Environmental Biotechnology Multiple Choice Questions on “Microalgal Culture – Closed and Semiclosed Outdoor Culture Systems”.
1. Which of the following can utilize the light source to promote growth of phototrophic microorganisms?
a) Algal blooms
b) Photo bioreactor
c) Stir tank bioreactor
d) Zooplankton
Answer: b
Clarification: Photo bioreactor is a type of bioreactor that can utilize the light source to promote growth of phototrophic organisms. Algal blooms cause the reduction in nutrient quality of the water which affects the biological life in water, however, Stir tank bioreactor is not used in this process. And zooplanktons are secondary consumers and they usually do not promote growth of phototrophic microorganisms.
2. Which of the following is an important step before further processing of the algal biomass grown in a photo bioreactor?
a) Harvesting
b) Centrifugation
c) pH change
d) Volume change
Answer: a
Clarification: Harvesting is an important step before further processing of the algal biomass grown in a photo bioreactor, Centrifugation is the harvesting method and not the process itself, whereas, pH change and volume changes are not the steps before further processing of the algal biomass.
3. How does the oil from the algal biomass is removed?
a) Solvent extraction
b) Water extraction
c) Gel extraction
d) Sieving
Answer: a
Clarification: Solvent extraction is the method which is used to remove the oil from the algal biomass, so, that it can be further processed, whereas, water extraction and gel extraction cannot be used to remove the oil from the algal biomass and sieving is a physical process of separation which cannot be used.
4. Which of the following organisms is not used in photo bioreactor?
a) Mosses
b) Microalgae
c) Purple bacteria
d) E. coli
Answer: d
Clarification: E. coli is not used in a photo bioreactor, also, this is considered as a pathogenic bacterium, whereas, microorganisms like Mosses, Microalgae, Purple bacteria are used in photo bioreactor which can generate biomass by the process of photosynthesis using light and carbon dioxide.
5. Water parameters change after being used in various industries, which of the following parameters is not altered in the end?
a) Physical
b) Chemical
c) pH
d) Volume
Answer: d
Clarification: The waste water has an altered chemical and or physical properties when it is used by various industries, also, pH is one parameter which is also altered when the water parameters change but the volume of the water remains the same.
6. What happens when the untreated water gets into the surface water which causes deterioration of water quality?
a) Volume
b) Biological characteristics
c) Temperature
d) Lipophilicity
Answer: b
Clarification: When untreated waste water is released into the surface water, it causes deterioration of water quality and hence, the biological characteristics of the water body is affected, whereas, temperature and volume of the water doesn’t really change the characteristic properties of water, chemical accumulation in the organism depends upon the lipid content and lipophilicity of an organism.
7. The variety of life forms gets affected due to untreated waste water.
a) True
b) False
Answer: a
Clarification: There is a huge diversity of life forms are found in water bodies, but untreated waste water has variety of life forms. The water bodies get affected by the untreated waste water when released to the environment into the surface water changing its properties.
8. Which of the following is not a result of the transformed primary productivity of water bodies?
a) Algal blooms
b) Adverse health effects
c) Reduction in water quality
d) Increase in water quality
Answer: d
Clarification: Algal blooms causes the reduction in nutrient quality of the water which affects the biological life in water, aquatic organism consumed by humans may cause adverse health effects, there is reduction in water quality, and all of these is caused due to altered primary productivity of water bodies, this never leads to increase in water quality.
9. The secondary pollution is caused due physical and chemical purification techniques.
a) True
b) False
Answer: a
Clarification: The physical and chemical methods are very useful in treating waste water and the process is very efficient in removing toxicants or pollutants but is very costly procedure and often causes secondary pollution.
10. Which of the following techniques is environment friendly and cost effective?
a) Physical
b) Chemical
c) Biological
d) Combination of physical and chemical
Answer: c
Clarification: Biological purification technique of waste water is environment friendly and cost effective whereas Chemical, Physical or a Combination of physical and chemical is efficient but can cause secondary pollution.
11. The decomposition of the organic compounds leads to conversion of released minerals into usable biomass.
a) True
b) False
Answer: a
Clarification: Biological purification technique uses catabolic reactions of microorganisms like bacteria, fungi, algae or other microorganisms for partial decomposition of the organic compounds which leads conversion of released minerals into usable biomass which is environment friendly.