Transcript You Light Up My Life - Dutchess Community College

PowerLecture:
Chapter 8
Blood
Learning Objectives




Describe the composition and functions of
blood.
Explain how red blood cells transport
oxygen.
Explain the basis of blood typing.
Define hemostasis and distinguish it from
homeostasis.
Learning Objectives (cont’d)

Describe how blood disorders disrupt
homeostasis and critical body functions,
such as clotting.
Impacts/Issues
Chemical Questions
Chemical Questions
Healthy people have
contaminants in their blood.




The chemicals are products from
everyday life: metals, secondhand
cigarette smoke, pesticides, etc.
Most of the chemicals did not even
exist 50 years ago.
Not enough is known about the
long-term effects of these
chemicals on human health,
especially for the very young.
Useful References for Impacts/Issues
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 Environmental
Scorecard - In Your
Community
 InfoTrac: Elevated Blood Lead Levels in
Refugee Children – New Hampshire, 2003–
2004. Morbidity and Mortality Weekly Report,
Jan. 21, 2005.
How Would You Vote?
To conduct an instant in-class survey using a classroom response
system, access “JoinIn Clicker Content” from the PowerLecture main
menu.
 Government
regulation of substances such
as lead seems to be effective. Should other
suspect industrial chemicals be regulated?


a. Yes, until companies are forced to prove their
chemicals are harmless before selling them, they
should be regulated.
No, regulation hampers industry and is not
necessary unless these chemicals are proven
harmful.
Useful References for
How Would You Vote?
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 CDC:
National Report on Human Exposure to
Environmental Chemicals
 Environmental Working Group: Body Burden
 NRDC: Healthy Milk, Healthy Baby –
Chemical Pollution and Mother’s Milk
Section 1
Blood: Plasma, Blood
Cells, and Platelets
Blood: Plasma, Blood Cells, and Platelets


Blood is a connective
tissue; it contains
plasma, blood cells, and
cell fragments called
platelets.
Adult women of average
size have 4-5 liters of
blood in their bodies;
men have slightly more.
Figure 8.1
red
blood
cell
white
blood
cell
platelets
Fig. 8.1, p.143
Blood: Plasma, Blood Cells, and Platelets
Plasma is the fluid part of blood.



Roughly 55% of whole blood is plasma, which
is mostly water.
Plasma proteins perform a variety of tasks:
•
•

Albumin is important in maintaining osmotic balance
and transports chemicals such as therapeutic drugs.
Other plasma proteins include protein hormones, as
well as proteins involved in immunity, blood clotting,
and the transport of lipids and vitamins.
Plasma further contains ions, glucose, amino
acids, signaling molecules, and dissolved
gases.
Blood: Plasma, Blood Cells, and Platelets
Red blood cells carry oxygen and CO2.


Erythrocytes, or red blood cells, (45% of
whole blood) are biconcave disks.
•
•

They contain hemoglobin, an iron-containing protein
that binds with oxygen.
They also carry a small amount of carbon dioxide.
Red blood cells originate from stem cells in the
bone marrow.
Animation: Cellular Components of Blood
CLICK
TO PLAY
natural
killer cells
neutrophils
eosinophils
mast cells
basophils
T
lymphocytes
B lymphocytes
forerunners
of
white blood
cells
(leukocytes)
?
stem cells
in marrow
red blood
cells
(erythrocytes)
monocytes
(immature
phagocytes)
dendritic cells
megakaryocytes
macrophages
platelets
Fig. 8.2, p.145
Blood: Plasma, Blood Cells, and Platelets
White blood cells perform defense and
cleanup duties.



Leukocytes, or white blood cells, make up a
minor portion of whole blood and are
responsible for housekeeping and defense;
they also are derived from bone marrow.
Leukocytes are of two main types:
•
•
Granulocytes have stainable granules in the
cytoplasm; they include neutrophils, eosinophils, and
basophils; and they work in body defense activities.
Agranulocytes have no visible granules; monocytes
become macrophages; and lymphocytes become B
cells, T cells, and natural killer cells.
Blood: Plasma, Blood Cells, and Platelets
Platelets help clot blood.



