Agranulocytes
36
• Agranulocytes: lymphocytes and monocytes
• Lack visible cytoplasmic granules
• Have spherical or kidney-shaped nuclei
Copyright © 2011 Pearson Education, Inc.
Lymphocytes
37
• Large, dark-purple, circular nuclei with a thin
rim of blue cytoplasm
• Mostly in lymphoid tissue; few circulate in the
blood
• Crucial to immunity
Copyright © 2011 Pearson Education, Inc.
Lymphocytes
38
• Two types
• T Cells: Regulatory T’s: identify antigens
Killer T’s: Kill identified cells
• B cells produce humeral immunity – protein
antibodies circulating in the blood
Copyright © 2011 Pearson Education, Inc.
Monocytes
• The largest leukocytes
• Abundant pale-blue cytoplasm
• Dark purple-staining, U- or kidney-shaped
nuclei
Copyright © 2011 Pearson Education, Inc.
39
40 Monocytes PHYSIOLOGY - SKIP
• Leave circulation, enter tissues, and
differentiate into macrophages
• Actively phagocytic cells; crucial against
viruses, intracellular bacterial parasites, and
chronic infections
• Activate lymphocytes to mount an immune
response
Copyright © 2011 Pearson Education, Inc.
41
Never let monkeys eat bananas
Neutrophils-Lymphocytes-Monocytes-EosinophilsBasophils
Let monkeys are agranulocytes
Copyright © 2011 Pearson Education, Inc.
42 fig. 17.10 a & b
Copyright © 2011 Pearson Education, Inc.
43. Fig 17.10 c
page 644
Copyright © 2011 Pearson Education, Inc.
44 fig.
17.10; pg.
644
(d) Small
lymphocyte;
large spherical
nucleus
Copyright © 2011 Pearson Education, Inc.
(e) Monocyte;
kidney-shaped
nucleus
Figure 16.10d, e
45 Table 17.2; pg. 645
Copyright © 2011 Pearson Education, Inc.
Table 16.2 (1 of 2)
46 Table 17.2; pg. 645
Copyright © 2011 Pearson Education, Inc.
Table 16.2 (2 of 2)
Leukopoiesis
47
• Production of WBCs
• Stimulated by chemical messengers from
bone marrow and mature WBCs
• All leukocytes originate from hemocytoblasts
Copyright © 2011 Pearson Education, Inc.
48
Table
17.11;
page
645
Stem cells
Hemocytoblast
Lymphoid stem cell
Myeloid stem cell
Committed
cells
Myeloblast
Developmental Promyelocyte
pathway
Myeloblast
Myeloblast
Monoblast
Lymphoblast
Promyelocyte Promyelocyte Promonocyte
Eosinophilic Basophilic
myelocyte
myelocyte
Neutrophilic
myelocyte
Eosinophilic Basophilic
band cells
band cells
Neutrophilic
band cells
Monocytes
Eosinophils Basophils Neutrophils
(a)
(b)
(c)
(d)
Granular leukocytes
Copyright © 2011 Pearson Education, Inc.
Prolymphocyte
Lymphocytes
(e)
Agranular leukocytes
Some become
Some
become
Figure 16.11
Leukocyte Disorders
49
• Leukopenia
• Abnormally low WBC count—drug induced
• Leukemias
• Cancerous conditions involving WBCs
• Named according to the abnormal WBC clone involved
• Myelocytic leukemia involves myeloblasts
• Lymphocytic leukemia involves lymphocytes
• Acute leukemia involves blast-type cells and primarily
affects children
• Chronic leukemia is more prevalent in older people
Copyright © 2011 Pearson Education, Inc.
Platelets
50
• Small fragments of megakaryocytes
• Formation is regulated by thrombopoietin
• Blue-staining outer region, purple granules
• Granules contain serotonin, Ca2+, enzymes,
ADP, and platelet-derived growth factor
(PDGF)
Copyright © 2011 Pearson Education, Inc.
Platelets
51
• Form a temporary platelet plug that helps seal breaks
in blood vessels
• Circulating platelets are kept inactive and mobile by
NO and prostacyclin from endothelial cells of blood
vessels
Copyright © 2011 Pearson Education, Inc.
52 Figure: 17.12; pg. 648
Stem cell
Developmental pathway
Hemocytoblast
Promegakaryocyte
Megakaryoblast
Megakaryocyte
Copyright © 2011 Pearson Education, Inc.
Platelets
Figure 16.12
Diagnostic Blood Tests
53
• Hematocrit
• Hemoglobin: 14g – 20g/100ml of blood
• Blood glucose tests
• Microscopic examination reveals variations in
size and shape of RBCs, indications of
anemias
Copyright © 2011 Pearson Education, Inc.
Diagnostic Blood Tests
54
• Differential WBC count
• Prothrombin time and platelet counts assess
hemostasis
• SMAC, a blood chemistry profile
• Complete blood count (CBC)
Copyright © 2011 Pearson Education, Inc.