1. Chapter 18 Lecture PowerPoint
To run the animations you must be in Slideshow View. Use the buttons on the animation to play, pause, and turn audio/text on or off.
Please Note: Once you have used any of the animation functions (such as Play or Pause), you must first click in the white background before you can advance to the next slide.
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

2. The Circulatory System: Blood
Introduction
Erythrocytes
Blood types
Leukocytes
Platelets and Hemostasis – The Control of Bleeding
18-2

3. Circulatory System functions of circulatory system transport
O2, CO2, nutrients, wastes, hormones, stem cells
protection
inflammation, limit spread of infection, destroy microorganisms and cancer cells, neutralize toxins, initiates clotting
regulation
fluid balance, stabilizes pH of ECF, temperature control
18-3

4. Components and General Properties of Blood
adults have 4-6 L of blood
a liquid connective tissue consisting of cells and extracellular matrix
plasma – matrix of blood
a clear, light yellow fluid
formed elements - blood cells and cell fragments
red blood cells, white blood cells, and platelets
18-4

5. Components and General Properties of Blood
seven kinds of formed elements
erythrocytes - red blood cells (RBCs)
platelets
cell fragments from special cell in bone marrow
leukocytes - white blood cells (WBCs) – 5 types
18-5

6. Formed Elements of Blood
Monocyte
Small
lymphocyte
Neutrophil
Platelets
Eosinophil
Small
lymphocyte
Erythrocyte
Young (band)
neutrophil
Neutrophil
Monocyte
Large
lymphocyte
Neutrophil
Basophil
Figure 18.1
18-6

7. Separating Plasma From Formed Elements of Blood
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Withdraw
blood
hematocrit - centrifuge blood to separate components
erythrocytes
heaviest - settle first
37% to 52% total volume
white blood cells and platelets
1% total volume
buffy coat
plasma
47% - 63%
complex mix of water, proteins, nutrients, electrolytes, nitrogenous wastes, hormones, and gases
Centrifuge
Plasma
Buffy coat: leukocytes
and platelets
Erythrocytes
Formed
elements
Figure 18.2
18-7

8. Plasma and Plasma Proteins
plasma – liquid portion of blood
3 major categories of plasma proteins
albumins – smallest and most abundant
contributes to viscosity and osmolarity, influences blood pressure, flow and fluid balance
globulins (antibodies)
provide immune system functions
fibrinogen
helps form blood clots
Other substances in blood – glucose, waste, electrolytes
18-8

9. Properties of Blood
osmolarity of blood - the total molarity of those dissolved particles that cannot pass through the blood vessel wall
if too high, blood absorbs too much water, increasing the blood pressure
if too low, too much water stays in tissue, blood pressure drops and edema occurs
optimum osmolarity is achieved by body’s regulation of sodium ions, proteins, and red blood cells.
18-9

10. Starvation and Plasma Proteins
Blood
Tissue
hypoproteinemia
deficiency of plasma proteins
extreme starvation
liver or kidney disease
severe burns
kwashiorkor
children with severe protein deficiency
fed on cereals once weaned
thin arms and legs
swollen abdomen
protein
Water flows into tissue by osmosis
18-10

11. ?

12. Erythrocytes two principal functions:
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Capillary
wall
Erythrocytes
Figure 18.4c
(c)
7 µm
two principal functions:
carry oxygen from lungs to cell tissues
pick up CO2 from tissues and bring to lungs
Not enough RBC’s not enough O2 rapid death
18-12

13. Erythrocytes (RBCs) disc-shaped cell with thick rim
lose nearly all organelles
blood type determined by surface molecules
cytoskeletal proteins give membrane durability and resilience
stretch and bend through small capillaries
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Surfaceview
7.5 µm
2.0 µm
(a)
Sectional view
Figure 18.4a
18-13

14. Hemoglobin (Hb) Structure
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
each Hb molecule consists of:
four protein chains – globins
four heme groups
heme groups
nonprotein moiety that binds O2 to ferrous ion (Fe2+)
Beta
Alpha
Heme
groups
(a)
Alpha
Beta
CH3 CH
CH2 C C HC C C CH C N C
CH3 C C
CH3 N
Fe2+ N
CH2 C C CH
CH2 C N C
CH2 HC C C CH
COOH C C
CH2
CH3
CH2
COOH
(b)
Figure 18.5 a-b
18-14 14

15. Erythrocyte Production (Erythropoiesis)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Pluripotent
stem cell
Colony-forming
unit (CFU)
Precursor
cells
Mature
cell
Erythrocyte CFU
Erythroblast
Reticulocyte
Erythrocyte
Figure 18.6
Produced in red bone marrow
2.5 million RBCs produced per second
average lifespan of about 120 days
development takes 3-5 days
first committed cell - erythrocyte colony forming unit
has receptors for erythropoietin (EPO) from kidneys
18-15

