Chapter 12

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Chapter 12
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Applied Learning Outcomes

• Use the terminology associated with the blood and
  lymphatic system
• Learn about the following
• Blood components
• Lymphatic system components
• Immune system function
• Mechanisms of immunization and vaccination
• Understand the aging and pathology of the
  lymphatic system

Chapter 12 The Lymphatic System and the Blood
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Overview
Blood is composed of plasma and formed
elements. Blood transports materials needed for
body homeostasis. There are three blood cell
types RBCs, WBCs, and platelets. The lymphatic
system regulates body fluids and the immune
system.
Chapter 12 The Lymphatic System and the Blood
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Overview

• Embryos
• lack blood until week 5 of development.
• Have pockets of special cells that start
  producing blood 2 weeks after the blood vessels
  form from the mesoderm.

• Plasma
• the fluid portion of the blood.
• Cells and other material are transported in
• Composed of 90 water, 7 protein, 1 minerals,
• and 2 other materials like gases, chemical
  signals,
• and nutrients.
• Primary gases are oxygen, carbon dioxide, and
  nitrogen
• Blood proteins assist with healing and immune
  system
• 55 of blood volume is plasma
• 45 is formed elements (Blood cells)

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Overview

• Three categories of blood cells
• erytrhocytes (red blood cells) RBC
• 2. leukocytes (white blood cells) WBC
• thrombocytes (platelets)
• Hematocrit (packed cell volume (PCV)
• the percentage of packed RBCs in a unit volume
  of
• whole blood
• Measure it by putting whole blood in a tube
  inside a
• centrifuge.
• Spin the blood until the RBCs collect as a
  pellet at the
• bottom of the tube.
• WBCs and Platelets can be found the same way.

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Overview

• Lymphatic system
• made up of tissues that produce, store, and carry
  lymphocytes throughout the body.
• responsible for fighting infection and
  controlling fluid
• levels in tissues.
• Includes bone marrow, specialized organs, and
  network of thin tubes
• Develops from mesoderm around week 5
• 5. Its full growth and function are not
  complete until after birth

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Blood Cells

• RBCs contain the protein hemoglobin.
• Blood type is another feature of RBCs.
• Classifications are types A, B, and D
• The A and B proteins make up the ABO blood group
  system
• The D protein is the Rh factor
• The five types of WBCs are neutrophils,
  lymphocytes, eosinophils, monocytes, and
  basophils.
• WBCs are categorized as granulocytic or
  agranulocytic.

Chapter 12 The Lymphatic System and the Blood
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Red Blood Cells
Lack a nucleus Immature RBC are called
reticulocytes RBCs live maximum of 120
days Contain hemoglobin that transports oxygen
and carbon dioxide Women average 4.8 million RBC/
cubic mm of blood Men average 5.4 million RBC/
cubic mm of blood Complete blood count (CBC) or
Full blood count (FBC) Series of tests that
examine components of the of blood Also known as
a Hemogram
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Red Blood Cells
Blood Type Way of categorizing RBCs according to
variation of proteins on the cell membrane
surface. The proteins A and B make up the ABO
Blood group system People with O type blood do
not have protein A or B on their cell membrane
surface The D protein is called the Rh factor.
You are Rh if you have the D protein Rh- people
lack the D protein.
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Blood Types
Makes Type antibodies accept
give to A against B A,
O A, AB B against A B, O B, AB
AB no antibodies A,B, AB, AB universal
against any blood and O
recipient O against A and B O
A,B, AB, universal O donor
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Blood Types
Rh have protein D on cell membrane. Rh- lack
protein D on cell membrane. Erythroblastosis
fetalis when a pregnant womans body produces
an immune response against Rh positive blood
from her developing fetus.
Only affects Rh- mothers. They are now given a
drug called Rhogam during and after pregnancy.
It causes the mothers body to destroy any
antibodies she has built up against Rh- blood.
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White Blood Cells

• Five types of WBCs
• Neutrophils most abundant (40-75)
• Lymphocytes (20-50)
• Eosinophils (5)
• Monocytes (1-5)
• Basophils (0.5)

Differential WBC count evaluates the percentage
of each WBC type. Important indicator of
infectious diseases Between 4000 to 11,000
WBC/cubic mm
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White Blood Cells

• Granulocytes (polymorphonuclear WBCs)
• Have granules in cytoplasm
• Produce specialized secretions for fighting
  infections
• Nucleus is polymorphic (unusual shape)
• Neutrophils, eosinophils, and basophils are
  examples.

