Fatty acids, proteins, bodily secretions,
and other substances with natural
attributes that help defend the body
against disease or infection. Such
substances may have a low pH, or serve
to breakdown or destabilize bacterial
cells.
Stomach Acid (lactobacillus)
The stomach uses
gastric acid with a pH2
to kill the microbes, but
some bacteria survive
by being inside food as it
goes through, others by
producing a cloud of
ammonia.
Ear Wax
Ear wax is slightly
acidic and will kill off
any bacteria that
cannot stand the
acidity that enters
through the ear
Salty tears
Kill the microbes
that are not able to
live with the salt
Mucus
sticky mucus in the
lungs traps microbes,
and then cilia sweep it
out of the lungs
Sweat
Posesses antibacterial
properties which have
hight levels ofacidity
Phagocytes
Phagocytes are the white blood
cells that protect the body by
ingesting harmful foreign particles,
bacteria, and dead or dying cells.
When there is an infection, phagocytes move to the
bacteria by sensing chemicals. When the bacteria touches
a phagocyte, they bind to its receptor and is eaten. The
phagocyte then moves parts of the killed bacteria back to
its surface. These parts are then shown to other cells of
the immune system. They then move to the body's lymph
node and show the bacterial parts to white blood cells
called lymphocytes. This action is important in getting
immunity.
Mechanical Barriers
A mechanical barrier in
the immune system is a
primary line of defense,
which physically impedes
the entry of foreign
particles that may harm
the body.
Ear drum
Stops water and
unwanted microbes
from entering the body
Nose hairs
Trap microorganisms
and prevents them from
entering the body
Ciliated lining in nose and lungs
Traps mucuse which traps the
microorganisms in the mucus
Skin
Prevents any
microorganisms to get
into your body. Acts as a
protective shield.
Specific Defenses
Antibody
Bacteria
Bacteria are tiny
single-cell
microorganisms,
usually a few
micrometers in length
that normally exist
together in millions.
Virus
A virus is a microscopic
organism consisting of genetic
material (RNA or DNA)
surrounded by a protein, fat,
or glycoprotein coat.
Antibodies are large
Y-shaped proteins. They
are recruited by the
immune system to
identify and neutralize
foreign objects like
bacteria and viruses.
Memory Cells
T Cells
Killer
Killer T-cells hunt down
and destroy cells that are
infected with germs or that
have become cancerous.
Helper
They are required for almost all
adaptive immune responses,
which activate killer t-cells,
Macrophage, and B cells to
secrete antibodies
B Cells
These lymphocytes, are designed
to provide immunity in the body
by developing antibodies when
they are exposed to antigens, that
invoke an immune response. B
cells are produced in the bone
marrow, which provides a steady
supply of them to the body. They
later mature into plasma B cells.
Plasma B cell
Once released into the
blood, these antibody
molecules bind to the
target antigen and
initiate its neutralization
or destruction.
Any small, long-lived lymphocyte that has
previously encountered a given antigen and that
on reexposure to the same antigen rapidly initiates
the immune response (memory T cell) or
proliferates and produces large amounts of
specific antibody (memory B cell) the agent of
lasting immunity.
Vaccinations
Getting a vaccine is something that will help
your body to protect itself from an infection in
the future. Vaccines help develop immunity by
imitating an infection, but this infection does
not cause illness. It does, however, cause the
immune system to develop the same response
as it does to a real infection so the body can
recognize and fight the vaccine in the future.
Dead Cell
These vaccines are
similar to DNA vaccines in
that they introduce DNA
from a harmful pathogen
into the body, triggering
the immune system to
produce antigens and
train itself to identify and
combat the disease.
Similar Cells
For these types of vaccines,
a weaker, asymptotic form
of the virus or bacteria is
introduced into the body.
Because it is weakened, the
pathogen will not spread
and cause sickness, but the
immune system will still
learn to recognize its
antigens and know to fight
in the future.