You will have the opportunity to explore the effectiveness of six different antibacterial substances against a certain species of bacteria. You will follow scientific procedures by questioning, forming a hypothesis, setting up and conducting an experiment, analyzing results, and forming a conclusion. You will determine the comparative effectiveness of six antibiotics. What is the dependent variable? What is the independent variable?

The figure below shows the number of bacteria/ml in a series of patient's samples collected and cultured over time, and the resistance of these bacteria to a given antibiotic. This shows all of the following EXCEPT: Bacteria (number/ml) 108 107 106 105 104 103 0 Initiation of antibiotic therapy Bacteria count 1 2 3 5 6 Days Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings. Antibiotic resistance of bacterial population measured by amount of antibiotic needed to control growth 4 7 8 9 10 11 50 40 30 6 Antibiotic resistance (mg/ml) After an initial decline, the number of bacteria eventually rises again as antibiotic- resistant bacteria emerge and multiply At the beginning of antibiotic therapy, most of the bacteria were already resistant to 50 mg/ml of the antibiotic After about 5 days of treatment, the bacteria in the patient's samples were resistant to 50 mg/ml of the antibiotic None of the other four answers (All of these statements are true)

Bacterial species that are harmful, as well as others that are beneficial, are found living in the human body. To slow the rate of developing antibiotic resistance in bacteria, physicians are being encouraged to use "narrow-spectrum" antibiotics- those that target only a few bacterial types. How can the information learned by antibiotic sensitivity testing be used by physicians who must choose antibiotics that inhibit the growth of bacteria causing disease but that do not interfere with beneficial bacteria?

What is antibiotic resistance and how does it occur? What are multiple drug resistant pathogens?

Describe the purposes of positive and negative controls; identify in an experiment like a test for HIV, which portions are positive and negative controls and which is (are) the test.

In a series of infection experiments, a researcher discovers that the ID50 value for the infectious bacterium Parasiticum mucoides is 100, and that the ID50 for another infectious bacterium, Donoteatum thisbacterium, is 15,000.  Given these data, a person exposed to 1,000 bacteria of each type would be more likely to be infected by which bacterium? Group of answer choices There is no way to know given the information provided Both infections are equally likely Parasiticum mucoides Donoteatum thisbacterium

The bacterium Agrobacterium infects plants and causes plant cells to develop tumorlike cellular structures and begin synthesizing sets of proteins that protect the bacterium from the plant immune response, as well as synthesize nutrients that can be used exclusively by the bacterium. Researchers testing the efficacy of two new antibiotic treatments against Agrobacterium are tasked with designing an experiment to test their effectiveness. Which of the following describes the most appropriate control group in this experiment? A B с D a group of infected and untreated plants of the same species a group of uninfected and untreated plants of a different species a group of infected and untreated plants of a different species a group of uninfected and untreated plants of the same species

Why do you think there could be antibiotic resistant organisms before 1942 since bacteria need to "see" the antibiotic before it can become resistant?

Some antibiotics are effective against only a limited range of organisms. What is a term you learned in the virtual lab that is used to describe this phenomenon and describe what it means.

In a series of infection experiments, a researcher discovers that the ID50 value for the infectious bacterium Parasiticum mucoides is 2,000, and that the ID50 for another infectious bacterium, Donoteatum thisbacterium, is 150.  Given these data, a person exposed to 1,000 bacteria of each type would be more likely to be infected by which bacterium? There is no way to know given the information provided Both infections are equally likely Donoteatum thisbacterium Parasiticum mucoides