WHY DOES EVOLUTION MATTER NOW?

The genetic change in a group of organisms over time 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 hi-light 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

One month later-infection is getting better after antibiotics                                                                                                                     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” 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 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!!