Platelets are fragments of megakaryocytes
produced by bone marrow stem cells.
They are short lived, numerous, and function in
blood clotting.
Components
Relative Amounts
Functions
Plasma portion (50%-60% of total volume):
1. Water
91%-92% of
plasma volume
2. Plasma proteins (albumin,
globulins, fibrinogen, etc.)
7%-8%
3. Ions, sugars, lipids, amino acids,
hormones, vitamins, dissolved
gasses
Solvent
Defense, clotting, lipid transport,
roles in extracellular fluid volume,
etc.
1%-2%
Roles in extracellular fluid volume,
pH, etc.
Plasma portion (50%-60% of total volume):
1. White blood cells:
Neutrophils
Lymphocytes
Monocytes(macrophages)
Eosinophils
Basophils
2. Platelets
3. Red blood cells
3,000-6,750
1,000-2,700
150-720
100-360
25-90
250,00-300,000
Phagocytosis during inflammation
Immune responses
Phagocytosis in all defense responses
Defense against parasitic worms
Secrete substances for inflammatory
response and for fat removal from blood
Roles in clotting
4,800,000-5,400,000 Oxygen, carbon dioxide transport
per microliter
Fig. 8.1, p.143
Video: Immortality Industry
 This
video clip is available in CNN Today
Videos for Anatomy and Physiology, 2004,
Volume VIII. Instructors, contact your local
sales representative to order this volume,
while supplies last.
Useful References for Section 1
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 InfoTrac:
FDA to Hear Artificial Blood Test
Proposal. UPI NewsTrack, July 6, 2006.
Section 2
How Blood Transports
Oxygen
How Blood Transports Oxygen
Hemoglobin is the oxygen
carrier.




Only a tiny amount of oxygen
is dissolved in blood plasma.
Most of the oxygen is bound to the heme groups
of hemoglobin; oxygen-bearing hemoglobin is
called oxyhemoglobin.
What determines how much oxygen
hemoglobin can carry?
How Blood Transports Oxygen

The amount of oxygen bound to hemoglobin
changes as conditions in the tissues vary.
•
•
•
Binding of oxygen is favored by conditions in the
lungs: abundant oxygen, cooler temperature, and
neutral pH.
Release of oxygen is favored in the tissues where
the oxygen levels are lower, temperatures higher,
and pH more acidic.
Hemoglobin also transports a small amount of
carbon dioxide.
LUNGS
more O2
cooler
less acidic
Hb + O2
TISSUES
HbO2
HbO2
Hb + O2
less O2
warmer
more acidic
p.146
Animation: Globin and
Hemoglobin Structure
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TO PLAY
How Blood Transports Oxygen

Each hemoglobin molecule has four
polypeptide chains (globin proteins), each of
which possesses a heme group containing an
iron molecule; each iron binds one molecule of
oxygen.
heme group
coiled and twisted
polypeptide chain
of one globin
molecule
Fig. 8.3b, p.146
Useful References for Section 2
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 Royal
Society of Chemistry: Transport of
Oxygen in the Blood
 InfoTrac: Hemoglobin Levels Are Testy Issue.
New York Daily News, Feb. 12, 2006.
Section 3
Hormonal Control of Red
Blood Cell Production
Hormonal Control of
Red Blood Cell Production
Red blood cells form from stem cells
located in red bone marrow.



The hormone erythropoietin from the kidneys
is the stimulus for stem cell division.
Mature red blood cells have no nuclei and live
for only about 120 days.
•
•
Macrophages remove old blood cells from the
bloodstream; amino acids are returned to the blood,
iron is returned to the bone marrow, and heme
groups are converted to bilirubin.
Red cell counts remain rather constant at 5.4
million/microliter for males and 4.8 million for
females.
Hormonal Control of
Red Blood Cell Production
A negative feedback loop stabilizes the red
blood cell count.




