Transcript Blood PPT

Honors A & P
Blood Unit
Functions of Blood
• Distribution
– Transporting digestive nutrients, oxygen,
wastes, hormones, etc.
• Regulation
– Fluid balance within the body tissues and
maintaining human body temperature.
• Protection
– Immune system (disease) and blood clotting
(loss of blood)
What is in Blood?
• Blood is a vascular connective tissue
• The three formed elements, or cells, in the blood
are: erythrocytes (red blood cells), leukocytes
(white blood cells), and thrombocytes (platelets).
• Plasma is the liquid portion of the blood, which is
~92% water. The other 8% are mainly proteins
as well as waste products, gases, and nutrients.
Composition of Blood / Hematocrit
• From a sample of
whole blood:
– Plasma makes up
55%.
– 45% are red blood
cells = hematocrit test
– <1% are white blood
cells and platelets
Blood Composition / Complete Blood
Count (CBC)
RBC’s = 4 – 6 million cells/mL
WBC’s = 5 – 11 thousand cells/mL
Platelets = 12 – 300 thousand cells/mL
Blood Volume & Characteristics
• On average, accounts for 8% of our
total body weight
– 5 to 6 liters of blood for males
– 4 to 5 liters of blood for females
• Under normal conditions, one’s
complete blood volume circulates
completely through the human body
every minute.
Erythrocytes / Red Blood Cells
• Biconcave shape,
flexible cells
• 7.5 x 2 micrometers
• Red Blood Cells
transport oxygen on
molecules called
Hemoglobin.
• Oxyhemoglobin vs.
Deoxyhemoglobin.
• Average lifespan is 120
days.
Blood Typing
• Researched why some blood
transfusions saved patients
while some caused death in
other patients
• Proposed that humans have
multiple classifications, or
types, of blood A, B, AB, O
• Won Nobel Prize in Medicine
in 1930 for establishment of
blood types.
Karl Landsteiner
Blood Typing – ABO System
• The A, B, O blood group
designates the “letter” to
one’s blood type.
• Blood type is determined
by which antigens (on
the RBC’s) are present.
• Antibodies (in the
plasma) against foreign
antigens are also
present.
• Blood type is genetically
determined and the ABO
antigens and antibodies
are present at birth.
Blood Typing – Rh System
• Rh factor determines the + or –
of your blood type.
• It is an antigen on RBC’s that
may (+) or may not (-) be
present at birth.
• Rh antibody will only be created
upon an exposure to foreign
antigen (not present at birth).
• Rh+ individual
– Has Rh antigen
– Will not develop the antibody
• Rh- individual
– Does not have the Rh antigen
– May develop the antibody upon
exposure
Erythroblastosis Fetalis
Agglutination Reaction Test
• Agglutination
reactions are a
clumping of
particles / cells
due to antigenantibody
complexes
forming
RBC Disorders
• Anemia’s – series of disorders of a
reduced ability to carry oxygen in the
blood (RBC count vs. Hemoglobin level)
• Polycythemia – increased RBC count that
leads to increased blood viscosity
(thickness)
Leukocytes / White Blood Cells
• Leukocytes are the mobile units of the body’s immune
system.
• They defend against the invasion of pathogens.
• Characteristics:
– They can leave the circulation and go to the sites of
invasion and tissue damage (Diapedisis)
– They chemically trail the presence of foreign antigens to
detect disease causing organisms.(Positive chemotaxis)
• 5-11 thousand/ml of blood normal.
Leukocyte Mobilization
Types of Leukocytes / Differential WBC Count
Granulocytes (1 day LS)
• Neutrophil
– Bacterial infections
– 60 – 70%
• Eosinophil
– Parasitic worm infections
– 2 – 4%
• Basophil
– Allergic response
(Histimines)
– <1%
Agranulocytes (1 mo 
several years LS)
• Lymphocytes
– Viral infections
– Trigger immune response
(production of antibodies)
– 20 – 25%
• Monocytes
– Macrophage cells
– 3 to 8%
Never let monkeys eat bananas!!!
Disease Transmission
• Pathogen is a disease causing organisms that may be
passed from host to host
– Direct Contact: kissing, sexual contact, spray from a
cough or sneeze
– Indirect Contact: shared object conveys the pathogen
(clothing, dishes, needles, etc.)
– Airborne: inhilation of a pathogen carried by the air
(carried in waste, viruses, bacterial spores)
– Vectors: an organisms acts as a carrier of the
disease (rodents, pests, etc.) usually transmitted
through a bite or sting
Immune System – Types of Immunity
• An immunity is the capability of the body to
resist harmful pathogens from invading.
1. Innate immunities are inborn (natural)
resistances to disease
2. Acquired immunity that is picked up over the
course of one’s lifetime.
Immune System: Innate Immunities
• Examples:
– Nonsuseptability: certain diseases only infect along certain
species lines (Pets – Humans)
– Physical and Chemical Barriers: skin, enzymes, acidity act to
limit disease
– Genetic resistance: certain diseases are more / less common
based upon genetic racial differences (Tuberculosis)
– Nutrition: good nutrition and health leads to a healthy immune
system, more resistance (80% of infectious disease is limited to
20% of the human population)
– Body temperature: Constant body temperature (100.3 degrees
F) prevents invasion from some pathogens
Immune System: Acquired (Induced)
Immunities
• Active vs. Passive:
– Active immunities take a while to develop in the body, but last a long
time.
