Microbiology test focuses on “World of Bacteria II – Endospore – Forming Gram – Positive Bacteria”.
1. Which of the following are mesophilic saprophytes?
A. B.polymyxa
B. B.anthracis
C. B.subtilis
D. B.thuringiensis
Answer: C
Clarification: Bacillus subtilis are mesophilic saprophytes and are widely distributed in nature. This means they can grow best within a temperature range of approximately 25 to 40 degrees Celsius.
2. Which of the following causes “milky disease” of Japanese beetle grubs?
A. B.thuringiensis
B. B.popilliae
C. B.sphaericus
D. B.anthracis
Answer: B
Clarification: B.popilliae is a pathogenic species of Bacillus species that causes “milky disease” of Japanese beetle grubs.
3. Which of the following species is associated with spoilage of canned goods?
A. B.stearothermophiles
B. B.cereus
C. B.subtilis
D. B.sphaericus
Answer: A
Clarification: B.stearothermophilus is a thermophilic species having a maximum of 65 to 75 degrees Celsius. The endospores are highly resistant to heat and, therefore, this species is one of those associated with spoilage of canned goods.
4. Which of the following genus of species play an active role in the decomposition of urea?
A. Bacillus
B. Sporosarcina
C. Clostridium
D. Desulfotomaculum
Answer: B
Clarification: Sporosarcinae are widely distributed in fertile soil, where they play an active role in the decomposition of urea.
5. C.perfringens is the major causative agent of __________________
A. botulism
B. tetanus
C. gas gangrene
D. anthrax
Answer: C
Clarification: Clostridium perfringens is the major causative agent of the wound infection known as gas gangrene.
6. Which of the following Clostridium species has the ability to fix Nitrogen?
A. C.difficile
B. C.pasteurianum
C. C.tetani
D. C.thermosaccharolyticum
Answer: B
Clarification: C.pasteurianum is a mesophilic soil clostridium that is particularly noted for its ability to fix Nitrogen.
7. The genus Desulfotomaculum obtain energy by anaerobic respiration.
A. True
B. False
Answer: A
Clarification: The members of the genus Desulfotomaculum obtain energy by anaerobic respiration, with sulphate serving as the terminal electron acceptor and organic substrates such as lactic or pyruvic acid serving as the electron donors.
8. Pseudomembranous colitis is a disease of _________________
A. stomach
B. wounds
C. bowel
D. limbs
Answer: C
Clarification: C.difficile causes pseudomembranous colitis, a severe disease of the bowel.
9. Bacillus species cannot fix Nitrogen.
A. True
B. False
Answer: B
Clarification: Bacillus polymyxa has the ability to fix Nitrogen under anaerobic conditions.
To practice all areas of Microbiology for tests, .