Download Latin Root Word: archeo

Opening Activity
Latin Root Word: archeo –
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Food poisoning
Bacterial Infection
Acne
Cavities
Body Odor
Antibiotics
Break down food in our digestive system
Intro To Bacteria
I. Basic Bacteria Facts:
•  Microscopic/unicellular
•  Prokaryotic
0.25
µm
Classification of Bacteria: Kingdom
Archaebacteria:
a)  More ancient than eubacteria
b)  Peptidoglycan absent in cell walls
III. Major Phyla of Bacteria:
1) Kingdom Archaebacteria:
a)  Methanogens live only
in anaerobic conditions
like swamps and sewage.
b)  Halophiles salt-loving
c)  Thermoacidophiles
live in acidic and high
temp. environments like
hot springs and volcanic
vents.
II. Classifications of Bacteria:
1)  Kingdom Eubacteria:
a)  Germs; account for most bacteria
b)  Can be divided into 12 phyla
c)  Cell walls contain peptidoglycan
Shapes of Eubacteria:
1. bacilli rod-shaped
2. cocci sphere-shaped
*streptococcichain
*staphylococcigrape-like clusters
3. Spirilla spiral-shaped
Eubacteria shapes cont.
streptococcichain
staphylococcigrape-like clusters
Eubacteria
•  Heterotrophs
•  Photosynthetic autotrophs
•  Chemosynthetic autotrophs
Eubacteria - Heterotrophs
•  Found everywhere
•  Parasites: live off of other
organisms
•  Saprobes: live off of dead
organisms or waste (recyclers)
•  Live symbiotically in the guts of
animals or elsewhere in the bodies
Photosynthetic Autotrophs
•  Photosynthetic: make their own food
from light
•  Cyanobacteria – blue-green
•  Slimy stuff in ponds, streams, moist
areas
•  Cyanobacteria were the first
organisms to do modern
photosynthesis and they made the first
oxygen in the earth’s atmosphere
Eubacteria: Chemosynthetic
Autotrophs
•  Get energy by breaking down
inorganic substances like sulfur
and nitrogen
•  Make nitrogen in the air usable
for plants – nitrogen fixing
bacteria in roots of legumes
III. Major Phyla of Bacteria:
1)  Kingdom Eubacteria:
a)  Cyanobacteria
(ex. blue-green algae)
b)  Spirochetes: spiral shaped
(causes syphilis)
c)  Gram-positive bacteria
(ex. Bacteria that cause
strep; change milk to
yogurt; produce antibiotics)
d)  Proteobacteria
(ex. E. coli; nitrogen-fixing
bacteria)
Most Bacteria reproduce by one
of 2 means:
1. Asexually
– Also known as
binary fission in
which the
chromosome
replicates and then
the cell divides
– This produces 2
identical cells
2. Sexual Reproduction
– Also known as conjugation in
which genetic material is
exchanged through cell-to-cell
contact. One cell passes DNA to
another.
– This increases the genetic
diversity of bacteria
IV. Gram Stain:
a) 
Laboratory technique used to group Eubacteria into two categories.
b) 
Gram-positive eubacteria appear purple because of thicker layer of
peptidoglycan.
c) 
Gram-negative eubacteria appear pink because of thinner layer of
peptidoglycan.
I. Bacteria and Disease:
A. 
Pathology: scientific study of disease
B. 
Pathogens: bacteria that cause disease
C. Famous Bacterial Diseases:
Type of Disease
Botulism
Cholera
Tooth Decay
Gonorrhea
Lyme Disease
Rocky Mountain
Spotted Fever
Salmonella
Strep throat
Tetanus
Tuberculosis
Areas Affected
nerves
intestines
teeth
Urethra/ fal.tubes
Skin, joints, heart
Blood, skin
Mode of Transmission
intestines
Respiratory tract
nerves
Lungs, bones, etc
Contaminated food
Sneezing/coughing
Contaminated wounds
coughing
Improper preserved foods
Contaminated water
Bacteria in mouth
Sexual contact
Tick bite
Tick bite
D. Ways Bacteria Cause Disease:
1.  Produce exotoxins (toxins made of protein and
produced by Gram-positive bacteria).
2.  Produce endotoxins (toxins made of
carbohydrates and lipids and produced by
Gram-negative bacteria; released when
bacteria die).
3.  Destroy body tissues by secreting digestive
enzymes.
Opening Activity: 3.2
•  Latin Root Word: immun-
Routes of Bacterial Infection
•  Respiratory tract
•  Gastrointestinal Tract
•  Genitourinary tract
•  Unnatural routes opened up
by breaks in mucous
membranes or skin
Bacterial Evasion of Host Defense
Mechanism
•  Four Steps in Bacterial Infection
–  Attachment to host cells
–  Proliferation
–  Invasion of host tissue
–  Toxin-induced damage to host cell
Immune system
•  Two parts
–  Innate immune
system (non-specific)
–  Adaptive immune
system (specific)
Nonspecific host resistance
mechanisms
  Innate Immune system
  Immediate response
  physical barriers such as skin
  chemicals in the blood
  immune system cells that attack foreign cells in
the body.
