Drugs In Medicine

9.Which of the following statements about antibiotics is not correct?

10.In a laboratory experiment, paper discs soaked in different antibiotics are placed on a bacterial lawn. A clear zone around a disc indicates that the bacteria are

11.Which of the following is a reason why antibiotics generally do not harm human cells?

12.A scientist discovers a new molecule that stops bacteria from reproducing but does not kill them. Why might this still be useful as an antibiotic?

13.A scientist tests two bacterial strains (X and Y) with antibiotics using the disk diffusion method. On the agar plate with strain X, there is a clear zone around the penicillin disk but no zone around the methicillin disk. On the plate with strain Y, there is no clear zone around either disk. What can be concluded?

14.The results of an antibiotic sensitivity test using paper discs on a bacterial lawn are as follows. Disc 1 (control) shows no clear zone. Disc 2 (antibiotic P) shows a clear zone of 15 mm. Disc 3 (antibiotic Q) shows a clear zone of 8 mm. Disc 4 (antibiotic R) shows no clear zone. Which antibiotic is most effective against this bacterium?

15.Which of the following is a method by which bacteria can become resistant to antibiotics?

16.A new antibiotic is discovered that prevents bacterial ribosomes from functioning. Why is this antibiotic unlikely to harm human cells?

17.In a hospital, 100 patients with a bacterial infection are treated with antibiotic X. After treatment, 95 recover, but 5 do not and their bacteria are found to be resistant to X. Which statement best explains this?

18.Which of the following is a way to reduce the development of antibiotic resistance?

19.The table shows the minimum inhibitory concentration (MIC) of an antibiotic for two bacterial strains. | Strain | MIC (μg/mL) | |---|---| | A | 2 | | B | 32 | Which strain is more resistant to the antibiotic?

20.A student places paper discs soaked in different concentrations of an antibiotic on a bacterial lawn. The diameters of the clear zones are: 0 μg/mL: 0 mm; 1 μg/mL: 5 mm; 10 μg/mL: 15 mm; 100 μg/mL: 20 mm. What conclusion can be drawn?

21.A new drug is discovered that inhibits an enzyme unique to bacteria. In clinical trials, it kills 99.9% of bacteria in a culture. However, after several days, the bacteria grow back. Which is the most likely explanation?

22.In a disk diffusion test, a paper disc soaked in antibiotic is placed on a bacterial lawn. After incubation, a clear zone of 15 mm is observed around the disc. What does this clear zone indicate?

23.A student sets up an experiment to test the effectiveness of three antibiotics (X, Y, Z) against a bacterial strain. Paper discs soaked in each antibiotic are placed on an agar plate spread with bacteria. After incubation, the diameters of the clear zones are: X = 12 mm, Y = 8 mm, Z = 18 mm. Which antibiotic is most effective against this strain?

24.A student places paper discs soaked in different concentrations of an antibiotic on a bacterial lawn. The diameters of the clear zones are: 0 μg/mL: 0 mm; 1 μg/mL: 5 mm; 10 μg/mL: 12 mm; 100 μg/mL: 18 mm. What conclusion can be drawn?

25.In a study, the levels of three antibiotics (A, B, C) were measured in stream water upstream and downstream of a dumpsite. The upstream levels were: A=10, B=8, C=3 arbitrary units. Downstream levels were: A=12, B=34, C=2. Which antibiotic shows the greatest percentage increase?

26.A student investigates the effect of an antibiotic on bacterial growth using the disk diffusion method. The student places paper discs soaked in different concentrations of the antibiotic on an agar plate spread with bacteria. After incubation, the diameters of the clear zones are measured. Which of the following graphs best represents the expected relationship between antibiotic concentration and zone diameter?

27.In an experiment, a bacterial culture is exposed to a sub-lethal concentration of an antibiotic for many generations. After 100 generations, the minimum inhibitory concentration (MIC) of the antibiotic for the culture increases from 2 μg/mL to 32 μg/mL. Which of the following best explains this observation?

28.A study measured the levels of three antibiotics (A, B, and C) in stream water upstream and downstream of a dumpsite. The results are shown in the table. | Antibiotic | Upstream level (arbitrary units) | Downstream level (arbitrary units) | |------------|---------------------------------|-----------------------------------| | A | 10 | 12 | | B | 8 | 34 | | C | 3 | 2 | Calculate the percentage increase in antibiotic B from upstream to downstream.

29.In a disk diffusion test, a paper disc soaked in antibiotic is placed on a bacterial lawn. After incubation, a clear zone of 15 mm is observed around the disc. The same antibiotic is tested on a different bacterial strain, and the clear zone is 5 mm. Which of the following conclusions is most valid?

30.A student places paper discs soaked in different concentrations of an antibiotic on a bacterial lawn. The diameters of the clear zones are: 0 μg/mL: 0 mm; 1 μg/mL: 5 mm; 10 μg/mL: 12 mm; 100 μg/mL: 15 mm. Which of the following is the most likely explanation for the small increase in zone diameter between 10 μg/mL and 100 μg/mL?

31.Which of the following is a medicinal drug used to treat the symptoms or causes of a disease?

32.Antibiotics are effective against viruses.

33.Match each term with its correct description.

34.Patients should stop taking antibiotics as soon as they feel better to avoid side effects.

35.Which of the following are reasons why antibiotics are becoming less effective? (Select all that apply)

36.Place the following events in the correct order to show how antibiotic resistance develops in a bacterial population.

37.A student investigates the effect of an antibiotic on bacterial growth using the disk diffusion method. The student places paper discs soaked in different concentrations of an antibiotic on a bacterial lawn. After incubation, the diameters of the clear zones are: 0 μg/mL: 0 mm; 2 μg/mL: 6 mm; 4 μg/mL: 10 mm; 8 μg/mL: 14 mm. What is the relationship between antibiotic concentration and the diameter of the clear zone?

38.A patient is prescribed a course of antibiotics consisting of 2 tablets per day for 7 days. How many tablets will the patient take in total?

39.Complete the sentence about drug metabolism.

40.State one way individuals can help prevent the incidence of antibiotic resistance increasing.

41.Explain why antibiotics are not effective against viruses.

42.A patient is prescribed a course of antibiotics consisting of 2 tablets per day for 7 days. How many tablets will the patient take in total?