Eubacteria and archaebacteria differ in

1. Eubacteria and archaebacteria differ in • the presence of a nucleus. • the makeup of their cell walls. • size. • the presence of a cell wall.

2. Unlike eubacteria, archaebacteria • have cell walls. • are prokaryotes. • have two cell membranes. • are thought to be the ancestors of eukaryotes.

3. Which of the following is NOT a way in which archaebacteria and eubacteria differ? • Archaebacteria lack an important carbohydrate found in the cell walls of eubacteria. • The two groups have very different membrane lipids. • Archaebacteria have gene sequences that are similar to those of eukaryotes. • Archaebacteria follow the lytic cycle, while eubacteria follow the lysogenic cycle.

4. Which of the following are members of the kingdom Archaebacteria? • methanogens • eubacteria • eukaryotes • E. coli

5. Figure 19–1

6. The structure in Figure 19–1 represents a(an) • virus. • archaebacterium. • methanogen. • eubacterium.

7. Which structure or structures shown in Figure 19–1 have key differences in eubacteria and archaebacteria? • A, B, C • A, B, E • D only • A only

8. Figure 19–2 shows how prokaryotes can be identified by • the composition of their cell walls. • their reaction to the Gram stain. • their cell shapes. • their methods for obtaining energy.

9. Which cell shape in Figure 19–2 is called a coccus? • A • B • C • none of the above

10. When treated with Gram stain, Gram-positive eubacteria appear • violet. • pink. • yellow. • orange.

11. Bacilli, cocci, and spirilla are • Gram stains. • shapes of prokaryotes. • methods of prokaryotic movement. • ways that prokaryotes obtain energy.

12. Which of the following is(are) used to identify prokaryotes? • cell shape • the way prokaryotes move • the way prokaryotes obtain energy • all of the above

13. Where are you likely to find a photoautotroph? • in your refrigerator • in the darkness of the ocean • in your digestive system • near the surfaces of lakes, streams, and oceans

14. Unlike photoautotrophs, chemoautotrophs obtain energy • directly from the sun. • directly from inorganic molecules. • indirectly from organic molecules. • indirectly from other organisms.

15. Most prokaryotes are • heterotrophs. • photoautotrophs. • chemoautotrophs. • photoheterotrophs.

16. A method called Gram staining is used to tell • what shape a prokaryote has. • how a prokaryote obtains energy. • what kind of cell wall a prokaryote has. • whether a prokaryote has flagella.

17. Which of the following describes a role of bacteria in the environment? • carrying out photosynthesis • recycling nutrients • fixing nitrogen • all of the above

18. Bacteria are sometimes called nature’s recyclers because they • undergo conjugation. • break down nutrients in dead matter. • can switch between respiration and fermentation. • carry out photosynthesis.

19. Bacteria that break down the nutrients in dead matter into simpler substances that are taken up by plant roots are called • endospores. • flagella. • photoautotrophs. • decomposers.

20. Nitrogen fixation involves each of the following EXCEPT • soybeans. • Rhizobium. • fertilizer. • nodules on roots.

21. Which of the following is produced when bacteria break down complex compounds in sewage? • carbon dioxide gas • purified water • nitrogen • all of the above

22. Humans use bacteria to • clean up small oil spills. • mine minerals from the ground. • synthesize drugs. • all of the above

23. Bacteria living in extreme environments may be a good source of • antibiotics. • heat-stable enzymes. • nitrogen-fixing bacteria. • Gram stains.

24. The outer protein coat of a virus is called a • DNA core. • capsid. • bacteriophage. • tail sheath.

25. All viruses are made of proteins and • nucleic acids. • prophages. • bacteriophages. • endospores.

26. A viral capsid functions to • bind the virus to the surface of a host cell. • transcribe viral genes. • force a host cell to make copies of the virus. • destroy a host cell.

27. The instructions for making new copies of a virus are • a part of a virus’s capsid. • coded in surface proteins attached to the protein coat. • coded in either RNA or DNA. • found only in bacteriophages.

28. What is the basic structure of a virus? • DNA or RNA surrounded by a protein coat • a capsid surrounded by a protein coat • a tail sheath surrounded by tail fibers • a tiny cell surrounded by a cell wall

29. Viruses • are all about the same size. • vary greatly in size and structure. • rarely contain DNA or RNA. • can be seen with a basic compound light microscope.

30. A lytic infection concludes with the • embedding of viral DNA into the host cell’s DNA. • production of a prophage. • bursting of the host cell. • production of messenger RNA.

31. A prophage is made of • bacteriophages. • carbohydrates. • capsid proteins. • viral DNA.

32. Bacteriophages infect • other viruses. • bacteria only. • any available host cell. • cells undergoing the lytic cycle.

33. Unlike lytic viruses, lysogenic viruses do NOT • inject their genetic material into the host cell. • enter the lytic cycle. • lyse the host cell right away. • infect host cells.

34. During a lytic infection, the host cell is • destroyed. • prepared for the lysogenic cycle. • copied many times over. • all of the above

35. Which of the following is a way that bacteria cause disease? • by capsids • by nitrogen fixation • by conjugation • by releasing toxins

36. Bacteria that cause disease are called • viruses. • pathogens. • endospores. • antibiotics.

37. A bacterial infection results when bacteria • break down the body’s tissues. • lyse following the lytic cycle. • live as obligate aerobes in the absence of oxygen. • undergo conjugation inside the body.

38. Which of the following diseases is NOT caused by a bacterium? • tooth decay • tuberculosis • AIDS • Lyme disease

39. Food stored in a refrigerator will keep longer because the bacteria that spoil food • die at low temperatures. • take longer to multiply at low temperatures. • require light to live. • grow more slowly in the dark.

40. Which of the following is a characteristic of bacteria that is key to keeping them under control? • Most bacteria cannot survive high temperatures for long periods. • Most bacteria are resistant to harmful chemicals. • Most bacteria form endospores when subjected to harsh conditions. • Most bacteria do not cause food to spoil.

41. Which of the following will NOT kill bacteria? • refrigeration • boiling • chemical disinfection • frying

42. Which of the following is a proper use of disinfectants? • as an antibiotic • to start conjugation • to sterilize a hospital • to preserve foods

43. Which of the following is NOT a viral disease? • botulism • AIDS • measles • polio

44. Viral diseases can be • treated with antibiotics and prevented with vaccines. • treated with vaccines and prevented with antibiotics. • prevented with antibiotics but not treated with vaccines. • prevented with vaccines but not treated with antibiotics.

45. Plant viruses have a difficult time entering the cells they infect partly because • plant viruses are weaker than animal viruses. • plant cells have tough cell walls. • many plant viruses are spread by insects. • plant viruses do not have a protein coat.

46. Viruses cause disease by • producing toxins that harm the body. • reproducing independently inside the body. • forming endospores in the body. • disrupting the body’s normal equilibrium.

47. Scientists reason that archaebacteria may be the ancestors of eukaryotes. If this is true, then archaebacteria and eukaryotes share a common ancestor that is more recent than the common ancestor of archaebacteria and eubacteria. _________________________ • True • False

48. Many archaebacteria live in extreme environments, such as in Utah’s Great Salt Lake. _________________________ • True • False

49. Figure 19–2 shows the three shapes of viruses. _________________________ • True • False

50. The spiral-shaped organism labeled B in Figure 19–2 is an example of a spirillum. _________________________ • True • False