Transcript What could have caused this? - Hicksville Public Schools / Homepage

Do Now Quiz
1. What are antigens and
where are they found?
2. What are antibodies and
where are they made?
3. Explain the relationship
between antigens and
antibodies.
LO: SWBAT describe how our body
becomes resistant to disease
DN: Quiz #2
HW: Read page 1034-1040, page
1053# 29,30,40
Quiz Friday
Bioterrorism
Today there is mounting concern
about the threat of a bioterrorist
Fatal hemorrhagic
attack using smallpox
-- sosmallpox
muchin
a twelve-year-old girl, 1970s,
concern that in
October
2001 theBangladesh.
A genetically
engineered strain
of smallpox
American government
decided
to
might produce unusual
order enoughsymptoms
vaccines
to
protect
such as these. Here,
every U.S. citizen.
the eyes are filled with blood,
and blood reputation,
blisters form in the
Smallpox has a fearsome
mouth
and in
inside
the body.
having killed more
people
history
than
How disease.
can we protect ourselves?
any other infectious
What is a vaccine?
Antigen
Weakened
Pathogen
Antibody
a weakened or dead form of a pathogen so it is
no longer harmful, but it still has the antigens
present.
These antigens trigger an immune response.
How was the first Vaccine
developed?
English physician Edward Jenner
developed an inoculation against
smallpox in 1796.
Armed with the knowledge that
milkmaids who had been exposed to
cowpox, a relatively mild affliction,
didn't come down with smallpox,
Jenner intentionally infected an eightyear-old boy with cowpox. Two months
later he infected the boy again, this time
with smallpox. As Jenner expected, the
child didn't come down with the disease
-- he was immune.
Vaccines depend on the “memory”
of the immune system.
First response:
slow and weak
Second Response
(to same pathogen):
Quicker and
stronger
** After the first response, the immune system
“remembers” specific pathogens by leaving behind
WBCs that protect the body for years (memory cells).
How do scientists make vaccines?
•
http://www.pbs.org/wgbh/nova/bioterror/v
accines.html
1) Obtain pathogen
2) Weaken/kill
pathogen
3) Inject altered
pathogen (vaccine)
into organism.
4) Body responds to
antigens by
5)
Some
WBCs
specific
for
making antibodies
this pathogen remain in the
& having WBCs
body to protect the organism
attack invader.
from future attacks.
What happens when you get
invaded by the real pathogen?
Memory cells (WBC
specific for that
pathogen) are
already present and
will multiply quickly
and destroy the
invader before it
has the chance to
cause the disease.
Memory
Cells
What is immunity?
The ability of a person who
once had a disease to be
protected from getting the
same disease again.
Immune response
Vaccine
Real Pathogen
First exposure
Second
exposure
Interval between
exposures
Antibody Concentration
Real Pathogen
Interval
between
exposures
Vaccine
First
exposure
Second
exposure
Time
Vaccines
Active vs. Passive immunity
Active Immunity
• Your body makes
antibodies to fight
pathogen
• Long lasting
• Ex: vaccine, getting sick
with the pathogen
• Passive Immunity
• You get antibodies from a
different organism- your
body doesn’t make the
antibodies
• Short lasting
• Ex: injection of
antibodies, mother to child
How are these two types of
immunity different?