Transcript Viruses & Bacteria

BACTERIA &
VIRUSES
MICROBIOLOGY
Is the basic science that explores microscopic
organisms including viruses, bacteria, protozoa,
parasites, and some fungi and algae.
 The organism lack tissue differentiation and are
unicellular, and exhibit diversity of form and
size.
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CHARACTERISTICS OF ORGANISMS
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All living things are composed of cells
All living things perform certain chemical
processes such as growth and digestion
All living things can reproduce
All living things either make their own
nutrients or ingest nutrients from the
environment
All living things respond to stimuli such as
light and touch
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Viruses, bacteria, fungi, and parasites may infect
the human body and interfere with normal body
functions.
A
WHAT ARE VIRUSES?
virus is a non-cellular particle
made up of genetic material and
protein that can invade living
cells and reproduce.
 A person can catch a cold many
times because there are many
varieties of cold virus that cause
similar symptoms
VIRUSES
Are not considered to be alive
but they affect living things.
 With the ability to reproduce,
viruses lack nearly every
characteristic of life
 Need a host cell
 Not composed of cells
 Do not respond to stimuli
 Do not use energy for growth
and development
 Need electron microscope to
see
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TYPES OF VIRUSES
AIDS
 Lyme disease
 Bacterial meningitis
 Leprosy
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DISEASE
 Any
change that disrupts the normal function
of one or more body systems.
 Noninfectious
diseases: Diseases caused by
exposure to certain chemicals or traits that
are inherited.
 Infectious
diseases: Diseases caused by a
pathogen (any microbe that causes disease.)
DISEASES CAUSED BY VIRUSES
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Cause disease by either damaging
or killing cells
First attaches itself to a healthy
cell and then injects its DNA or
RNA into cell
Then replicates once inside
infected cell
No Cure, just prevention with
vaccine.
Vaccines: a substance introduced
into the body to stimulate the
production of chemicals that
destroy specific viruses or
bacteria..
HOW INFECTIOUS DISEASE SPREAD

Infectious disease can be spread through:
1. contact with an infected person
ex: Influenza (V)
2. contact with a contaminated object
ex: Athleteis foot (F) or Influenza (V)
3. contact with an infected animal
ex: Lyme Disease (B): Bite from infected tick
contact with an environmental source.
BACTERIA
Are small organims constiting of one cell that
lack chlorophyll
 Except for viruses they are the smallest living
things on earth
 Bacteira are found everywhere, in the air, soil.
Water, and inside of your body and skin.
 They multipy very rapidly and from colonies of
millions or even billions witin a space as small as
a drop of water.
 Classified 4 ways (spherical, rodlike, spiral, or
corkscrew.
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DISEASES CAUSED BY BACTERIA
Use antibiotics to cure bacterial infections
 Antibiotics or a chemical that can kill
bacteria without harming a person’s cell
 Bacteria can develop a resistance to
antibiotic and will no longer kill
 This is what happens when you do not take
medicine completely
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VECTORS HELP SPREAD DISEASE
Are mechnaims (other
then people) that
spread disease
without getting itself
sick.
 Rats, ticks,
mosquitios, and soil
are examples.
 An infectious disease
is one that can be
passed from one
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DISEASES CAUSES BY PROTISTS
the protists that cause
each of these diseases
are caused by
parasites
 Parasite is an
organism that takes
nourishment or
habitat from another
organism
 Most cases do not kill
the host
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Examples
 Dysentery
 Malaria *
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EPIDEMIC
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Is an outbreak of a
disease that affects a
disproportionately
large number of
individuals within a
population,
community, or region
at the same time
PANDEMIC
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Is an epidemic of an
infectious disease that
is spreading through
human populations
across a large region,
continent,, or even
worldwide.