Biology Assignment

Name___________________________

Microbes and Society – Ch. 11

15 pts.

Controlling Microbes outside the body

Part 1 - Physical methods (5 pts):

For each of the methods below, describe how they work to control microbes:

High temperatures:

Radiation:

Dessication (drying):

Filtration:

Low temperatures:

Part 2: For each scenario, use the list of physical methods in part 1 and decide which means of physical control is most appropriate. Provide the name of the method and briefly explain why you chose that method. (4 pts):

1. Sterilizing medical instruments between patients.

Method:

Why?

2. Preserving fresh foods like chicken and beef

Method:

Why?

3. Making water from a stream safe to drink

Method:

Why?

4. Sterilizing heat sensitive plastic medical devices

Method:

Why?

Part 3: Chemical Methods (6 pts):

Antiseptics/Disinfectants

Investigating an antimicrobial product

Look around your home and find either an antiseptic or a disinfectant. Make sure that the product claims to be antimicrobial!

Provide the following information concerning this product:

1. Name of the product: _______________________________

Ex. Lysol disinfectant spray

2. Active ingredient in this product: ___________________________________

*this is typically listed in small print on the front of the container but may be found on the back

Ex.

3. What types of microorganisms should this product be effective against?

4. Does this product make any claims of effectiveness?

(For example, kills 99.99% of germs)

5. Does this product list different instructions for sanitization vs. disinfection? If so, what are the differences?

6. Why do you think chemicals never claim to be 100% effective?