Microbiology (Bio 370)
Practice Lecture Examination 7
2/3/2014 Kimberly
Name ______________________
I. Define: (do not use examples as definitions)
1. endospore
2. Gram positive bacterium
3. sporangium
4. ‘cardinal symptom of infection’
5. Gram’s iodine
II. Multiple Choice - Choose the most appropriate answer!
1. This group is neither Gram positive or negative: a) Staphylococcus;
b) Mycobacterium; c) E. coli; d) Streptococcus; e) none of the above
2. Endospores can be resistance to all of these but: a) pressure cooking at 2 atmospheres;
b) 70% alcohol; c) 95% alcohol; d) BacDown; e) pasteurization
3. A bacterium producing a spore may be initiated by: a) pH changes in media; b) lack of food;
c) lack of oxygen; d) too much oxygen; e) all of the above
4. In what size range are most bacteria? a) 50 microns; b) 2.5 cm; c) 500 nanometers;
d) 10-8 meters; e) 1 um
5. What is the correct order for Gram staining?
a) safranin; iodine; crystal violet; 95% EtOH
b) iodine; crystal violet; 95% EtOH; safranin
c) crystal violet; 95% EtOH, iodine; safranin
d) crystal violet; 95% EtOH; safranin; iodine
e) none of the above
III. True or False - Correct the false
______ 1. Resolution goes down as magnification goes up.
______ 2. The acronym, LPS, stands for lipoproteinaceous spore.
______ 3. Gram negative bacteria are red at the conclusion of Gram staining.
______ 4. Old cultures tend to go Gram negative.
______5. Kimberly said in class that the spore stain results in this color of spore = _____________.
IV. Fill in the blanks.
1. The difference between an endotoxin and an enteroxin is _______________________________.
2. The term for an endospore becoming ‘activated’ is ____________________.
3. This group of bacteria is neither Gram + or negative = ________________________.
4. The most potent toxins in the world come from this group (Gram + or neg.) _______________.
5. Kimberly reports endospores may remain viable for _____________________ years.
V. Essay - Explain the Gram stain process and why it works to differentiate major groups of bacteria.