Specific host Immune Response
to Bacteria
  Adaptive Immunity
  immune cells (antibodies) specifically designed to
attack that foreign cell
  includes a "memory" that makes future responses
against a specific foreign cell more efficient.
Contribution of the Immune
Response to Bacterial Pathogenesis
•  Disease can also be caused by the immune
response to the pathogen.
•  Pathogen-stimulated overproduction of
cytokines can lead to symptoms of bacterial
septic shock, and toxic shock syndrome.
II. Antibiotics:
A.  Drugs that combat bacteria by interfering
with cellular functions.
B.  Because humans overuse antibiotics,
bacteria have built a resistance to those
antibiotics. This is done through bacteria
reproduction AND genetic recombination.
Penicillin, an antibiotic, comes from molds of the
genus Penicillium Notice the area of inhibition around
the Penicillium.
C. Common Antibiotics
Antibiotic
Penicillin
Mechanism of Action
Inhibits cell-wall
synthesis
Ampicillin
Same as above
Bacitracin
Same as above
Cephalosporin Same as above
Tetracycline Inhibits protein
synthesis
Streptomycin Same as above
Sulfa Drug
Inhibits cell metabolism
Rifampin
Inhibits RNA synthesis
Quinolines
Inhibits DNA synthesis
Target Bacteria
Gram-Positive
Broad spectrum
G.P.
G. P.
Broad Spectrum
G.N.
meningitis
G.P. AND G.N.
Urinary tract
Are all bacteria pathogens?
•  No, most are harmless
•  Some are even helpful
–  Examples of helpful bacteria:
•  Lactobacillus: makes cheese, yogurt, &
buttermilk and produces vitamins in your
intestine
•  Leuconostoc: makes pickles & sauerkraut
•  Pediococcus: makes pepperoni, salami, &
summer sausage
USDA NIFSI Food Safety in the Classroom©
University of Tennessee, Knoxville 2006
A Closer Look – Helpful Bacteria
www.bioweb.usu.edu
Pediococcus - used in
production of fermented meats
Lactobacillus casei – found in human
intestines and mouth to improve digestion
Leuconostoc cremoris – used in
the production of buttermilk and
USDA NIFSI Food Safety in the Classroom©
sour cream
University of Tennessee, Knoxville 2006
Lactobacillus bulgaricus –
used in the production of yogurt
Helpful Bacteria
• Decomposers help recycle nutrients into the soil for other organisms to
grow
• Bacteria grow in the stomach of a cow to break down grass and hay
• Most are used to make antibiotics
• Some bacteria help make insulin
• Used to make industrial chemicals
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Helpful Bacteria
• 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.
• foods like yogurt, cottage & Swiss cheese, sour cream,
buttermilk are made from bacteria that grows in milk
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Controlling Bacteria
3 ways to control bacteria:
1) Canning- the process of sealing food in airtight cans or jars after
killing bacteria
• endospores are killed during this process
2) Pasteurization- process of heating milk to kill harmful bacteria
3) Dehydration- removing water from food
• Bacteria can’t grow when H2O is removed
• example: uncooked noodles & cold cereal
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Controlling Bacteria
Antiseptic vs. Disinfectants
Antiseptic- chemicals that kill bacteria on living things
• means – “against infection”
Examples: iodine, hydrogen peroxide, alcohol, soap, mouthwash
Disinfectants- stronger chemicals that destroy bacteria on objects
or nonliving things
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Drawing
Bacterial Structure
•  Cell Wall - outermost
structure of the cell.
•  Made up of a substance
called peptidoglycan
Bacterial Structure Continued
•  Capsule: This is a layer of
slime secreted over the cell
wall of the bacterium.
•  The capsule provides
protection
•  Most pathogenic bacteria are
encapsulated.
Bacterial Structure Continued
•  Flagella - whip - like
structures that propel the
bacteria
I. Common Structures/Functions of Bacteria:
Structure
Cell Wall
Outer Membrane
Cell Membrane
Cytoplasm
Chromosome
Plasmid
Capsule and slime
layer
Endospore
Pili
Flagellum
Function
Protects cell; gives it shape
Only in G.N.; protects against antibiotics
Important in cell respiration
Contains DNA/ribosomes
Carries genetic info.; single loop of DNA
Carries extra genes from genetic recom.
Protects cell; helps attach to other
surfaces (glycocalyx)
Only in G.P.; survival in harsh conditions
Helps attach to other surfaces
Cell movement
3. Spore Formation
•  When living conditions become
unfavorable, some bacteria can form
dehydrated cells known as endospores
•  Endospores have thick walls and can
resist heat, drought and radiation and
thus they can survive harsh conditions
Endospore
•  When
conditions
improve, the
spore will
germinate and
bacteria will
grow again
III. Bacteria in the Environment:
Type
Environment
Obligate Anaerobes
CANNOT live with oxygen
Facultative Anaerobes
Can live WITH or
WITHOUT oxygen
Obligate Aerobes
CANNOT live without
oxygen
“Thermophilic”
Grow best in HIGH
temperatures
Opening Activity
•  Greek Root Word: anti-