Download Viruses and Bacteria

VIRUSES AND BACTERIA
Monday
PRE-TEST
Please be
quiet while
taking the
quiz!
BACTERIA &
VIRUSES
BACTERIA ARE ALIVE!
 What does it mean to be
alive?
 They reproduce (make more of
themselves)
 They need to eat
 They are prokaryotic cells
USDA NIFSI Food Safety in the Classroom©
University of Tennessee, Knoxville 2006
WHAT ARE VIRUSES?
A virus is a non-cellular
particle made up of genetic
material and protein that
can invade living cells and
reproduce.
HOW DO BACTERIA REPRODUCE?
 Grow in number not in size
 Humans grow in size from child to adult
but bacteria do not
 Divide in half
 THEY GROW EXPONENTIALLY!!!!
USDA NIFSI Food Safety in the Classroom©
University of Tennessee, Knoxville 2006
BINARY FISSION
HOW ARE BACTERIA
AND VIRUSES RELATED
TO DISEASE?
BACTERIA AND VIRUSES
CAUSE DISEASE!
DISEASES
BACTERIA
 Anthrax
 Lyme Disease
 Leprosy
 Bacterial Meningitis
 Strep Throat
 Tuberculosis
 Many more…
VIRUSES
 Influenza
 West Nile Virus
 Common Cold
 AIDS/HIV
 Chicken Pox
 Ebola
 ZIKA
 Many more…
MAKE YOUR OWN AGAR
PLATES
Work with lab
partner
Please read
procedure
AGAR PLATES
 Please record our hypothesis before beginning
 4 quadrants(label on your handout and
plates. Please also write your name and
period # ALONG THE EDGE)
1. Partner 1 cheek sample
2. Partner 2 finger sample
3. Partner 1’s choice for classroom sample
4. Partner 2’s choice for classroom sample
Upon gathering your samples, you will tape
Your plate shut and it may NEVER be opened
A gain. It is considered a biohazard!
WHAT DO YOU THINK
YOU’LL SEE?
WHAT ARE SOME OF THE
AREAS YOU SAMPLED?
WHAT IS BACTERIA?
EXIT SLIP
DEFINITONS
Microbe is a term for tiny creatures
that individually are too small to be
seen with the unaided eye.
includes bacteria, archaea , fungi
and protists.
Bacteria are:
•Unicellular
•Prokaryotic…which means?
Fact: Each square centimeter of your skin
averages about 100,000 bacteria. A single
teaspoon of topsoil contains more than a
billion (1,000,000,000) bacteria.
GOT SOAP?
The best prevention against
infectious disease is…
Handwashing!
Water, soap and friction
wash away…
Bacteria
 Viruses
 Parasites
 Yeasts
 Fungi

that can cause disease.
Trivia Time!!!
How many diseases can be
spread by not washing your
hands?
Over 200!
How many people stop to
wash their hands after
using the bathroom?
Only 1 in 3!!!
(or 33%)
How long should you scrub
your hands when washing?
10 – 20
seconds
Germ Killing Techniques
1.
2.
3.
4.
5.
6.
Wet hands with water.
Apply soap.
Scrub all surfaces of hands for 10 to 20
seconds.
Rinse thoroughly under running water.
Dry hands completely with a paper towel.
Turn off water with the paper towel.
When Should You Wash?
After using the restroom
Before and after eating
Before applying make-up, inserting
contacts, using eye drops, etc.
After petting animals
Before and after food preparation
After taking care of sick people
After handling money
When hands feel dirty
What about in the classroom?
Why Make Such A Big Deal
Out Of Handwashing?




These organisms that cannot be seen with the
naked eye are powerful and given the
opportunity, they will infect you.
They can make you sick for the day, for months,
or even cause death.
They are not concerned about who they infect so
everyone is at risk. The young, elderly and those
with a compromised immune system are
particularly vulnerable.
Even if you do not get sick from some germs you
pick up, the person you unknowingly spread it to
could have serious complications.
Time for a few definitions…
Infectious Diseases
Diseases caused by germs
that are passed personto-person.
Germs or Microorganisms

Microscopic, one-celled
living organisms.
Bacteria and viruses are
both considered
microorganisms.
Germs Are Everywhere!
There must be other ways to
protect myself in addition to
handwashing…
The germs that cause the
common cold can live on a tissue
for how many days and remain
infectious?
7 – 10 days
Clean vs. Dirty hands

