Griffith- Microbe

Day 1
What is a Microbe?
ž  With
the person at your table, take 2
minutes to brainstorm some ideas of
What are microbes? .
ž  Come up with 1-2 ideas to share with
the group including examples of
microbes and if they are harmful/helpful.
Which one is the Microbe?
Elephant: REDUCED 5X
Bacteria: MAGNIFIED 10,000X,
many bacteria stacked on top of
each other
Which one is the Microbe?
Test tube with bacteria
Elephant: REDUCED 5X
Bacteria: MAGNIFIED 10,000x
Definition
ž  A
microbe is anything you have to
use a microscope to look at.
ž  Microscope objectives are used for
magnification (10x, 20x, 60x, etc)
Examples of Microbes
ž  Viruses
Norovirus
Influenza
Examples of Microbes
ž  Bacteria
MRSA
Bifidobacterium
Examples of Microbes
ž  Archaea-many
known as extremophiles
Acid mine drainage
Yellowstone thermal hot springs- 176° F water
temperatures!
Examples of Microbes
ž  Fungi
Mushrooms
Candida albicans
Examples of Microbes
ž  Protists-
known as the first eukaryotes!
Trypanosoma spp. cause sleeping
sickness
Plasmodium spp. cause malaria
Activity- Good, Bad, and Ugly
ž  In
your group, choose one of the
sections of the circle that you believe
represents the percentage of all
microbes that are harmful to humans.
ž  Present your pie chart to the class and
explain why you chose that percentage.
Most microbes do not cause us
harm and many contribute to
basic functions.
ž  Protect
us from pathogens
ž  Contribute to our nutrition
ž  Promote immune function
ž  Role in development
What about the small percentage
of harmful microbes?
ž  These
are known as pathogens
ž  Cause infections/disease
Treatment: Antibiotics
ž  Antibiotic
problem
resistance is becoming a big
Activity- Abundance
ž  Using
the pie charts and provided
sections, decide with your group how
much of the day you will encounter or be
around a microbe.
Microbes in Ecosystems
ž  Microbes
make up important parts of an
ecosystem
ž  What is an ecosystem? With a partner,
brainstorm and come up with examples
of ecosystems
Parts of an Ecosystem
ž  Biotic
and Abiotic factors
—  Biotic- living components such as animals,
plants, fungi, bacteria
—  Abiotic- non-living components such as
temperature, sunlight, water, nutrients
—  Example: Imagine an oak tree living in the
forest.
○  How can it be affected by different biotic and
abiotic factors?
○  How does the tree depend on these factors for
survival?
Symbiosis
ž  Nothing
lives in isolation
ž  Long term interactions between 2 (or
more) species
ž  Relationships between organisms can
be +/+, +/-, +/0
ž  Physical and Chemical Processes
—  Production of light
—  Digesting plant material
—  Making structures (i.e. coral reef)
Humans and Microbes
ž  Examples
—  Nose
—  Skin
—  Digestive System
ž  What
These are
examples of
ecosystems!
does this mean for human health?
ž  Prebiotics and Probiotics
Closing
ž  You
are a scientist investigating
microbial and human interactions.
Tomorrow, bring to class one question
about microbes, symbiosis, and humans
that you want to investigate further.
Day 2
Intro to Dr. Rio s Lab
Rio lab, March 2012
Research focused on symbiosis
ž  Microbe:Microbe & Host:Microbe interactions
ž  Use of model systems
ž  What drives the evolution of symbiosis
(molecular and ecological cues)?
ž  What is involved in maintaining the symbiosis
over time?
ž  How do we encourage good relations between
species over bad relations?
ž 
Leeches in Research
• Strict blood feeders
• Water-dwelling
• Hermaphrodite
• Deposit cocoons
• One of the best models in
Neurobiology
• A great model for studying
digestive tract ecosystems
Use in Medicine
ž 
Historically
—  Used to balance the body and remove apparent
excess blood if a person had a red or swollen area
—  Became used to treat almost every ailment whether
they were effective or not
—  Discredited by modern medicine; doctors preferred
antibiotics and contemporary techniques.
ž 
Today
—  FDA approved treatment
—  Especially useful in microsurgery to drain congested
blood or for reconstructive surgery to aid in
reattachment of body parts.