The kidneys monitor oxygen content of the
blood; when it drops too low, the kidneys
secrete erythropoietin.
Erythropoietin stimulates bone marrow to
produce more red blood cells; this increases
the ability of the blood to carry oxygen.
As oxygen levels rise, the information feeds
back to the kidneys, which stop secreting
erythropoietin.
Kidney
2
Erythropoietin
1
3
Reduced oxygen
in blood
Developing
red blood cells
in red bone
marrow
Relieves 5
4
1
The kidneys detect
reduced O2 in the blood.
2
When less O2 is delivered to
the kidneys, they secrete the
hormone erythropoietin into
the blood.
3
Erythropoietin stimulates
production of red blood
cells in bone marrow.
4
The additional circulating
RBCs increase O2 carried
in blood.
5
The increased O2 relieves the
initial stimulus that triggered
erythropoietin secretion.
Increased oxygen
in blood
RBCs
Fig. 8.4, p.147
Section 4
Blood Types –
Genetically Different Red
Blood Cells
Blood Types –
Genetically Different Red Blood Cells
All cells of the human body have surface
proteins and other molecules that serve as
“self” identification markers.



Any protein marker that prompts a defensive
action is called an antigen.
The human body produces antibodies that
recognize markers on foreign cells as “nonself”
and stimulate immune reactions.
Blood Types –
Genetically Different Red Blood Cells
The ABO group of blood types includes key
self markers on red blood cells.


ABO blood groups are based on glycoprotein
surface markers on red blood cells.
•
•

Type A has A markers; type B has B markers.
Type AB has both markers; type O has neither
marker.
Depending on ABO blood type, the body will
also possess antibodies to other blood types;
ABO blood typing is done to prevent
incompatible blood types from being mixed.
Blood Types –
Genetically Different Red Blood Cells
Mixing incompatible blood types can cause
the clumping called agglutination.


Type A blood types do not have antibodies
against A markers, but they do have antibodies
to type B; Type B blood types do not have type
B antibodies, but they do have type A
antibodies, etc.
•
•
A type A person cannot donate blood to a type B
person because they are incompatible.
When mixed, markers on the surface of red blood
cells (not just the ABO markers) that do not match
will cause the blood cells to undergo agglutination,
a defense response where the blood cells clump.
Animation: Genetics of ABO Blood Types
CLICK
TO PLAY
Table 8.1, p.148
Table 8.2, p.151
Animation: Transfusions and Blood Types
CLICK
TO PLAY
Blood Types – Genetically Different Red
Blood Cells

Clumped cells can clog small blood vessels,
damage tissues, and cause death.
compatible blood cells
incompatible blood cells
Fig. 8.5b, p. 149
Donor
type B blood
Recipient with
type A blood
Antigen B
Antibody to
type A blood
Antigen A
Antibody to
type B blood
Red blood cells from
donor agglutinated
by antibodies in
recipient’s blood
Red blood cells
usually burst
Clumping blocks blood
flow in capillaries
Side effects disrupt Oxygen and nutrient
kidney function
flow to cells and tissues
is reduced
Fig. 8.5a, p.149
Donor
type B blood
Recipient with
type A blood
Antigen B
Antibody to
type A blood
Antigen A
Antibody to
type B blood
Red blood cells from
donor agglutinated
by antibodies in
recipient’s blood
Red blood cells
usually burst
Side effects disrupt
kidney function
Clumping blocks blood flow
in capillaries
Oxygen and nutrient
flow to cells and tissues
is reduced
Stepped Art
Fig. 8.5a, p.149
Useful References for Section 4
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 InfoTrac:
Babies Accept Hearts with All Blood
Types. UPI NewsTrack, April 5, 2005.
Section 5
Rh Blood Typing
Rh Blood Typing
Rh blood typing looks for an Rh marker.