Culture of Clean
Hands

Culture of dirty
hands
Be on the lookout for germs!
And remember…
No Matter Who You Are…
No Matter What You Do…
WASH YOUR HANDS!
EXIT SLIP
HOW CAN YOU GET
SICK FROM YOUR
HANDS?
VIRUSES AND
BACTERIA
wednesday
Doesn’t belong to any
kingdom
-It’s not a plant or an
animal.
-It’s not a fungi, protist, or
bacteria.
A virus is an infectious agent made up of
nucleic acid (DNA or RNA) wrapped in a
protein coat called a capsid.
Viruses have no nucleus, no organelles, no
cytoplasm or cell membrane—Non-cellular
This is why it does NOT belong to any kingdom.
vs
1. Bacteriophage—viruses that infect bacteria
Capsid (protein coat)
– inside contains either
RNA or DNA
2. Flu (influenza), HIV
DNA or RNA
Surface
Marker
Capsid (protein coat)
Common Virus Shapes:
43
Certain viruses can only attack
certain cell types. They are said to
be specific.
Example:
Surface
The rabies
Markers
virus only
attacks brain
or nervous
Receptor
cells.
Viru
s
Sites
It’s like the pieces of a puzzle.
The ends have to match up so
only certain pieces fit.
Cell
A virus recognizes cells it can infect by matching
its surface marker with a receptor site on a cell.
Virus
Surface
Markers
Receptor
Sites
Cell
Structure
Reproduction
Genetic Material
Growth and
Developmen
t
Obtain and
Use Energy
Response
to
Environmen
t
Change over time
RNA or DNA core
(center), protein coat
(capsid)
Cell membrane,
cytoplasm, genetic
material, organelles
Copies itself only inside
host cell--REPLICATION
Asexual or Sexual
DNA or RNA
DNA and RNA
NO
YES—Multicellular Organisms
NO
YES
NO
YES
NO
YES
How are diseases caused by
viruses?
 They 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.
 What are vaccines?
 a substance introduced into the body to
stimulate the production of chemicals
that destroy specific viruses or bacteria..
Movie time
Ebola Crisis
How does ebola spread in the
movie? Is it a bacteria or
virus?
EXIT SLIP
BACTERIA AND
VIRUSES
Thursday
HOW DOES A DISEASE
SPREAD?
Epidemiology
• Epi = upon
• Demos = people
• Ology = science
• Epidemiology = the science which deals with what falls
upon people…..
• Epidemiologist
• public health professionals who investigate patterns and causes of
disease and injury in humans
A case is a risk factor …
Infection in one person can be transmitted to others
(www)
Transmission
Cases
 Index – the first case identified
 Primary – the case that brings the infection into a population
 Secondary – infected by a primary case
 Tertiary – infected by a secondary case
T
S
Susceptible
Immune
Sub-clinical
Clinical
P
S
S
T
VIRUS SPREADING LAB
Please be quiet as we walk through the hallway to the
main staircase!
WHAT IS AN INDEX CASE?
Exit slip
Virus and bacteria
Friday
WHAT IS BACTERIA?
Do not write anything down until Ms.S tells
you!
What are bacteria?
• Single celled organisms
E. Coli O157:H7
can make you
very sick.
• Very small
• Need a microscope to see
• Can be found on most
materials and surfaces
Streptococcus
can cause strep
throat.
• Billions on and in your
body right now
USDA NIFSI Food Safety in the Classroom©
University of Tennessee, Knoxville 2006
This E. coli helps
you digest food.
Bacteria are ALIVE!
• What does it mean to be
alive?
• They reproduce (make more of
themselves)
• They need to eat
USDA NIFSI Food Safety in the Classroom©
University of Tennessee, Knoxville 2006
What do they look like?
• Some exist as single
Bacilli
cells, others
cluster together
Cocci
USDA NIFSI Food Safety in the Classroom©
University of Tennessee, Knoxville 2006
Cluster of cocci
Spiral
Bacteria contain:
•a singular, circular piece
of DNA
•tiny circular pieces of
DNA called plasmids
•ribosomes
Some bacteria have:
• flagella
•locomotion
• pili
•short, thicker
outgrowths that
help cell to
attach to
surfaces
How do bacteria reproduce?
• Grow in number not in size
• Humans grow in size from child to adult
• Make copies of themselves by dividing in half
• Human parents create a child
USDA NIFSI Food Safety in the Classroom©
University of Tennessee, Knoxville 2006
Bacteria
reproduce:
Asexually
(mitosis) using binary
fission.
Bacteria Characteristics
• aerobic-meaning that they require oxygen in order to
survive
• Sounds like “air”-> oxygen
• Other bacteria are anaerobes, meaning that they do not
require oxygen to survive.
• Most bacteria are harmless and offer beneficial functions
to living things and humanity.
• Where do you think some bacteria live that is beneficial to
humans?
Write this
down!
A Closer Look – Helpful Bacteria
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
sour cream
Lactobacillus bulgaricus –
used in the production of yogurt
How do bacteria eat?
• Some make their own food from
sunlight—like plants
Photosynthetic
bacteria
• Some are scavengers
• Share the environment around them
• Example: The bacteria in your stomach are
now eating what you ate for breakfast
• Some are warriors (pathogens)
Harmless bacteria
on the stomach
lining
• They attack other living things
• Example: The bacteria on your face can
attack skin causing infection and acne
USDA NIFSI Food Safety in the Classroom©
University of Tennessee, Knoxville 2006
E. Coli O157:H7
is a pathogen
DISCUSSION
• What type of growth do
