Download IV. Chemical Injury

IV. Chemical Injury and
V. Biological Injury
Chemical Injury
 Poison to the cell
 It is the dose and chemical composition
that make something poisonous
 Affects permeability of the cell membrane
 Tylenol can be poisonous in high
concentrations, lead is poisonous is small
amounts
 Vitamins
 Vitamin C—you can take as much as you
want (as is B)
 It is water soluble and passes through you
 Vitamin E—fat soluble and can be toxic
to the liver (as can A,D,E,K)
 Carcinogens: Chemicals that lead to
cancer (CA)
Biological Injury
 Parasites
 Bacteria
 Viruses
Parasites
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Parasites are a world-wide problem
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Malaria still kills many individuals
Parasites are not common in the USA
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Person probably out of the county
Malaria Parasite
©http://zap.intergate.ca/images/parasites%205%20giardia.jpg
Worms
©http://www.dherbs.com/store-images/parasite.jpg
Bacteria
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Bacterium: a tiny, primitive cell lacking a
nucleus
Bacteria are too large to get inside of our cells;
they usually cause disease through a release of
toxins
They take in glucose and release toxins which
make you sick
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Example: Bacteria in the back of your throat
What defenses do you have?
Mucus
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Protects every cell
Every day you come into contact with irritating
bacteria
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Mucus cells protect you from this
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Bacteria love 98.6*F
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Ideal for binary fission to occur (reproduction)
Bacteria may cause a number of diseases p. 10

Besides mucus cells, our bodies have another
defense mechanism
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Immune response

EX. You come down with strep throat; what
happens to your body?
Immune Cells Outline
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Leukocytes: the cells of the immune
system (also known as white blood
cells)
Two basic types of leukocytes:

1. Phagocytes: engulf and destroy foreign
bodies (common defense for bacterial
infections)
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Neutrophils

Monocytes

Macrophage
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2. Lymphocytes: cells that allow the body to
remember and recognize previous invaders and
help to destroy them (common defense for viral
infections)

Two types of lymphocytes:

T lymphocytes (from the thymus)

B lymphocytes (from bone marrow)
First Line of Defense Against
Bacteria

Neutrophils
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Most common type of white blood cells

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Main component of pus
“Watch dogs” of your immune system

Recognize, attack, and consume bacteria
through phagocytosis

Phagocytosis: engulfing of bacteria, cellular
debris, etc.
Phagocytosis

Contain numerous lysosomes filled with
digestive enzymes (nonspecific granules)
Neutrophil

Provide chemical signals called
LYMPHOKINES that carry messages between
the cells of the immune system

There are many types of lymphokines—they are
collectively known as interleukins
Neutrophil
©http://www3.umdnj.edu/histsweb/lab5/images/neutrophil.jpg
Neutrophil
©http://www.aamdsglossary.co.uk/i/c/1_neutrophil.jpg
Illustration of a Neutrophil
©http://www.dkimages.com/discover/previews/961/50311231.JPG
Neutrophil and a Bacterium
©http://www.chronicprostatitis.com/images/neutrophil.jpg
nd
2
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Line of Defense
Monocytes
Another type of white blood cell
Slower moving but much more lethal
By the time monocytes arrive, most of the
bacteria are already dead

If monocyte level is elevated on a blood test, the
infection has been going on for a while
Often elevated in chronic bacterial infections
 (most bacterial infections are acute)

Monocyte
©http://faculty.une.edu/com/abell/histo/monocyte.jpg
Monocyte
©http://users.path.ox.ac.uk/~cholt/monocyte.jpg
Illustration of a Monocyte
©http://www.dkimages.com/discover/previews/961/50311262.JPG
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Both neutrophils and monocytes are produced
in the bone marrow
Most effective production occurs when you are
sleeping
Why?
You are using the least amount of energy which
can then be used to produce wbc
What is a common problem when students go
to university?