Rh blood typing looks for the presence (Rh+)
or absence (Rh-) of antigen on red blood cells.
An Rh- person transfused with Rh+ blood will
produce antibodies to the Rh marker.
Rh Blood Typing

An Rh- mother who bears an Rh+ child can also
become sensitized to the Rh antigen;
secondary children may be at risk from
maternal antibodies.
•
•
In hemolytic disease of the newborn, too many
cells may be destroyed and the fetus dies.
Medical treatment (RhoGam) given to the mother
after the birth of the first Rh+ baby can inactivate the
Rh antibodies.
Animation: Rh Blood Type
and Pregnancy Complications
CLICK
TO PLAY
Rh Blood Typing
There are also many other markers on red
blood cells.



Hundreds of different blood cell markers are
known; most are widely scattered in the human
population.
To avoid problems with transfusions, blood
undergoes cross-matching to exclude
incompatible blood types from being used.
Useful References for Section 5
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 InfoTrac:
Rh Disease: It’s Still a Threat.
Contemporary OB/GYN, May 2004.
Section 6
New Frontiers of Blood
Typing
New Frontiers of Blood Typing
Blood + DNA: Investigating crimes and
identifying mom or dad.




Blood cell markers can be used to compare
evidence from crime scenes to samples taken
from possible perpetrators.
Because blood groups are determined by
genes, they are a useful source of information
about a person’s genetic heritage.
Blood typing can also be used to help
determine the identity of a child’s father or
mother.
New Frontiers of Blood Typing
For safety’s sake, some people bank their
own blood.



Even with screening, blood transfusions still
carry the risk of being incompatible or
potentially contaminated with infectious agents.
In autologous transfusions, individuals predonate blood to
themselves prior
to surgeries in case
transfusion is needed.
Figure 8.7
New Frontiers of Blood Typing
Blood substitutes must also avoid sparking
an immune response.



Blood substitutes have potential uses in
situations where it is not feasible to perfectly
match blood, such as in an ambulance or on
the battlefield.
To date, however, substitutes have
been difficult to manufacture;
OxygentTM is an oxygen carrier
that has currently reached the final
stages of clinical trials.
Useful References for Section 6
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 InfoTrac: Autologous
Blood Transfusion: A
Safer Way of Transfusion. GP, Feb. 24, 2006.
Section 7
Hemostasis and Blood
Clotting
Hemostasis and Blood Clotting
Hemostasis prevents blood loss.


Hemostasis is the process that stops bleeding
to prevent excess loss of blood.
•
•
•

Spasms of the smooth muscle in the damaged blood
vessel stop blood flow for a few minutes by
constriction of the vessel.
Platelets clump to plug the rupture; they then release
serotonin and other chemicals to prolong the spasm
and attract more platelets.
Finally, the blood coagulates to form the clot.
Hemostasis can only seal tears and punctures
that are relatively small.
Animation: Hemostasis
CLICK
TO PLAY
1
Injury to
blood vessel
Blood flow
2
3
Wall of vessel
contracts
Platelets stick
to collagen fibers
of damaged vessel
wall
Blood flow
decreases
Blood flow Platelet
decreases plug
4
More permanent
clot forms
Blood flow
ceases
Prothrombin
Damaged cells and
platelets release
substances that
activate clotting
factors
Prothrombin
activator
Ca2+ Fibrinogen
Thrombin
Ca2+
Fibrin threads
(clot)
Fig. 8.8, p.152
Hemostasis and Blood Clotting
Factors in blood are one trigger for blood
clotting.



In the intrinsic clotting mechanism, internal
damage activates a plasma protein (“factor X”)
that triggers the formation of thrombin.
Thrombin acts on fibrinogen to form insoluble
threads of fibrin that will entrap blood cells and
platelets to form a clot.
Hemostasis and Blood Clotting
Factors from damaged
tissue also can cause a
clot to form.


