Evolution In Action

1
Evolution In Action

• Bacteria

2
What are bacteria?

• Germs
• Bugs (not insects!)
• Microscopic
• Single-celled
• Live in clumps or colonies
• Not all are bad!

3
Types of Bacteria

• Circles
• Coccus
• Rods
• Bacillus
• Squigglies
• Spirillum

4
Reproduce rapidly

• Generation time 20 minutes
• Binary fission
• Makes a copy of DNA
• Cell splits in 2
• Daughter cell should be genetically identical
  to parent cell.

5
Exponential Growth
6
Infection

• Immune system kicks in
• Tries to kill off bacteria
• Too many infection
• Way too many death

7
Treatment?

• Antibiotics
• Anti against
• Biotic bacteria
• NOT EFFECTIVE AGAINST VIRUSES!
• Ex Penicillin, amoxicillin, tetracycline,
  erythromycin, etc.
• 1st discovered (by accident) in 1930s
• Widely available for use in 1940s

8
A little history

• WWI more soldiers died from infections than the
  injuries themselves!
• WWII antibiotics available almost none died
  from infections. (more deaths due to injury
  though)
• Read p. 61 Need to Know

9
Superbugs

• Resistant strains of bacteria
• Will not die from antibiotics
• Result of natural selection ? evolution
• Nature environment
• Bacterias environment?
• Inside the body!

10
Preventing Superbugs

• Do not demand an antibiotic from your doctor!
• DO NOT take an antibiotic for a viral infection!
• Take ALL of the prescribed antibiotics DO NOT
  stop once you feel better!
• Ask what else you can do to relieve symptoms

11
Write an essay!

• Read the 3 possible endings to the opening
  Scenario (p. 59)
• Write an essay answering p. 59-60 Analysis 1
  2.
• Should write 1 paragraph about each of the
  possible endings to the story.
• Explain why that ending is possible at that time
  in history.
• Each word (or a form of the word) from the list
  on page 60 must be used at least once in the
  essay.
• Please underline or highlight each word as you
  use it!