Transcript Living Things

Fighting Disease - Infectious Disease
How Pathogens Are Spread
Pathogens can spread through contact with an infected
person; soil, food, or water; a contaminated object; or an
infected animal.
Fighting Disease - Infectious Disease
Using Prior Knowledge
Before you read, look at the section headings and visuals to
see what this section is about. Then write what you know
about infectious diseases in a graphic organizer like the one
below. As you read, write what you learn.
1.
1.
What You Know
Bacteria and viruses can cause disease.
What You Learned
Pathogens spread through contact with an infected person,
animal, or object, or through contaminated soil, food, or drink.
Fighting Disease - The Body’s Defenses
The Immune System
The immune system
includes T cells and B
cells. The cells work
together to fight
infections.
Fighting Disease - The Body’s Defenses
Building Vocabulary
After you read the section, reread the paragraphs that
contain definitions of Key Terms. Use the information you
have learned to write a definition of each Key Term in your
own words.
Key Terms:
inflammatory
response
T cell
AIDS
antigen
phagocyte
HIV
immune response
B cell
lymphocyte
antibody
Examples:
When
body
cells of
areT damaged,
release
chemicals
Acquired
A
major
function
immunodeficiency
cells issyndrome,
to they
identify
or
pathogens
AIDS,
is and
a
that trigger
the inflammatory
is the
distinguish
disease
caused
one
kind
by aofvirus
pathogen
thatresponse,
attacks
from another.
thewhich
immune
body’s
system.second line of defense.
Antigens are molecules that the immune system
A
phagocyte
is
a as
white
blood
cell
that
engulfs
The
virus that
causes
AIDS
called
the
human
recognizes
either
part
of is
your
body
or
as coming
pathogens
and
destroys
them
by
breaking
them down.
immunodeficiency
virus, or HIV.
from outside your body.
If a pathogen infection is severe enough to cause a
The lymphocytes called B cells produce proteins that
fever, it triggers the body’s third line of defense—the
help destroy pathogens.
immune response.
The white
bloodare
cells
that antibodies.
distinguish between different
These
proteins
called
kinds of pathogens are called lymphocytes.