1. Antibiotics
Too Much
of a Good
Thing?
Biology Lecture Launchers
from Benjamin Cummings and Discovery Channel School
Presentation prepared by Andrew Stull
© 2009 Pearson Education, Inc.

2. Antibiotics
Your doctor
prescribes an
antibiotic and
specifically cautions
you to take every pill.
Why?
© 2009 Pearson Education, Inc.

3. Antibiotics
© 2009 Pearson Education, Inc.

4. Antibiotics
Checkpoint
What is an antibiotic?
a. It is a toxin used by bacteria to kill molds.
b. It is a drug that can kill infectious bacteria.
c. It is a chemical produced by the body to
defend itself against viruses.
d. It's an area with
conditions that
don't support life.
e. None of the
above are correct.
© 2009 Pearson Education, Inc.

5. Antibiotics
Checkpoint
What is an antibiotic?
b. It is a drug that can kill infectious bacteria.
© 2009 Pearson Education, Inc.

6. Antibiotics
Checkpoint
Human white blood cells ________.
a. carry oxygen and carbon dioxide to the
lungs
b. store antibiotics for release at sites of
infection
c. serve as one of the body's natural lines of
defense against microbial invaders
d. gather and eliminate antibiotics from the
site of an infection
e. All of these are correct.
© 2009 Pearson Education, Inc.

7. Antibiotics
Checkpoint
Human white blood cells ________.
c. serve as one of the body's natural lines of
defense against microbial invaders
© 2009 Pearson Education, Inc.

8. Antibiotics
Checkpoint
About half of the antibiotics produced today
__________.
a. end up in animal feed
b. are used by field hospitals in war zones
c. are shipped to third-world countries
d. become useless due to developing
resistance by bacterial populations
e. are stored for later use
© 2009 Pearson Education, Inc.

9. Antibiotics
Checkpoint
About half of the antibiotics produced today
__________.
a. end up in animal feed
© 2009 Pearson Education, Inc.

10. Antibiotics
Checkpoint
How do bacteria populations become drug
resistant?
a. Antibiotics remove drug-susceptible
individuals but leave those that are drug-
resistant.
b. Natural selection drives bacterial
populations to change.
c. Some individuals are genetically resistant
to antibiotics.
d. All of these are correct.
© 2009 Pearson Education, Inc.

11. Antibiotics
Checkpoint
How do bacteria populations become drug
resistant?
d. All of these are correct.
© 2009 Pearson Education, Inc.

12. Antibiotics
Checkpoint
Which of these is not an effective strategy to
prevent antibiotic resistance?
a. Don't stockpile antibiotics.
b. Don't demand antibiotics from your
physician.
c. Use antibiotics only as long as symptoms
remain.
d. Use antibiotics as prescribed.
e. Don't share antibiotics with others.
© 2009 Pearson Education, Inc.

13. Antibiotics
Checkpoint
Which of these is not an effective strategy to
prevent antibiotic resistance?
c. Use antibiotics only as long as symptoms
remain.
© 2009 Pearson Education, Inc.

14. Antibiotics
Summary
• We didn't have antibiotics before the 1940s.
• Alexander Fleming helped to develop the first
antibiotic from a mold.
• Antibiotics work to kill infecting bacteria.
• Natural variations exist within bacterial
populations that make some bacteria resistant
to antibiotics.
• Abuse of antibiotics promotes the development
of antibiotic-resistant bacteria.
© 2009 Pearson Education, Inc.