• Agranulocytes (mononuclear WBCs)
• Lack visual granules
• Play role in the immune system
• Lymphocytes and monocytes are examples.
• Lymphocytes divided into two types
• B-lymphocytes and T-lymphocytes

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Platelets

• Not true cells
• Cell fragments
• Come from larger cells called Megakaryocytes
• Megakaryocytes are covered with many proteins
  that allow platelets to stick to a variety of
  materials.
• Stickiness helps reduce blood flow to a damaged
  area
• 250,000 to 500,000 platelets /cubic mm of blood

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Blood Cell Function
RBCs transport atmospheric gases throughout the
body oxygen from the lungs to the cells carbon
dioxide from the cells to the lungs
WBCs granulocytes produce secretions that kill
microorganisms lymphocytes are agranulocytes
that produce the bodys immune response
Chapter 12 The Lymphatic System and the Blood
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Blood Cell Function

• RBCs carry oxygen from the lungs to the body
  cells
• Oxygen attaches to the hemoglobin.
• Four oxygen molecules bind to one hemoglobin
  molecule.
• RBCs carry carbon dioxide from body cells to the
  lungs.
• Carried three ways in the blood
• 10 of the CO2 never enter the RBC- it is
  transported
• as a gas in the blood plasma
• 22 of CO2 released by tissues is carried by
  Hemoglobin
• Rest of CO2 is transported as a bicarbonate ion

RBCs stimulate formation of bicarbonate ions
using enzyme Carbonic anhydrase it converts
carbon dioxide and water into bicarbonate
ions. Important in maintaining blood pH.
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Blood Cell Function
WBCS -most of their functions are involved in
repairing the body and fighting infectious
disease. Granulocytes contain granules of
toxic chemicals that are released to kill
microorganisms and regulate reactions to foreign
materials in the body. Neutrophils- pass
through capillaries into infected tissues
they adhere to injured tissues and use
phagocytosis to engulf bacteria and
damaged cells. can secrete potent
antibiotics Eosinophils- produce secretions that
defend against large parasitic
organisms. Secretions kill protista and worms
increase in Eosinophils indicated
parasitic infection.
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Blood Cell Function
Granulocytes contain granules of toxic
chemicals that are released to kill
microorganisms and regulate reactions to foreign
materials in the body. Basophils are least
common WBC they secrete histamine stimulates
the immune response Overproduction of histamine
causes runny nose, sneezing, and watery
eyes Special basophil- Mast cell are responsible
for inflammation of tissues.
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Blood Cell Function
Agranulocytes Monocytes- once they leave bone
marrow develop into either circulating
monocytes tissue monocytes (macrophages) Circula
ting moncytes major role is to detect infectious
agents traveling in the blood Tissue macrophages
remove dead cells and attack microorganims that
are difficult to kill, such as fungi.
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Platelets
Involved in the Blood clotting process Carry out
a two-step process the platelets adhere to an
injured area followed by the activation of clot
formation. Intact vessels secrete a lipid called
prostacyclin which prevents platelet activation.
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• Damage to a blood vessel or body tissue produces
  a reaction
• The Clotting cascade
• tissue or blood vessel damaged
• Release collagen and clotting factors
• Causes platelets to adhere to damaged tissue and
  to each other
• Causes conversion of prothrombin into thrombin.
• Thrombin converts to a protein called fibrinogen
  into fibrin
• Fibrin forms sticky meshwork (beginning of clot)
• Sticky meshwork forms temporary barrier- prevents
  blood loss,
• Impedes passage of microorganisms
• Scab that forms is an example of a clot
• Clots not permanent, temporarily patch until it
  is repaired
• Plasminogen converted to plasmin-it is an enzyme
  that dissolves
• the clot.

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Blood Clotting Cascade
Cut in skin sticky platelets
clotting factors (prothrombin,
prothrombin activator, calcium)
causes the conversion to thrombin
fibrin forms a sticky
meshwork that fibrinogen adheres to
thrombocytes and other blood
components.
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Blood Cell Formation
Chapter 12 The Lymphatic System and the Blood
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Blood Cell Formation
All blood cells in adults are produced in the
bone marrow. In the embryo, the liver is
responsible for blood cell formation. All red
and white blood cells are derived from a type of
stem cell called hematopoietic or multipotent
stem cell. Hematopoietic cells can develop into
lymphoid stem cells or myeloid
progenitor Lymphoid progenitor cells give rise
to WBCs Myeloid progenitor cells give rise to
platelets, RBCs, WBCs
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Blood Cell Formation
Erythropoiesis is the process by which RBCs are
formed. RBCs mature in approximately 7 days and
live about 120 days. Aging RBCs are destroyed in
the liver and spleen. The digestive system then
removes the hemoglobin as a yellowish chemical
called bilirubin. WBCs live from 13 to 20 days.
Immature WBCs are released from bone marrow.
They are called bands or stabs. Then they are
destroyed by the lymphatic system.
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Lymphatic System

