Download Chapter 10 Microbiology

Microbiology
Microbiology

Study of very
small life forms


Some are harmful

Can’t see them
with the eye
Most are not
harmful


Used for
 Vitamins
 Antibiotics
 Some food
products


Yogurts
cheese etc.

Pathogens
 Disease causing
micro-organisms
Includes
 Bacteria,
 Viruses
 Protozoa
 Rickettsiae,
 Yeasts
 molds
Important people in Microbiology

Anton Van
Leeuwenhoek




Ground lenses
(glass) to magnify
things
Saw moving microorganisms
 In plaque
Wrote about
findings.
Father of
Microbiology.
Important people in Microbiology

Louis Pasteur





Experimented w/
fermentation
Proved bacteria
causes disease.
Proved heat killed
bacteria and spores
Work led to canned
food.
“Pasteurization”
 Heat product to
kill germs. (Milk,
beer)
Important people in Microbiology

Robert Koch



Proved specific
bacteria causes
specific diseases.
Etiologic agent
 Aka causitive
agent
Developed Koch’s
Postulates
 Steps to prove
that bacteria
caused disease.
Gram Stain

Helps ID the group
of bacteria

Developed by Dr.
Christian Gram
 Cells place on a
slide
 Dye added
 Rinse w/ iodine
 Dry
 Rinse w/ water
and acetone
alcohol
 Cell is observed.

Gram Positive


Cell will appear:
 Dark purple
Gram Negative

Cell will appear:
 To lose color
 Appear clear
 Appear “pink”
not purple
Gram Stain
Bacteria



Tiny
Single celled
Living organism



No chlorophyll
 molecule that
absorbs sunlight
Divide every 20
min.
 Warm Dark Moist
Killed w/
antibiotics
Spores

Spores

Bacteria that has


Sporulated or is
Sporulating




Resists





Coats itself in
Layers of protein
Ensures survival
Drying / Heat
Boiling
Most chemicals
radiation
Used in autoclave

“biological
monitor”
Bacteria and Oxygen

Aerobic


Needs O2 to grow
and live
 Most bacteria are
aerobic



Certain
Neisseria
Pseudomonas
aeruginosa
Staphylococcus,
or staph
Anaerobic


Die with O2
Can only live
without O2
 Gram-negative
anaerobes


Porphyromonas
(periodontitis)
Gram-positive
anaerobes

Peptostreptococ
cus (oral
infections)
Bacteria and Oxygen

Facultative anaerobic bacteria

Grow and live
With or Without O2
 They cause




Oral and dental infections.
Bacteremia
 bacteria in the blood stream
Endocarditis.
 Inflammation inside layer of the heart.
Bacteria Morphology

Cocci



Round
Circular
Spherical
 streptococcus

Bacilli


Rod
Straight
 Lactobacilli
Bacteria Morphology

Spirilla



Spiral
Spring
Corkscrew
 Helicobacter
pylori

Vibrous


C shaped
Curved (comma)
 Vibrio cholerae
Bacteria arrangements

Single Cell

Pairs

Clusters

Chains

Colonies
(lg. clusters)
Bacterial diseases







Tuberculosis
Diphtheria
Pertussis
Tetanus
Strep throat
Pneumonia
Rheumatic fever




Staph infection
Gangrene
Toxic shock
Venereal diseases



Aka (STD’s)
Chlamydia
Anthrax
Protozoa

Single celled
animal life





Causes;

Aka ameoba
Live in fluids:


Blood
Saliva
Intestines
Polluted water
 Pools
 ponds



Dysentery
 Severe diarrhea
Malaria
 Severe ‘flu’
Sleeping sickness
Periodontal disease
 Found in:


Plaque
Perio pockets
Yeasts and molds

Includes:





Bread yeast
Mushrooms
Bread molds
Causes


Form of plant life


No chlorophyll
Cannot be killed w/
antibiotics.
Used for
 Bacteria /
protozoa

Candidiasis
 Aka thrush
Fungal infection of:
 Mouth
 Vaginal area
Treatment

Anti-fungal drugs
Virus



Smallest
microorganism
Needs a host cell
to reproduce.
Most are anaerobic


Die w/ exposure to
air.
Not killed w/
antibiotics

Polio Virus
Examples of viral infections



Measles
Rubella
 (German
measles)
Mumps
 Infection of the
 Parotid salivary
glands







Polio
Chicken pox
Cold
Influenza (flu)
Hepititis
HIV
AIDS
Routes of exposure

Direct contact.



Indirect contact.


Sneezing into an open mouth.
Touching open sores.
Sneeze onto hand, touch door handle,
next person touches handle.
Inhalation

Aspirating / breathing in.
How the body resists diseases

1st line of defense.






Intact skin
Sneezing
Coughing
Vomiting
Diarrhea
2nd line of defense.


Circulatory
system
Wbc’s delivered
to area of
infection.

Inflammation

4 signs of
inflammation
 Erythema
(redness)
 Edema
(swelling)
 Heat
 Pain
How the body resists diseases

3rd line of defense

Antibodies
 Produce immunity from specific pathogens.



Disease causing microorganism
Antigen
 Pathogens that cause body to produce
antibodies.
Allergen
 An antigen that causes an over-reaction
 Can cause anaphylactic shock.
Immunity


A person/bodies ability to resist a
pathogen or disease.
Two kinds

Natural


Born w/ it.
Acquired

Have to get it.


Naturally
Artificially
Acquired immunity

Passive



Antibodies from
another person are
injected into you.
Immediate
Short term


6 weeks
Breast milk
provides some
passive immunity
to baby

Active

Natural acquired


Person gets a
disease, body
produces
antibodies, should
not get disease
again.
Artificial acquired

Immunization


Antigen is injected
Antibodies are
produced
Conclusion





Understanding the disease process
and how it affects the human body
is very important.
You are the “expert”!
Don’t ever diagnose!
When in doubt…ask questions.
Any questions?????????