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Evolution of Antibiotic or Pesticide Resistance

For many years, antibiotics have been effectively used to treat bacterial disease; and pesticides have been used to protect our agricultural crops from many kinds of pests, including insects, worms (nematodes), fungi, or agricultural weeds, for example.

A growing concern for treating bacterial diseases or pest outbreaks is the evolution of antibiotic or pesticide resistance by bacterial or pest populations. Resistance means that a particular antibiotic is no longer effective in treating a disease, or that a particular pesticide will no longer prevent crop damage. This resistance can be viewed as evolution of a new trait at the population level, which is resistance to an antibiotic or to a pesticide. you will explore specific examples of antibiotic or pesticide resistance.

Answer the following.

1.Select and describe one example of antibiotic resistance or pesticide resistance. Be specific in your choice.
Describe the background for your choice of resistance. Include details about the disease or pest and the established control strategies. How have we used antibiotics (to treat a particular disease), or pesticides (to protect from a pest); and how has this changed?
2.Explain how the resistant trait evolved based on principles of natural selection and evolution of a trait at the population level.
3.For your specific example, what are the consequences of resistance in terms of human health or crop loss / damage?
4.What steps can be taken to prevent or slow down the evolution of antibiotic or pesticide resistance? Do you think we will succeed in doing so? Why or why not?

Solution Preview

Staphylococcus aureus is a common bacteria, normally found on the skin. If it gains entry into the body, it can lead to issues such as pneumonia, abscesses, bone infections and even infections of the heart valve. Prior to the 1940s, almost all Staphylococcus aureus were vulnerable to penicillin. Today, 90% of Staphylococcus aureus are resistant to Penicillin, making it ineffective as a treatment.

Penicillin works by preventing the formation of peptidoglycan cross links in the cell wall. Staphylococcus constantly builds and breaks down its cell wall. Penicillin binds the enzyme that links the peptidoglycan cross links, rendering it non functional. However, the enzyme that breaks down these links continues to function. (http://www.drugs.com/penicillin.html)

Resistant Staphylococcus work by using an enzyme called Penicillinase which cleaves a ring of the penicillin molecule, rendering it ineffective. Antibiotic resistance in Staphylococcus arose as result of natural selection. ...

Solution Summary

This solution analyzes antibiotic resistance using an example and it's consequences as well as providing general theory on how this resistance effect is a result of natural selection. References are also provided to further validate the findings. 599 words.

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