16. Erythrocyte Homeostasis
negative feedback control
drop in RBC count causes kidney hypoxemia
kidney production of erythropoietin stimulates bone marrow
RBC count increases in days
stimuli for increasing erythropoiesis
low levels O2 (hypoxemia)
high altitude
increase in exercise
loss of lung tissue in emphysema
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hypoxemia
(inadequate O2 transport)
Increased
O2 transport
Sensed by liver and kidneys
leaves
Increased
RBC count
Accelerated
erythropoiesis
Secretion of
erythropoietin
Stimulation of
red bone marrow
Figure 18.8
18-16

17. Erythrocyte Disorders
polycythemia - an excess of RBCs
primary polycythemia
cancer of erythropoietic cell line in red bone marrow
secondary polycythemia
from dehydration, emphysema, high altitude, or physical conditioning
dangers of polycythemia
increased blood volume, pressure, viscosity
can lead to embolism, stroke or heart failure
18-17

18. Anemia causes of anemia fall into three categories:
inadequate erythropoiesis or hemoglobin synthesis
kidney failure and insufficient erythropoietin
iron-deficiency anemia
inadequate vitamin B12 from poor nutrition or lack of intrinsic factor (pernicious anemia)
hemorrhagic anemias from bleeding
hemolytic anemias from RBC destruction
18-18

19. Anemia anemia has three potential consequences:
tissue hypoxia and necrosis
patient is lethargic
shortness of breath upon exertion
life-threatening necrosis of brain, heart, or kidney
blood osmolarity is reduced, producing tissue edema
blood viscosity is low
heart races and pressure drops
cardiac failure may ensue
18-19

20. © Meckes/Ottawa/Photo Researchers, Inc.
Sickle-Cell Disease
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
hereditary hemoglobin defect -mostly among people of African descent
recessive allele that modifies the structure of the hemoglobin molecule (HbS)
HbS does not bind oxygen well
RBCs become rigid, sticky, pointed at ends
clump together and block small blood vessels: intense pain
can lead to kidney or heart failure, stroke, rheumatism or paralysis
7 µm
© Meckes/Ottawa/Photo Researchers, Inc.
Figure 18.10
18-20

21. Blood Types RBC antigens called agglutinogens
called antigen A and B
determined by molecules found on RBC surface
antibodies called agglutinins
found in plasma
anti-A and anti-B
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Type O
Type B
leaves
Type A
Type AB
Key
Galactose
Fucose
N-acetylgalactosamine
Figure 18.12
18-21

22. ABO Group
your ABO blood type is determined by presence or absence of antigens (agglutinogens) on RBCs
blood type A person has A antigens
blood type B person has B antigens
blood type AB has both A and B antigens
blood type O person has neither antigen
most common - type O
rarest - type AB
18-22

23. Plasma Antibodies antibodies (agglutinins); anti-A and anti-B
we have antibodies to the antigens we don’t have (if you are type A, you have anti-B; if you are type O, you have anti-A and anti-B, etc.)
agglutination
each antibody can attach to several foreign antigens on several different RBCs at the same time - clumps the blood
18-23

24. Agglutination of Erythrocytes
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Antibodies
(agglutinins)
Figure 18.13
18-24

25. Transfusion Reaction Figure 18.15 Blood from type A donor Type B
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Blood from
type A donor
leaves
Type B
(anti-A)
recipient
Donor RBCs
agglutinated by
recipient plasma
Agglutinated RBCs
block small vessels
Figure 18.15
18-25

26. ?

27. Leukocytes (WBCs) least abundant formed element
protect against infectious microorganisms and other pathogens
conspicuous nucleus
spend only a few hours in the blood stream before migrating to connective tissue
retain their organelles for protein synthesis
18-27

28. Types of Leukocytes granulocytes agranulocytes neutrophils (60-70%)-
eosinophils (2-4%)
basophils (<1%)
agranulocytes
lymphocytes (25-33%)
monocytes (3-8%)
18-28

29. Granulocytes Figure TA 18.1 Figure TA 18.2 Figure TA 18.3 Neutrophils
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Neutrophils
10 µm
Eosinophil
10 µm
Basophil
10 µm
all: © Ed Reschke
Figure TA 18.1
Figure TA 18.2
Figure TA 18.3
18-29

30. both: Michael Ross/Photo Researchers, Inc.
Agranulocytes
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Lymphocyte
10 µm
Monocyte
10 µm
both: Michael Ross/Photo Researchers, Inc.
Figure TA 18.4
Figure TA 18.5
18-30