– Active Immunities develop by an individual generating antibodies for
themselves.
– Passive immunities are immediate acting, but are short lived.
– Passive Immunities are generated elsewhere and acquired by an
individual.
• Natural vs. Artificial:
– Natural forms have the immunity develop in a natural manner.
– Artificial forms have the immunity develop in an artificial manner and
introduced into the body.
Acquired (Induced) Immunity Diagram
Examples are listed at the bottom of each of the 4 cells …
Immune System – Immune Response
• The immune response is how your body
recognizes and defends itself from
pathogens that have entered the body.
1. The non-specific immune response is a general
response of the body upon invasion of a
pathogen, regardless of the type of pathogen.
2. The specific immune response is a targeted
attack made by the immune system in response
to a particular pathogen.
Immune System – Non Specific Immune
Response
• Examples:
– Upgrade of chemical barriers: increase of the amount
of tears, saliva, acids, mucus, etc. to isolate the
pathogen that has entered
– Mobilization of Phagocytes: Macrophages and other
WBC’s migrate to infection site to engulf pathogen for
the purpose of recognition
– Fever / Inflammation: WBC’s release pyrogens
(trigger an increased body temperature to weaken a
pathogen) and histamines (causing swelling and
inflammation
Immune System - Specific Immune
response
• T – Lymphocytes trigger the overall activity of
the immune system upon recognition
– T4 (helper) Cells: increases the activity of the specific
immune system
– T8 (cytotoxic) Cells: attack and destroy infected cells
through apoptosis
– Ts (surpressor) Cells: reduce the activity level of the
specific immune system upon control of the pathogen
Immune System – Specific Immune
Response
• B – Lymphocytes upon recognition differentiate
into plasma cells which are responsible for the
production of antibodies.
– Antibodies may then agglutinate (cause clumping of
cells) or neutralize (surround and immobilize) a
pathogen
– Macrophage cells then engulf the agglutinated or
neutralized pathogens and lyse themselves (and the
engulfed pathogens as well).
Specific Immune Response
B-Lymphocytes
T- Lymphocytes
Recognition
T4
2000 / second
T8
WBC Disorders
• Leukocytosis (increase WBC count) and
Leukopenia (decrease WBC count) are
symptoms that other disorders are
occurring in the body
• Leukemia – cancer of the WBC
• HIV – viral invasion of T –lymphocytes
• Autoimmune diseases – immune system
loses the ability to distinguish foreign from
self antigens
Platelets
• They remain
functional for about
10 days.
• 1/3 stored in spleen
• 200 - 250
thousand/ml of
blood
• They begin the
clotting process
upon an injury.
Hemostasis
• The series of events
that stops the flow of
blood from an injury.
• Release of Tissue
Factor
– Injury tissue releases
tissue factor, exposes
collagen fibers
– Platelets disintegrate
and release tissue
factor
Hemostasis
•
Vasoconstriction:
arteries leading to
the damaged area
constrict to limit
blood flow / loss
Hemostasis
•
Platelet Plug
Formation – tissue
factor causes platelets
become “sticky”, they
cling to one another
and the inner lining of
a damaged blood
vessel.
Hemostasis
•
Coagulation –
formation of a blood
clot.
–
–
–
Formation of
Thromboplastin
Prothrombin +
Thromboplastin 
Thrombin
Fibrinogen +
Thrombin  Fibrin
Hemostasis
Platelet Disorders
• Thrombus: clot that develops and persists in an
unbroken blood vessel
– May block circulation, leading to tissue death
– Embolus: a thrombus freely floating in the blood
stream
• Pulmonary emboli impair the ability of the body to obtain
oxygen / Cerebral emboli can cause strokes / Cardiac emboli
can cause heart attack /
Platelet Disorders
• Hemophilia- recessive genetic disorder
that reduces levels of clotting factors
• Prolonged episodes of bleeding 
hematoma formation
Hematopoisis: Formation of Blood
Cells (Formed Elements)
• Takes place in the red bone marrow
• Very active in the skull, ribs, vertebrae,
pelvis, femur and humerus.
• All formed elements originate from the
hemocytoblast (adult blood forming stem
cell)
• Cells then develop in the marrow as
precursor cells – when fully mature, are
released into the blood stream.
Hematopoisis - Control
• RBC’s: Due to oxygen deficiency, the kidneys and
liver release Erythropoitin (EPO) which triggers
RBC formation.
• Platelets: Due to platelet deficiency, the kidneys
and liver release Thrombopoitin (TPO), which
triggers platelet production
• WBC’s: Upon recognition of an invading pathogen,
WBC’s secrete Interleukins and Colony Stimulating
Factors (CSF’s) to trigger additional WBC
production.
Red Bone Marrow
– Precursor Cells
Blood Stream
– Mature Formed
Elements