Download evolution - Appoquinimink High School

WHY DOES EVOLUTION
MATTER NOW?
EVOLUTION
The genetic change in a group of
organisms over time
Species change due to….
Natural Selection
 Variation
 Overproduction
 Struggle to Survive
 Differential Survival and Reproduction

This usually takes millions of
years…
Because multi-cellular organisms are so
genetically complex. (lots of DNA)
 For example….the horse….

But, in uni-cellular organisms
with few genes….
Evolution moves at a much faster pace!
Natural Selection can work in a matter of years!
Read the Engagement Activity and hilight useful information in diagnosisng
Susan.
In your group, determine what is
wrong with Susan. Make sure the
diagnosis fits the symptoms.
Bacteria have been causing
disease for millions of years.
Cholera bacteria
Legionella bactera
Today we can grow and culture
bacteria to identify it…
Colonies of bacteria
Antibiotics are used to kill
harmful bacteria
Antibiotic disk
Are of
No growth
But some bacteria we thought we had
“wiped out” are making a deadly
comeback!
Tuberculosis
bacterium
Debi’s Story
1. What were the main symptoms of Debi’s disease?
2. Why was Debi’s mom relieved after the diagnosis?
3.How did Debi get the disease?
4. How many medications did Debi take at first?
5. Why did she think she was ok?
6. What happened during her senior year?
7. Why did the pilot taking Debi to the hospital cancel?
8. Why did they surgically remove part of her lung?
Tuberculosis (TB)…

Is a disease of the respiratory system
TB infected lung section
TB free lung
TB infected lung
Chest x-ray showing TB
One month later-infection is
getting better after antibiotics
The “old cure”- Locked in a Sanitorium!
You either got better or you died there
Today?- A Multi-drug “cocktail”
of Antibiotics for 9 months!
The Evolution of Bacteria

Antibiotic resistance
You Are a Bacteria!!!
Yes, you are a population of
bacteria with variation in your
resistance to various antibiotic
drugs.
 Here is what can kill you.

DRUGS!!! (antibiotics)
against

life
Each colored bacteria can be killed
by a different antibiotic
You are an E. coli bacteria that
can be killed using antibiotics
that prevent the formation of the
cell wall. (penicillin)
BYE BYE!!!
You are an E. coli bacteria that can
be killed using antibiotics that
disrupt protein synthesis.
(tetracycline)
BYE BYE!!!
You are an E. coli bacteria that
can be killed using antibiotics
that blocks DNA synthesis.
(cipro)
BYE BYE!!!
This variant of E. coli bacteria is resistant
to all of the commonly used antibiotics.
IT LIVES AND
REPRODUCES!!!!
Once Every 20 minutes!!!!!!!
v
How Long before 1 tiny little
bacteria becomes 1million?
Why so many drugs for so long?
TB has developed a resistance to not just one,
But many kinds of antibiotics!
Some bacteria have gene that inactivates the antibiotics
And allows the bacteria cell to survive!
Antibiotic Resistant Strains of
Bacteria- Variation!
You go to the doctor, sick with the “flu”. The doctor says
you have a viral infection yet he gives you an antibiotic
anyway b/c you demand something to make you feel better!
(even though the antibiotic doesn’t kill a virus)


Did the doctor make
the correct decision in
prescribing the
antibiotic?
Explain


You only take the
antibiotic for 3 of the
14 days prescribed b/c
you “feel better”!
How are your actions
contributing to the
growth of an antibiotic
resistant strain of
bacteria?
You have just been infected with a serious bacteria. You are very
sick and need to figure out what is happening to your body so you
can get it treated.
-You need to discover the life cycle of your bacteria. This will tell
you how quickly the bacteria is spreading and how you contracted
your disease.
-How did you contract it? How is it spread?
-Is there a specific age group that this bacteria is found in? What are
the symptoms?
-what type of antibiotic is used to treat your disease and what the
antibiotic does to the bacteria cells as it works.
-What damage does your bacteria do to the body? What are the
symptoms?
Prepare a Poster (one powerpoint slide) about your bacteria so we
make sure that this does not become an epidemic in our classroom!!