31. Leukopoiesis Figure 18.18 Eosinophil Basophil Neutrophil Monocyte
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Pluripotent
stem cell
Colony-forming
units (CFUs)
Precursor
cells
Mature
cells
Eosinophil
leaves
Eosinophilic
CFU
Eosinophilic
myeloblast
Eosinophilic
promyelocyte
Eosinophilic
myelocyte
Basophil
Basophilic
CFU
Basophilic
myeloblast
Basophilic
promyelocyte
Basophilic
myelocyte
Neutrophil
Neutrophilic
CFU
Neutrophilic
myeloblast
Neutrophilic
promyelocyte
Neutrophilic
myelocyte
Monocyte
Monocytic
CFU
Monoblast
Promonocyte
B lymphocyte
B prolymphocyte
T lymphocyte
T prolymphocyte
Lymphocytic
CFU
Lymphoblast
Figure 18.18
NK cell
18-31
NK prolymphocyte

32. Leukocyte Disorders leukopenia - low WBC count below 5000/L
causes: radiation, poisons, infectious disease
effects: elevated risk of infection
leukocytosis - high WBC count above 10,000/L
causes: infection, allergy and disease
differential WBC count – identifies what percentage of the total WBC count consists of each type of leukocyte
patient subject to opportunistic infection, anemia
18-32 32

33. Leukocyte Disorders
leukemia - cancer of hemopoietic tissue - produces an extremely high number of circulating leukocytes and their precursors
myeloid leukemia – uncontrolled granulocyte production
lymphoid leukemia - uncontrolled lymphocyte or monocyte production
acute leukemia – appears suddenly, progresses rapidly, death within months
chronic leukemia –undetected for months, survival time three years
effects - impaired clotting; opportunistic infections
patient subject to opportunistic infection, anemia
18-33 33

34. Normal and Leukemic Blood
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Platelets
Monocyte
Neutrophils
Lymphocyte
Erythrocytes
(a)
Figure a-b
(b)
75 µm
18-34
© Ed Reschke

35. ?

36. Hemostasis hemostasis – the cessation of bleeding
stopping potentially fatal leaks
hemorrhage – excessive bleeding
three hemostatic mechanisms
vascular spasm
platelet plug formation
blood clotting (coagulation)
platelets play an important role in all three
18-36

37. Platelets platelets - small fragments of megakaryocyte cells functions
secrete vasoconstrictors that help reduce blood loss
stick together to form platelet plugs to seal small breaks
secrete procoagulants or clotting factors promote clotting
chemically attract neutrophils and monocytes to sites of inflammation
phagocytize and destroy bacteria
18-37

38. all 3 pathways involve platelets
Hemostasis
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Vasoconstriction
Platelet
plug
Blood
clot
Platelet
Vessel
injury
Collagen
fibers
Endothelial
cells
(a) Vascular spasm
(b) Platelet plug formation
(c) Coagulation
Figure a-c
all 3 pathways involve platelets
18-38

39. Hemostasis - Vascular Spasm
vascular spasm - prompt constriction of a broken vessel
most immediate protection against blood loss
causes:
pain receptors
some directly innervate blood vessels to constrict
smooth muscle injury
platelets release serotonin (vasoconstrictor)
effects:
prompt constriction of a broken vessel
provides time for other two clotting pathways
18-39

40. Hemostasis -Platelet Plug Formation
broken vessel exposes collagen
platelet pseudopods stick to damaged collagen and other platelets - pseudopods contract and draw walls of vessel together platelet plug
platelets degranulate releasing a variety of substances
positive feedback cycle is active until break in small vessel is sealed
18-40

41. Hemostasis - Coagulation
coagulation (clotting) – last and most effective defense against bleeding
conversion of plasma protein fibrinogen into insoluble fibrin threads to form framework of clot
procoagulants (clotting factors), usually produced by the liver, are present in plasma
activate one factor and it will activate the next to form a reaction cascade
18-41

42. © P. Motta/SPL/Photo Researchers, Inc.
SEM of Blood Clot
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Figure 18.22
© P. Motta/SPL/Photo Researchers, Inc.
18-42

43. Enzyme Amplification in Clotting
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Factor
XII
Factor XI
Factor IX
Figure 18.24
Factor
VIII
Reaction cascade (time)
Factor X
Prothrombin
activator
Thrombin
Fibrin
rapid clotting - each activated cofactor activates many more molecules in next step of sequence
18-43

44. Clotting Disorders - Hemophilia
deficiency of any clotting factor can shut down the coagulation cascade
hemophilia – family of hereditary diseases characterized by deficiencies of one factor or another
sex-linked recessive (on X chromosome)
physical exertion causes bleeding and severe pain
Treatment
transfusion of plasma or purified clotting factors
factor VIII produced by transgenic bacteria
18-44

45. Coagulation Disorders
thrombosis - abnormal clotting in unbroken vessel
thrombus - clot
most likely to occur in leg veins of inactive people
pulmonary embolism - clot may break free, travel from veins to lungs
embolus – anything that can travel in the blood and block blood vessels
infarction (tissue death) may occur if clot blocks blood supply to an organ (MI or stroke)
650,000 Americans die annually of thromboembolism – traveling blood clots
18-45

46. END