Worksheet: Bacteria
A)Web site name: Cells Alive
Web site address:
Look at the diagram of a bacterial cell and click on the labels to get details.
1). / What does the Nucleoid contain? ______2). / Are there more “ribosomes” or “flagellum” shown in the diagram? ______
Click on “Cell wall”
3). / What is the function of the capsule? ______
4). / What is the bacterial cell wall composed of ? ______
5). / What shape is a “coccus” bacterium? ______
6). / What is the function of pili? ______
Click on “Microbiology” at the top left of the screen, and then “Dividing Bacteria”
7). / How do bacteria reproduce? ____________
8). / Why is the earth not covered with bacteria?
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9). / What happens in the “lag” phase? ______
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Click on “Microbiology” at the top left of the screen, and then “Parasites”
10). / Why is Cryptosporidium increasingly important? ______
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11). / What diseases can Entamoeba cause? ______
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12). / There is a rapid influx of ______into a contacted cell.
13). Which animal carries Giardia? ______
14). What are the two “eyes” on Giardia? ______
B)Web site name: FCCJ
Web site address:
15). Can most bacteria cause disease? ______
16). Give an example of a bacterium that cannot live outside human cells:
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17)What is “colonisation resistance”? ______
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18). What problems can be caused by taking antibiotics? ______
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19). What vitamin is produced by bacteria in the gut? ______
20). Why is the stomach usually sterile? ______
21). What are three bacteria found in the small bowel (small intestine)?
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22). Where is E. coli usually found? ______
23). Who is often infected with Staph. aureus? ______
24). Where are spirochaetes found? ______
C)Web site name: University of Kansas
Web site address:
25). What does the “E.” in E. coli stand for ? ______
26). How much of the bacteria in an adult’s intestine is E. coli? ______%
27). When was Escherichia first isolated and characterized? ______
28). What parts of the body usually do not contain “helpful” bacteria?
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29). Which strain of E. coli causes hemorrhaging? ______
30). Which toxin does this strain produce? ______
31). What problems, apart from hemorrhaging, does this strain cause to people who are infected with it? ______
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D)Web site name: New Scientist magazine
Web URL: -ban-cuts-drug-resistant-bugs.html
Read “Antibiotic ban cuts drug resistant bugs”
32). What did the WHO report conclude in August 2003?
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33). Why are low doses of antibiotics used in animal feed? ______
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34). Which country is the world’s largest exporter of pork? ______
35). What change was seen in the percentage of Enterococcus that were antibiotic resistant?
Before the ban: ______% resistant, after the ban ______% resistant.
36). List any household items that now routinely contain antibiotics, or other anti-bacterial chemicals: ______
E)Web site name: Centers for Disease Control
Web URL:
37). What serious complications can Chlamydia cause? ______
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38). Roughly how many infections were there in 2006? ______
39). Why are teenage girls and young women at high risk? ______
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40). How much more likely are women infected with Chlamydia to get infected with HIV? ______
Commercial companies, such as Monsanto, also use bacteria to add genes to crop plants to produce a “transgenic” plant. This is often called “recombinant DNA”, because it re-combines DNA from different species.
F)Web site name: Monsanto Inc.
Web site address:
41). What enzymes were needed to help transfer genes between species?
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42). What was the first commercial application of recombinant DNA technology?
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43). Which bacterium is used by Monsanto for introducing genes into plants?
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44). Which crops are hard to grow from single cells? ______
45). Roughly what percentage of potato cells accept new genes? ______%
46). What is the difference between traditional plant breeding and plant biotechnology? ______
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47). What is Bacillus thuringiensis ? ______
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48). How does this bacteria kill pests? ______
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49). Why are chemical insecticides rarely used in Africa? ______
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Some people are concerned about the process of moving genes from one species to another ( recombinant DNA or genetic engineering ). The last website looks at some of the potential problems
G)Web site name: San Francisco State University
Web site address:
Click on one of the essays about Genetic engineering.
50). Which essay did you pick? ______
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51). Briefly summarize the essay: ______
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