Download Bacteria Basics

BACTERIA BASICS
There
are two kingdoms of
bacteria:
Archaebacteria and Eubacteria
All
bacteria are unicellular
prokaryotes.
 Most
bacteria like a warm, dark, and moist
environment.
They are found almost everywhere:
-water
-air
-food
-soil
- inside the body
- skin
-on most objects
WHERE ARE BACTERIA
FOUND?
 Many
bacteria are so small that a million of
them, laid end-to-end, would measure no more
than about five centimeters (two inches).
 They
tend to multiply very rapidly under
favorable conditions, forming colonies of
millions or even billions of organisms within a
space as small as a drop of water.
BACTERIA
 How
quickly bacteria reproduce
depends on how desirable the
conditions are.
 Bacteria
can rapidly reproduce
themselves in warm, dark, and moist
conditions.
REPRODUCTION OF BACTERIA
 Some
can reproduce every 20 minutes
 (one
bacterium could be an ancestor to
one million bacteria in six hours)
REPRODUCTION OF BACTERIA
 Asexual
reproduction- reproduction of a
living thing from only one parent (only one
set of DNA)
 Examples:
binary fission, budding, or
regeneration
REPRODUCTION OF BACTERIA
 Bacteria
most commonly reproduce by binary
fission, the process by which a single cell
divides to produce two new cells.
 How?
 The
one main chromosome makes a copy of
itself. Then it divides into two.
REPRODUCTION OF BACTERIA
Reproduction of Bacteria
BINARY FISSION
Bacteria dividing
Completed
 endospore-
a thick walled, protective
structure that forms inside a bacterial cell
when conditions are unfavorable for survival
 It
acts like a force field. The bacterium can
stay dormant for a long period of time.
BACTERIA SURVIVAL
Bacteria Survival
Endospore-the
black section in
the middle
highly resistant structures
can withstand radiation, UV light, and
boiling at 120 degrees C for 15 minutes
 The
endospore encloses all the genetic
materials and some cytoplasm
 This
means bacteria can withstand boiling,
freezing, and extremely dry conditions
 The
endospore allows the bacteria to survive
for many years.
BACTERIA SURVIVAL
Helpful Bacteria
• Most bacteria are harmless or useful.
• Bacteria grow in the stomach
of a cow to break down grass
and hay.
•Some are used to make
antibiotics.
•Some bacteria help make insulin.
•Some are used to make industrial
chemicals.
Bacteria is used to treat sewage.
Organic waste is consumed by
the bacteria, used as nutrients
by the bacteria, and is no
longer present to produce
odors, sludge, pollution, or
unsightly mess.
HELPFUL BACTERIA
 Certain
kinds of bacteria are
also essential in the decay and
decomposition of waste
materials.
 Such
bacteria are known as decomposers.
 Decomposers
attack dead materials and break them
down into simpler forms that can be used as nutrients
by plants.
HELPFUL BACTERIA
 Remember:
most bacteria are harmless or useful.
(decomposers)
 Some
help you to digest food, make vitamins for you,
or prevent harmful bacteria from making you sick.
 Bacteria
are involved in the production of many foods
eaten by humans.
THE GOOD GUYS
 Bacteria
are used in making the
following foods:
 Cheese
 Yogurt
 Buttermilk
 Sour
cream
HELPFUL BACTERIA

Bacteria are used in making the following foods:

