Was our pond healthy? How do you know?

Agenda for Thursday Sept 29th 1. Quiz2. Cholera stuff

Learning Targets3. Understand the need for evidence4. Use mapping skills to plot data5. Use plotted data to infer a possible cause for the

disease

London 170 years ago

• A new and terrible disease was killing hundreds of people

• Several outbreaks

• Ideas about how it spread but no one attempted to prove the cause

Cholera• Problem in India and the far east since 400 B.C.

• Quickly spread because of travel and trade– Cause of over 21,000 deaths

• 19th century cholera caused widespread death in the U.S.– Poor sanitation & lack of understanding– Come and go– Not everyone got it

• Still a problem today in India and other places

What was a main reason cholera spread?

Agenda for Friday Sept 30th 1. Finish Cholera 2. Movie

Learning Targets3. Understand the need for evidence4. Use plotted data to infer a possible cause for

the disease

Vocab

• Hypothesis – educated guess based on observations

• Theory – based on extensive evidence and research

• Infer (inference) – reach conclusion based on the evidence you have

What is a theory?

Agenda for Monday Oct 3rd 1. Finish letter2. How to get rid of contaminants in water

How is chlorine both good and bad?

Agenda for Tuesday Oct 4th 1. Chlorine lab

If chlorine can be dangerous, how can we use it to kill organisms in our water?Agenda for Tuesday Oct 4th 1. Chlorination Lab

What are some hazards with using chlorine?

Agenda for Wednesday Oct 5th 1. Finish Chlorine stuff2. pH

Common Values of Chlorine

• Pool water has between 1 and 3 ppm chlorine

• Tap water has between .2 and .5 ppm

• Minimum level of chlorine must be .2 ppm to kill organisms