Transcript The Immune System - Clark Pleasant Community School Corp

The Immune System
Anatomy and Physiology
Immune System
• Your body’s protection against pathogens
(disease causing agents)
• Two major categories of defense:
• Non-specific and specific
Immune System
• Non-specific defenses
are general, and will
work against any
pathogen
• Species resistance,
mechanical barriers,
chemical barriers,
inflammation,
phagocytosis
Immune System
• Specific defenses fight
off only one particular
pathogen
• Lymphocytes
specialize and become
T cells and B cells
• T cells activate B cells
B-cell Activation
B cells produce
antibodies; the single
most effective
protection
Antibody structure
• Y shaped
• Variable part fits only
one antigen
• Very specific
Antibodies on B cells
Immune System
• Antibodies are made
in response to a
specific antigen
• Takes a while to figure
out the exact shape to
fit the antigen
• Once made, memory
cells will be kept for
future exposures
Immune System
• Memory cells explain
why you don’t get the
same disease twice
• Some common
illnesses, such as cold
and flu, are really
different mutated
forms of the virus.
Each time takes a
different antibody
Immune System
• Vaccines: are killed or
weakened antigens
• They cause you to
make the antibodies
and memory cells
without you getting
sick
• They are ready if you
are ever exposed
Type of Immunity
• Active: You make the
antibodies in response
to an antigen
• Passive: Already
made antibodies are
given to you—mother
to baby; some
injections for illness
Type of Immunity
• Naturally acquired:
you came across the
pathogen naturally
(got sick)
• Artificially acquired:
a vaccine; you
stimulate the exposure
on purpose
Type of Immunity
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•
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Naturally acquired active immunity
Naturally acquired passive immunity
Artificially acquired active immunity
Artificially acquired passive immunity (does not
last long)
• Primary: first exposure (get sick, takes time to
make antibodies)
• Secondary: 2nd or more exposure (quick response
from memory cells)
What vaccines have you had?
•
•
•
•
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Hepatitis B
DPT
Polio
MMR
Hib
Pneumococcal