This set of Marine Biotechnology Multiple Choice Questions & Answers (MCQs) focuses on “Aquaculture Medicine”.
1. Disease caused by Aeromonas spp. is cause of mortality in aquaculture.
a) True
b) False
View Answer
Explanation: Diseases caused by various pathogens are major causes of mass mortality of culture organisms in aquatic food production systems. Major pathogens include Vibrio spp. and Aeromonas spp.
2. ________________ is a live microbial feed supplement.
a) Probiotic
b) Prebiotic
c) Flocculent
d) Humic acid
View Answer
Explanation: Most widely quoted definition for probiotics by Fuller (1989) is “a live microbial feed supplement which beneficially affects the host animal by improving its intestinal balance”.
3. _______________ are known to be present in intestine of healthy fish.
a) Lactic acid bacteria
b) Methanogens
c) Salmonella
d) Shigella
View Answer
Explanation: Lactic acid bacteria (LAB) such as lactobacillus and bifidobacteria are residents of human gastrointestinal tract where their function is to convert lactose to lactic acid and reduce pH of the intestinal environment. LAB have been reported in intestine of healthy fish.
4. Which is not a characteristic of Bacillus spp.?
a) Bacteriocin production
b) Immunostimulation
c) Spore-forming
d) Reproduction by budding
View Answer
Explanation: Bacillus spp. are commonly studied probiotics that are spore forming and yeasts species. Other characteristics include production of antimicrobial peptides (bacteriocins) and immunostimulation.
5. Phytoplankton produce substances toxic to other bacteria.
a) True
b) False
View Answer
Explanation: Phytoplankton (microalgae species such as Skeletonema costatum) produce bacterial inhibitory toxins such as bactericidal organic compounds. Many microalgae have been reported to produce antibiotics.
6. _________________ is a notable mechanism of virulence.
a) Surface attachment
b) Sulfide production
c) Biofilm formation
d) Siderophore production
View Answer
Explanation: Iron is essential for microbial growth which is otherwise limited in fish tissues and body fluids and in insoluble ferric Fe3+ form. Siderophores are iron-binding agents and siderophore production, a mechanism of virulence in many pathogens.
7. Surface attachment is important for all probiotics.
a) True
b) False
View Answer
Explanation: Surface attachment is usually required for most bacterial probiotics to spring into action. This characteristic has been reported in enhanced potency of biofilm forming bacteria compared to the non-attaching ones.
8. The double layer method and disc diffusion method are used for ________________
a) endophytic fungi
b) endophytic bacteria
c) screening inhibitory compounds
d) screening anticancer compounds
View Answer
Explanation: Inhibitory compounds produced by various microbes can be screened in vitro using four methods namely double layer method, disc diffusion method, well diffusion method, and the cross-streak method.
9. BioPlus2B is a ________________
a) probiotic
b) fertilizer
c) pond buffer
d) carbon source
View Answer
Explanation: BioPlus2B is a commercial probiotic used in aquaculture. An efficient alternative to probiotics the product is a mixture of Bacillus subtilis and Bacillus licheniformis that enhance the pathogen resistance in aquaculture animals.
10. Super PS – an aquaculture probiotic contains ___________________
a) pathogenic bacteria
b) spore producing fungi
c) photosynthetic bacteria
d) cyanobacteria
View Answer
Explanation: Super PS is a soil probiotic comprising photosynthetic sulfur bacteria that utilizes hydrogen sulfide as an electron donor and converts it into sulfates (less harmful) and elemental sulfur.
11. LAB is as useful in aquatic animals as terrestrial animals.
a) True
b) False
View Answer
Explanation: Lactic acid bacteria (LAB) according to several scientific reports are as useful and potent in aquatic organisms as in terrestrial organisms. There is however a growing need for new probiotics in aquaculture.
Sanfoundry Global Education & Learning Series – Marine Biotechnology.
To practice all areas of Marine Biotechnology, here is complete set of 1000+ Multiple Choice Questions and Answers.
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