Apple cider

Sourdough bread
HELPFUL BACTERIA
 Bacteria
are used in making the
following foods:
 Olives
 Sauerkraut
 Pickles
 Vinegar
HELPFUL BACTERIA
 Bacteria
make possible the digestion of foods in
many kinds of animals.
 In
humans, bacteria known as Escherichia coli ( E.
coli ) occur everywhere in the digestive system,
aiding in the breakdown of many kinds of foods.
 Bacteria
are also responsible for the production of
vitamin K and certain B vitamins.
HELPFUL BACTERIA
Helpful Bacteria
E.coli on small intestines
21
The Bad Guys
 Some
bacteria cause food to
spoil.
 The
wastes they produce spoil the food.
 Since
bacteria reproduce better in warm
temperatures, you must keep food cold, that is why
we use refrigerators.
HARMFUL BACTERIA
3 ways to control bacteria in food:
1) Canning
2) Pasteurization
3) Dehydration
CONTROLLING BACTERIA
1)
Canning- the process of sealing
food in airtight cans or jars;
removes oxygen, destroys
enzymes, prevents the growth of
undesirable bacteria, yeasts, and
molds
CONTROLLING BACTERIA
2)
Pasteurization- the process of
heating a beverage or other food,
such as milk, in order to kill
microorganisms that could cause
disease, spoilage, or undesired
fermentation
CONTROLLING BACTERIA
3) Dehydration-
removing water from
food; bacteria can’t grow when
water is removed. (Remember:
Bacteria are living things. Water is
one of the needs of all living things.)
CONTROLLING
BACTERIA
 Human
tooth with accumulation of
bacterial plaque (smooth areas)
and calcified tartar (rough areas)
HARMFUL
BACTERIA
 some
bacteria cause diseases
 animals
can pass diseases to humans
communicable disease – a disease passed
from one organism to another
HARMFUL BACTERIA
 Diseases
may be passed from one
organism to another via:
 Air
 Touching
clothing, food, silverware, or a
toothbrush
 Drinking
water that contains bacteria
 Vaccines
help prevent some
bacterial infections.
 Antibiotics,
such as Amoxicillin,
help cure some bacterial
infections.
TREATMENTS
 Antibiotic
ointments and sprays kill bacteria
in cuts and scrapes
TREATMENTS FOR BACTERIAL
INFECTIONS
Antiseptic- chemicals that kill bacteria on
living things (OK to be on your body)
 means
– “against infection”
 Examples:
iodine, hydrogen peroxide,
alcohol, soap, mouthwash
CONTROLLING BACTERIA
ANTISEPTIC VS. DISINFECTANTS
Disinfectants- stronger chemicals
that destroy bacteria on objects or
nonliving things (NOT OK to put on/in
your body)
Examples: Lysol, bleach
CONTROLLING BACTERIA
ANTISEPTIC VS. DISINFECTANTS
Disease
Scientific Name
Contracted through
Food
_________________
Salmonella
Contaminated eggs,
poultry, meat
Escherichia coli (E coli)
Contaminated food,
especially undercooked
ground beef
__________ disease
Borrelia burgdorferi
bite of infected
blacklegged (or deer)
ticks
Tetanus
(____________)
Clostridium tetani
found in soil
Tuberculosis (____)
Mycobacterium
tuberculosis
breathing infected air
Strep ___________
Streptococcus
pyogenes
close contact with the
saliva or nasal secretions
from an infected
individual, typically in the
form of airborne
respiratory droplets
SOME BACTERIAL DISEASE
Food
poisoning
SOME BACTERIAL DISEASES
 Salmonella,
the name of a group of
bacteria, is one of the most common
causes of food poisoning in the United
States.
 Usually,
symptoms last 4-7 days and most
people get better without treatment.
 Salmonella
is killed by cooking and
pasteurization.
SALMONELLA
Sources
•Food: Contaminated eggs, poultry, meat,
unpasteurized milk or juice, cheese, contaminated
raw fruits and vegetables (alfalfa sprouts, melons),
spices, and nuts
•Animals and their environment: Particularly reptiles
(snakes, turtles, lizards), amphibians (frogs), birds
(baby chicks) and pet food and treats.
Symptoms
Diarrhea, fever, abdominal cramps, vomiting
Duration of Illness
4-7 days
SALMONELLA
 E.
coli is the name of a type of bacteria
that lives in your intestines and in the
intestines of animals.
 Although
most types of E. coli are
harmless, some types can make you
sick.
 The
worst type of E. coli, known as E. coli
O157:H7, causes bloody diarrhea and
can sometimes cause kidney failure and
even death.
ESCHERICHIA COLI (E COLI)
•Contaminated food, especially undercooked ground
beef, unpasteurized (raw) milk and juice, soft cheeses
made from raw milk, and raw fruits and vegetables (such
as sprouts)
•Contaminated water, including drinking untreated
water and swimming in contaminated water
•Animals and their environment: particularly cows, sheep,
and goats. If you don’t wash your hands carefully after
touching an animal or its environment, you could get an
E. coli infection
•Feces of infected people
Incubation Period 1-10 days
Sources
Symptoms
Severe diarrhea that is often bloody, severe abdominal
pain, and vomiting. Usually, little or no fever is present.
Symptoms of HUS include decreased urine production,
dark or tea-colored urine, and facial pallor.
Duration of Illness 5-10 days. Most people will be better in 6-8 days.
ESCHERICHIA COLI (E COLI)
 Lyme
disease is caused by the bacterium Borrelia
burgdorferi and is transmitted to humans through
the bite of infected blacklegged (or deer) ticks.
LYME DISEASE
 Tetanus
typically arises from a skin
wound that becomes
contaminated by a bacterium
called Clostridium tetani, which is
often found in soil.
TETANUS (LOCKJAW)

