IBIO 203 California State University East Bay Biology Worksheet
Homework 8
All answers must be in your own words. Answers copied directly from the textbook, PowerPoint, or an online source will not be given credit.
Each question is worth 2 points.
1. You have read about many drugs used to treat bacterial infections. Explain why it is easier to develop a drug to treat bacterial infections compared to developing a drug to treat infection caused by other living microbes (fungi, protozoa, and helminthes.) Consider the types of cells causing the infection in your answer.
2. While there are drugs available to treat viral infections, again, it is a very small number compared to the number available to treat bacterial infections. Explain why it is easier to develop a drug to treat bacterial infections compared to developing a drug to treat viral infections. Consider the life cycle of a virus in your answer.
3. In 2015, the WHO surveyed 10,000 people about drug resistance. Seventy-five percent of them said that antibiotic resistance is due to the human body becoming resistant to the drug. Explain how you would correct this misconception?
4. Name and briefly describe the modes of action of the five major antimicrobial drug groups.
5. Imagine that you have set up a Kirby Bauer experiment on Mueller Hinton agar (non-selective agar) in order to test if Escherichia coli is susceptible or resistant to Drug X. After 24 hours, you notice a zone of inhibition (clear zone) around your antibiotic disc and determine that E. coli is susceptible to Drug X. You then take a cotton swab and subculture a sample from this zone of inhibition (where no growth was apparent) onto a new agar plate without antibiotics and after 24 hours you see growth of E.coli. What can you conclude about Drug X? Explain your answer for full credit.
6. Many visits to your physician do not result in a culture or a drug-test of the causative infectious agent, yet you still leave with a prescription for antibiotics. Name one instance where it would be best to be prescribed a narrow spectrum antibiotic. Name a second instance where it would be best to be prescribed a broad spectrum antibiotic. Justify your answers for full credit.