In the extrinsic clotting
mechanism, blood
clotting is triggered by the
release of substances
outside the blood itself
due to damage there; the
pathway is similar to the
intrinsic mechanism.
Figure 8.8
Hemostasis and Blood Clotting

Clots that form in unbroken vessels can be lifethreatening.
•
•

A clot that stays where it forms is called a thrombus;
one that breaks free and moves is called an
embolus.
A stroke occurs when an embolus blocks flow to
some part of the brain.
Hemophilia is a genetic disorder where clotting
factors are absent from the blood so it does not
clot properly.
Damage to skin
Epidermis
Dermis
Blood clot
Blood vessels
Neutrophils
defensive
WBCs)
Fig. 8.9, p.153
Scab
Regenerating
epithelium
Collagen
fiber
Blood
vessel
Collagen
fiber
Fig. 8.9, p.153
Useful References for Section 7
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 American Academy
of Family Physicians:
Hypercoagulation
 InfoTrac: Factor V Leiden as a Common
Genetic Risk Factor for Venous
Thromboembolism. Journal of Nursing
Scholarship, Spring 2006.
Section 8
Blood Disorders
Blood Disorders
Anemias are red blood cell disorders.



Anemias develop when red blood cells deliver
too little oxygen to the tissues.
Two types result from nutrient deficiencies:
•
•

In iron-deficiency anemia, red cells contain too little
hemoglobin, usually resulting from an iron-poor diet.
Pernicious anemia is caused by a deficiency of folic
acid or vitamin B12.
Aplastic anemia results from a destruction of
the red bone marrow and its stem cells.
Blood Disorders

Hemolytic anemias are
caused by the premature
destruction of red blood cells.
•
•
•
Sickle cell anemia, a genetic
disease, is one cause.
Malaria is a major cause of
hemolytic anemia and follows
infection by a protozoan
transmitted by mosquitoes.
In thalassemia, individuals produce abnormal
hemoglobin.
Figure 8.10
Fig. 8.10, p.154
Fig. 8.10, p.154
Blood Disorders
Carbon monoxide poisoning prevents
hemoglobin from binding oxygen.



Carbon monoxide (CO) is a colorless, odorless
gas present in auto exhaust fumes and smoke
from wood, coal, charcoal, and tobacco.
CO binds to hemoglobin 200 times more tightly
than oxygen, thus blocking oxygen transport to
tissues.
Blood Disorders
Mononucleosis and leukemias affect white
blood cells.



Infectious mononucleosis is caused by the
Epstein-Barr virus, which triggers
overproduction of lymphocytes.
Leukemias are very serious cancers in which
there is an overproduction of white blood cells
and destruction of bone marrow; chronic
myelogenous leukemia is one type.
Fig. 8.11, p.154
Blood Disorders

Other viral infections, such as HIV (the human
immunodeficiency virus), can also harm or
destroy white blood cells.
Toxins can destroy blood cells or poison the
blood in other ways.



Septicemia can occur when bacteria release
toxins into the blood; Staphylococcus aureus
(Staph A) is one important example.
Toxemia happens when metabolic poisons
accumulate in the body; toxemia can occur if
the kidneys do not adequately filter the blood
and remove these poisons.
Video: Global AIDS
 This
video clip is available in CNN Today
Videos for Biology, 2003, Volume VII.
Instructors, contact your local sales
representative to order this volume, while
supplies last.
Useful References for Section 8
The latest references for topics covered in this section can be found at
the book companion website. Log in to the book’s e-resources page at
www.thomsonedu.com to access InfoTrac articles.
 Leukemia
& Lymphoma Society
 National Heart, Lung, and Blood Institute:
Blood Diseases and Resources Information
 InfoTrac: When Mono Strikes. Nina M. Riccio.
Current Health 2, March 2000.
 InfoTrac: Anemia: That Run-Down Feeling.
Shiela Globus. Current Health 2, Mar. 1999.