Chapter 19 Review Questions
Section 19-1: Bacteria:
1. What are prokaryotes? _____________________________________________________
2. True or False: Prokaryotes are much smaller than most eukaryotic cells. _____________
3. What are the 2 different groups of prokaryotes? _______________ and _______________
4. Which is the larger of the two kingdoms of prokaryotes? _________________
5. Where do eubacteria live? ____________________________________________________
6. What protects a prokaryotic cell from injury? ____________________________________
7. What is peptidoglycan? ______________________________________________________
8. What are methanogens, and where do they live? _________________________________
_____________________________________
9. Label the following diagram of a typical prokaryote:
10. What are 4 characteristics used to identify prokaryotes?
a. ___________________________________________
b. ___________________________________________
c. ___________________________________________
d. ___________________________________________
11. What are each of the differently shaped prokaryotes called:
a. Rod-shaped are called __________________
b. Spherical-shaped are called ______________
c. Corkscrew-shaped are called _____________
12. A method of telling two different types of eubacteria apart by using dyes is called
________________________
13. What colors are Gram-positive and Gram-negative bacteria under the microscope when
treated with Gram stain? __________________________________________
14. What are flagella? ___________________________________________________________
15. True or False: Some prokaryotes do not move at all. ___________
16. Complete the table about prokaryotes classified by the way they obtain energy:
Group
Description
Organism that carries out photosynthesis in a manner similar to that of
plants.
Chemoautotroph
Organism that takes in organic molecules and then breaks them down
Photoheterotroph
17. Complete the table about prokaryotes classified by the way they release energy:
Group
Description
Organisms that require a constant supply of oxygen
Obligate anaerobes
Facultative anaerobes
18. Facultative anaerobes can switch between cellular respiration and __________________
19. What occurs in the process of binary fission? ____________________________________
20. What occurs during conjugation? ______________________________________________
21. True or False: Most prokaryotes reproduce by conjugation. __________
22. What is an endospore? _______________________________________________________
23. What would happen to plants and animals if decomposers did not recycle nutrients?
___________________________________________________________________________
24. How does nitrogen fixation help plants? ________________________________________
__________________________________
25. What kind of relationship do many plants have with nitrogen-fixing bacteria? _________
___________________________________________________________________________
26. How can bacteria be used to clean up an oil spill? ________________________________
____________________________________
Section 19-2: Viruses:
1. What are viruses? _________________________________________________________
2. What do all viruses have in common? __________________________________________
3. True or False: Most viruses are so small that they can be seen only with the aid of a
powerful electron microscope. ______________
4. What is the structure of a typical virus? _________________________________________
5. A virus’s protein coat is called a (an) ________________.
6. How does a typical virus get inside a cell? _______________________________________
____________________________________
7. Why are most viruses highly specific to the cells they infect? ______________________
______________________________________________
8. What are bacteriophages? ____________________________________________________
9. Circle the letter of each sentence that is true about a lysogenic infection:
a. The virus lyses the host cell immediately.
b. The virus embeds its DNA into the host cell’s DNA.
c. The virus’s DNA is replicated along with the host cell’s DNA.
d. A host cell makes copies of the virus indefinitely.
10. What is a prophage? _________________________________________________________
11. What are retroviruses? _____________________________________________________
12. Circle the letter of each reason why some biologists do not consider viruses to be alive:
a. They can’t infect living cells.
b. They can’t evolve.
c. They can’t regulate gene expression.
d. They can’t reproduce independently.
13. What are pathogens? ________________________________________________________
14. What are antibiotics? ________________________________________________________
15. What are some examples of bacterial diseases in animals? ________________________
16. What is sterilization? _________________________________________________________
17. A chemical solution that kills pathogenic bacteria is called a (an) ___________________
18. What are some human diseases that viruses cause? ______________________________
19. What are some examples of a viral disease in animals? ____________________________
20. Cancer-causing viruses are known as __________________________________________
21. What are viroids? ___________________________________________________________