• Composed of lymphatic glands, lymph nodes, and
  lymph vessels
• Immune function provided by WBCs
• Immunity is either innate or acquired
• The body has a primary and a secondary immune
  response

Chapter 12 The Lymphatic System and the Blood
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Lymphatic System

• Structural components are
• Lymphatic vessels
• Lymph nodes (lymph glands)
• Spleen
• Thymus
• Tonsils
• WBCs
• Lymph

• Lymph vessels are thin ducts that carry lymph.
• They drain excess fluid that accumulates in
  tissue preventing edema (swelling)
• Lymph does a variety of jobs
• Removal of foreign bacteria and materials
• Transports fat from digestive system
• Moves mature lymphocytes (WBCs) to the blood

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Lymphatic System
Lymphatic trunk is a network of lymph vessels
that drains regions of the body. drains lymph
from larger areas of the body has collections of
small swollen regions of lymphatic tissue Tonsils
are one of a pair of clusters of lymphatic
tissue, located in the throat. Peyers
patches is another cluster of lymphatic tissue
located in the intestines
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Lymphatic System
Lymph nodes are complex collections of lymphatic
tissue covered by connective-tissue
capsules. Four components making them up Blood
vessels lymphatic sinuses lymphocytes filler
tissue (stroma) Hilum is region of the lymph node
where the blood vessel enters and
exit. Trabeculae is partitions that divide the
lymph node into regions. They contain B and T
lymphocytes. Macrophages are found in the
lymphatic sinuses.
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Lymphatic System
Spleen is divided into two functional
regions Red pulp - it is a storage area for
RBCs Also responsible for removing old or
damaged RBCs from circulation. White pulp -
region of lymphatic tissue contains B and T
lymphocytes Thymus gland located above the
heart larger during childhood begins to shrink
during puberty loses some of its functions as
you age.
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Immune Response
Is a complex array of anatomical structures and
cellular events that protects the body from
foreign chemicals called antigens. The immune
system uses two mechanisms to respond to
disease Innate immunity Aquired immunity
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Immune Response
Innate immunity nonspecific immunity skin,
mucus membranes, saliva, stomach acid, tears,
fever Interferons are a group of proteins that
cells produce following a viral
infection. They bind to other cells and inhibit
viral replication. Complements are a group of
plasma proteins that can be activated to destroy
microorganisms. Monocytes (WBCs) travel the
body destroying any material that
is not recognized as part of the body. Natural
killer (NK) cells are specialized T-lymphocytes
that secrete proteins that kill tumor cells and
microorganisms.
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Immunization and Vaccination
Natural immunity is the unintentional stimulation
of the immune system. Artificial immunity is the
use of therapy to stimulate the immune
system. Immunization is a medical strategy for
enhancing the bodys natural immune response.
Vaccines are immunizations that produce active
immunity. Active immunity is caused by exposure
to antigens. Passive immunity is produced by
providing the body with antibodies.
Chapter 12 The Lymphatic System and the Blood
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Wellness and Illness over the Life Span
Anemia is a common ailment of the blood that is
actually a group of various RBC disorders. Most
cases of anemia involve a decrease in the number
of RBCs. Genetic disorders can lead to the
production of abnormal blood cells. Blood
clotting is also subject to a variety of
disorders. WBCs are prone to deficiencies and
cancers. Most deficiencies are due to
malnutrition and exposure to hazardous chemicals.
Disorders of the lymphatic system affect its
ability to drain body fluids and carry out immune
functions.
Chapter 12 The Lymphatic System and the Blood
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Wellness and Illness over the Life Span

• Much of the aging of the blood and lymphatic
  system is due to changes in the digestive and
  endocrine systems.
• WBC function is likely to become abnormal with
  age.
• Immobility and weakening of the skeletal muscles
  is another feature of aging.

Chapter 12 The Lymphatic System and the Blood
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Summary
Plasma brings many nutrients to cells and carries
away wastes. RBCs carry oxygen to cells and
remove carbon dioxide. WBCs form part of the
immune system that protects the body from disease
and assists with injury repair. The lymphatic
system uses its own components and cells derived
from the blood to prevent and fight off
infections. Aging brings about changes to the
immune system that make people more susceptible
to infections and less likely to rapidly heal
injuries.
Chapter 12 The Lymphatic System and the Blood