bacteria exhibit?
• Exponential
• What are the two
kingdoms of bacteria?
• Archaebacteria – oldest
organisms on earth, live
in extreme conditions
• Eubacteria – “true”
bacteria
Archaebacteria
• Archaebacteria can
live in extremely
harsh environments
• They do not require
oxygen and can live
in extremely salty
environments as well
as extremely hot
environments
• Called the Ancient
bacteria
• Subdivided into 3
groups:
Methanogens
Thermoacidophiles
Extreme Halophiles
Write this
down!
71
Methanogens
• Live in anaerobic
environments (no
oxygen)
• Found in
swamps, sewage
treatment plants,
digestive tracts of
animals
Write this
down!
• Break down cellulose
in a cow’s stomach
• Produce marsh
(methane) gas
72
Extreme Halophiles
• Live in very salty water
• Use salt to generate ATP (energy)
• Dead Sea, Great Salt Lake
inhabitants
Thermoacidophiles or
Thermophiles
• Live in extremely hot
environments
• Found in volcanic vents, hot
springs, cracks on ocean floor
that leak acid
HOW DO BACTERIA
AFFECT US?
What is a pathogen?
Write this
down!
• Bacteria that make you sick
• Why do they make you sick?
• To get food they need to survive and reproduce
• How do they make you sick?
• They produce poisons (toxins) that result in fever, headache, vomiting,
and diarrhea and destroy body tissue
USDA NIFSI Food Safety in the Classroom©
University of Tennessee, Knoxville 2006
Where do you get a
pathogen?
Indirect contact
• Contact with people who are sick
• Direct or indirect
• Food, Water, or other Surfaces that are
contaminated
Foods that
could be
contaminated
Direct contact
A Closer Look – Where do you
get a pathogen
Write this
down!
Direct
Contact
Indirect
Contact
Foods and water
may be
contaminated
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
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
sour cream
Lactobacillus bulgaricus –
used in the production of yogurt
What are some common pathogens?
• Pathogenic E. coli
E. coli
O157:H7
(like O157:H7)
• Found in ground beef, contaminated fruits
and vegetables
• Salmonella
• Found in raw meats, poultry, eggs,
sprouts, fruit and vegetables
Salmonella
• Listeria
• Found in deli foods, lunch meats, smoked
fish and vegetables
Listeria
Examples of Pathogens
Salmonella
Staphylococcus
aureus
E. coli O157:H7
What shape are
these bacteria?
Cocci, bacilli, or
spiral?
Campylobacter
jejuni
How can I avoid pathogens?
• Wash your hands often so you won’t transfer bacteria to
your mouth or food
• Warm water with soap for 20 seconds, rub hard between fingers
and nails
• Cook food thoroughly to kill any pathogens that may be in
your food
• Store food properly to limit pathogen growth
• Cold temperatures (40F)
USDA NIFSI Food Safety in the Classroom©
University of Tennessee, Knoxville 2006
What is the definition of Disease?
• Any change that disrupts the normal function of
one or more body systems.
• What are Noninfectious diseases?
• Noninfectious diseases: Diseases caused by
exposure to certain chemicals or traits that are
inherited.
• Name one!
• What are infectious diseases?
• Infectious diseases: Diseases caused by a pathogen
.
• What is a pathogen?
• any microbe that causes disease
How are Infectious Diseases 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.
Diseases Caused by Bacteria
• How are bacterial infections cured or treated?
Use antibiotics to cure bacterial infections
• What are antibiotics?
 a chemical that can kill bacteria without harming a person’s cell
• What is antibiotic resistance?
Bacteria can develop a resistance to antibiotic and will no longer kill
This is what happens when you do not take medicine completely
Review discussion
Bacteria
Viruses
 What are pathogens?
 What are viruses?
 What is an infectious
 How do they spread?
disease?
 What do bacteria have that
helps them move?
 What are the three shapes of
bacteria?
How many
characteristics of life
do viruses possess?
*Genetic
Material
Are viruses
living?
Structure
Reproduction
Genetic Material
Growth and
Developmen
t
Obtain and
Use Energy
Response
to
Environmen
t
Change over time
RNA or DNA core
(center), protein coat
(capsid)
Cell membrane,
cytoplasm, genetic
material, organelles
Copies itself only inside
host cell--REPLICATION
Asexual or Sexual
DNA or RNA
DNA and RNA
NO
YES—Multicellular Organisms
NO
YES
NO
YES
NO
YES
21_03 Lytic and lysogenic cycles
Slide number: 1
Bacterial cell wall
Bacterial chromosome
1. Attachment:
Capsid combines
with receptor.
2. Penetration:
Viral DNA
enters host.
5. Release:
New viruses
leave host cell.
capsid
nucleic acid
a. Lytic cycle
b. Lysogenic cycle
4. Maturation:
Assembly of viral
components.
3. Biosynthesis:
Viral components
are synthesized.
prophage
Integration:
Viral DNA passed on
when bacteria reproduce.
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
How are diseases caused by
viruses?
 Is there a cure for viral diseases?
 Can we use antibiotics?
 Why or why not?
Measles
Rabies
Hepatitis
H1N1: Swine Flu
West Nile Virus
H5N1: Avian Flu
Agar plates
 Send one lab partner to Ms. S to grab your plates
 THE SEAL MAY NOT BE OPENED. IT IS A BIOHAZARD
 Gather your data, analyze, and draw conclusions
How are viruses different from
bacteria?
Exit Slip