The disease has been called lockjaw since the
muscle spasms in the face and neck can lead to
the inability to open the mouth, and this is one of
the most common symptoms of tetanus.
TETANUS (LOCKJAW)
 In
the United States, most cases of tetanus follow a
contaminated cut or deep puncture injury, such as
a wound caused by stepping on a nail. Once the
bacteria are in the body, they produce a
neurotoxin. The toxin can travel throughout the
body via the bloodstream and lymph system. The
toxin interferes with the normal activity of nerves
throughout the body.
TETANUS (LOCKJAW)
 Tuberculosis
(TB) is an infection, primarily
in the lungs (a pneumonia), caused by
bacteria called Mycobacterium
tuberculosis. It is spread usually from
person to person by breathing infected
air during close contact.
TUBERCULOSIS
Streptococcus pyogenes causes Streptococcal
pharyngitis, streptococcal tonsillitis, or streptococcal
sore throat (known as strep throat) is a type of
pharyngitis. It affects the pharynx including the tonsils
and possibly the larynx.
STREP THROAT
 Strep
throat is a contagious illness that is spread
from person-to-person.
 Strep
throat symptoms generally include fever,
sore throat, swollen lymph nodes in the neck and
redness and swelling of the throat and tonsils.
White or yellow patches on the tonsils (signifying
pus) are also often present. Strep throat may
produce mild or severe symptoms.
STREP THROAT
 Strep
throat most commonly occurs between late
fall and early spring. It is more widespread during
the school year when groups of students are
present within an enclosed space.
 Though
strep throat is the most common bacterial
cause of sore throat, it is important to note that
most cases of sore throat are in fact due to a viral
infection (caused by a virus).
STREP THROAT
 It
is usually transmitted by close contact with the
saliva or nasal secretions from an infected
individual, typically in the form of airborne
respiratory droplets. For this reason, it is frequently
seen in situations where individuals are in close
proximity to each other, as in schools, college
campuses, military barracks, day care centers, and
family households.
STREP THROAT
Disease
Scientific Name
Contracted through
Food
poisoning
Salmonella
Contaminated eggs,
poultry, meat
Escherichia coli (E coli)
Contaminated food,
especially undercooked
ground beef
Lyme disease
Borrelia burgdorferi
bite of infected
blacklegged (or deer)
ticks
Tetanus
(Lockjaw)
Clostridium tetani
found in soil
Tuberculosis (TB)
Mycobacterium
tuberculosis
breathing infected air
Strep throat
Streptococcus
pyogenes
close contact with the
saliva or nasal secretions
from an infected
individual, typically in the
form of airborne
respiratory droplets
SOME BACTERIAL DISEASE
Bacteria
Bacteria are classified by shape into 3 groups:
Spiral
Rod-shaped
Round
3 Shapes of
Bacteria:
Leptospira interrogans –
(spiral-shaped)
Bacillus anthracis –
(rod-shaped)
Neisseria meningitidis
(round)
spirillum-one (singular)
spirulla –more than one (plural)
bacillus (singular)
bacilli (plural)
coccus (singular)
cocci (plural)
 But
some bacteria prefer cold
temperatures as low as freezing
(0°C or 32°F), and others require
very hot temperatures such as
those found in hot springs (50°C to
90°C or 120°F to 200°F).
ARCHAEBACTERIA
 The
most extreme conditions in which
bacteria have been found are around the
hydrothermal vents near the Galapagos
Islands.
 The
temperatures near these cracks in the
ocean floor is about 350°C (660°F), an
environment just right, apparently, for the
bacteria that live there.
ARCHAEBACTERIA