Chapter 2 Notes: Viruses and Bacteria
November 2010
Section 1 - Viruses - Pages 48 – 55
What is a Virus?
1. Define the following terms:
virus
_____________________________________________________________________
_____________________________________________________________________
parasite
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_____________________________________________________________________
host
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_____________________________________________________________________
2. Viruses are considered to be nonliving because:
a. ______________________________________
b. ______________________________________
c. ______________________________________
d. ______________________________________
3. How are viruses similar to living organisms? _________________________________
4. Besides humans what are some other organisms that viruses can infect?
_____________________________________________________________________
_____________________________________________________________________
5. When you are sick with a cold, are you the host or the parasite? __________________
Naming a Virus
6. How are viruses named?
a. _____________________
b. _____________________
c. _____________________
d. _____________________
Example of virus for each
_________________________
_________________________
_________________________
_________________________
Chapter 2 Notes: Viruses and Bacteria
November 2010
Section 1 - Viruses - Pages 48 – 55 (continued)
Shapes and Sizes of Viruses
7. Define Bacteriophage:
_____________________________________________________________________
_____________________________________________________________________
8. List four different shapes of viruses:
a. _______________________________
b. _______________________________
c. _______________________________
d. _______________________________
9. Viruses are ________________than cells and are measured in _________________.
Structure of Viruses
10. Label the two basic parts of the virus:
11. The function of A:
_____________________________________________________________________
_____________________________________________________________________
12. The function of B:
_____________________________________________________________________
_____________________________________________________________________
13. Why does a virus only invade a specific type of cell?
_____________________________________________________________________
_____________________________________________________________________
Chapter 2 Notes: Viruses and Bacteria
November 2010
Section 1 - Viruses - Pages 48 – 55 (continued)
How Viruses Multiply
14. How do viruses multiply?
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
15. Two types of viruses:
a.____________________ infects a cell immediately
b. ____________________ becomes part of the cell's genetic material and remains
silent for a while. These types of viruses can become suddenly active.
16. Give and example of a hidden virus ______________________.
Viruses and the Living World
17. Most viruses are harmful but some are useful. Give an example of each:
Harmful: ______________________________________________________________
Helpful:_______________________________________________________________
Thinking Critically:
18. Scientist Hypothesize that viruses could not have existed on Earth before living
organisms, such as bacteria, appeared. Use what you have learned about viruses to
support this hypothesis.
Chapter 2 Notes: Viruses and Bacteria
November 2010
Section 2 - Bacteria - Pages 56 – 65
The Bacterial Cell
1. Bacterial cells were first discovered in the late 1600's by Anton van Leewenhoek. How
did he discover them?___________________________________________________
_____________________________________________________________________
2. Bacterial cells are considered ____________________ because they lack a nucleus.
3. Where is the genetic material located in a bacterial cell? ________________________
4. What are the three basic shapes of a bacterial cell?
a. __________________________
b. __________________________
c. __________________________
5. Describe these basic structures of the bacterial cell then label on the diagram below:
a. cell wall ____________________________________________________________
b. cell membrane _______________________________________________________
c. cytoplasm _________________________________________________________
d. ribosomes___________________________________________________________
e. genetic material ______________________________________________________
f. flagellum____________________________________________________________
Chapter 2 Notes: Viruses and Bacteria
November 2010
Section 2 - Bacteria - Pages 56 – 65 (continued)
Two Kingdoms of Bacteria
6. List three characteristics of Archaebacteria:
a. ___________________________________________
b. ___________________________________________
c. ___________________________________________
7. List three characteristics of Eubacteria:
a. ___________________________________________
b. ___________________________________________
c. ___________________________________________
8. Why are Eubacteria and Archaebacteria placed in separate kingdoms?
_____________________________________________________________________
Reproduction in Bacteria
Define the following terms:
9. asexual reproduction
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_____________________________________________________________________
10. binary fission
_____________________________________________________________________
_____________________________________________________________________
11. sexual reproduction:
_____________________________________________________________________
_____________________________________________________________________
12. conjugation:
_____________________________________________________________________
_____________________________________________________________________
13. Bacterial reproduction can result in two different types of offspring:
a. _____________________ produces offspring genetically identical to the parents.
b. _____________________ produces offspring genetically different than the parents.
Chapter 2 Notes: Viruses and Bacteria
November 2010
Section 2 - Bacteria - Pages 56 – 65 (continued)
Survival Needs
14. Bacterial cells can obtain food from a variety of sources.
a. _________________ bacteria that make their own food.
b. __________________bacteria that obtain food by consuming other autotrophs or
heterotrophs.
15. The process of breaking down food to obtain energy is called ___________________.
16. endospore:
_____________________________________________________________________
_____________________________________________________________________
17. Why do bacterial cells form endospores?
_____________________________________________________________________
_____________________________________________________________________
Bacteria and the Living World:
18. List five positive roles of bacteria in today's society:
a. _____________________________________________
b. _____________________________________________
c. _____________________________________________
d. _____________________________________________
e. _____________________________________________
Thinking Critically:
19. Why do you think different types of bacteria are shaped differently?