Environmental Biotechnology Multiple Choice Questions on “Cometabolic Degradation of Organic Pollutants”.
1. ____________ is the transformation of a substance without any nutritional benefit.
a) cometabolism
b) metabolism
c) glycogenesis
d) gluconeogenesis
Answer: a
Clarification: In presence of a growth substrate, the transformation of a substance without any nutritional benefit is called as Co metabolism, whereas, metabolism is the set of chemical reactions that take place in organisms, Gluconeogenesis is a metabolic process to produce sugars for catabolic reactions from any non-carbohydrate precursor.
2. Cometabolism can be used to convert a substance to a chemically modified form.
a) True
b) False
Answer: a
Clarification: Cometabolism is the simultaneous degradation of two compounds, where in the degradation of the secondary substrate depends on the presence of the primary substrate and hence, is used as a basis of bio-transformation and it can be used to convert a substance to a chemically modified form.
3. Microorganisms growing on a particular substrate can oxidize a second substrate called as __________
a) co substrate
b) sugar substrate
c) potassium substrate
d) calcium substrate
Answer: a
Clarification: When microorganisms growing on a particular substrate can oxidize a second substrate known as co substrate which is not assimilated but the product can be used as a substrate, whereas, sugar substrate, potassium substrate, calcium substrate are certain forms of substrate.
4. The pre-requisites for co-metabolic transformation are the enzymes and _____________
a) coal
b) oil
c) natural gas
d) co-factors
Answer: d
Clarification: The pre-requisites for co-metabolic transformation are the enzymes and synthesis of co-factors required for required for enzymatic reactions, whereas, Oil, Natural gas and coal cannot be used for metabolic transformation.
5. Which of the following substrate is not used by methanotrophic bacteria to oxidize methane?
a) Methanol
b) Formaldehyde
c) Methane
d) Carbon dioxide
Answer: d
Clarification: Methanotrophs or methanophiles are prokaryotes that can metabolise and convert the methane into by-products by using it as their only source of carbon and energy. Methanotrophic bacteria to oxidize methane to carbon dioxide via Methanol, Formaldehyde, Methane and not carbon dioxide itself.
6. Which of the following enzyme aids in the first step in methane oxidation?
a) Methanol
b) Formaldehyde
c) Methane mono oxygenase
d) Carbon dioxide
Answer: c
Clarification: Methane mono oxygenase enzyme acts as a catalyst in the first step in methane oxidation by attacking the inert methane, whereas, Methanol, Formaldehyde, carbon dioxide are not enzymes.
7. The high persistence of halogenated xenobiotic can be overcomed by anaerobic bacteria.
a) True
b) False
Answer: a
Clarification: To overcome the high persistence of halogenated xenobiotics, anaerobic bacteria plays an important role by converting them into simpler compounds by utilizing them as their sole carbon source and metabolizing them.
8. Which of the following factors doesn’t influence the rate of degradation by bacteria?
a) Microbial density
b) Microbial diversity
c) Association
d) Color
Answer: d
Clarification: The rate of degradation by bacteria is highly influenced by microbial density, diversity and association and not by Color because the color of the bacteria doesn’t influence the degradability capacity of the bacteria because it has nothing to do with the metabolism.