Free Man and His Environment MCQs with Answers
382 Man and His Environment MCQs from Biology, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Ecosystems include biotic and abiotic components, food chains and webs, energy flow, nutrient cycles, populations and ecological relationships. Pollution and conservation cover air, water, soil and noise pollution, their effects on organisms, biodiversity loss, protected areas, sustainable resource use and methods for reducing environmental damage.
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Read the Man and His Environment notesFree MDCAT chapter notes with key terms382 questions · page 3 of 20
- A. Methanobacterium: Lactic acid
- B. Penicillium notatum: Acetic acid
- C. Saccharomyces cerevisiae: Ethanol
- D. Acetobacter aceti: Antibiotics
Explanation: S. cerevisiae is the primary industrial ethanol producer and is the most ethanol-tolerant natural yeast known, however, cannot metabolize…
Correct answer: Saccharomyces cerevisiae: Ethanol- A. (a)
- B. (b)
- C. (c)
- D. (d)
Explanation: Clostridium butylicum helps in the production of butyric acid. Candida lipolytic and Geotrichum candidum help in the production of lipases…
Correct answer: (b)- A. Methanogen
- B. Cyanobacteria
- C. Fucus sp.
- D. Chlorella sp.
Explanation: Methanogens like Methanobacterium are found in the rumen (a part of the stomach) of cattle.
Correct answer: Methanogen- A. Ulothrix
- B. Chlorella
- C. Spirogyra
- D. Polysiphonia.
Explanation: Chlorella is a single-celled chlorophycean alga with rich protein content.
Correct answer: Chlorella- A. Methane and CO2 only
- B. Methane, Hydrogen sulfide, and CO2
- C. Methane, Hydrogen sulfide, and O2
- D. Hydrogen sulfide and CO2
Explanation: The type of gases produced by microbial activity depends upon the microbes and the organic substrates they utilize.
Correct answer: Methane, Hydrogen sulfide, and CO2- A. Clostridium
- B. Saccharomyces
- C. Aspergillus
- D. Pseudomonas
Explanation: Aspergillus niger produces citric acid, Clostridium butylicum produces butyric acid, Saccharomyces is used for the commercial production…
Correct answer: Aspergillus- A. Saccharomyces cerevisiae
- B. Bacillus thuringiensis
- C. Streptococcus sp
- D. Trichoderma sp
Explanation: Biopesticides are those biological agents that are used for the control of weeds, insects, and pathogens.
Correct answer: Bacillus thuringiensis- A. Ethanol
- B. Streptokinase for removing clots from the blood vessels
- C. Citric acid
- D. Blood cholesterol-lowering statins.
Explanation: Statins are produced by the yeast Monascus purpureus which have been commercialized as blood cholesterol-lowering agents.
Correct answer: Blood cholesterol-lowering statins.- A. Penicillin
- B. Streptokinase
- C. Cyclosporin-A
- D. Statins.
Explanation: Streptokinase (Tissue Plasminogen Activator or TPA) is an enzyme obtained from the culture of some haemolytic bacterium Streptococcus…
Correct answer: Streptokinase- A. Spirulina
- B. Anabaena
- C. Frankia
- D. Tolypothrix.
Explanation: Azolla plays a very important role in rice production. Azolla and its nitrogen-fixing partner, Anabaena, have been used as green manure…
Correct answer: Anabaena- A. Trichoderma sp. against certain plant pathogens
- B. Nucleopolyhedro virus against white rust in Brassica
- C. Bt-cotton to increase cotton yield
- D. Lady bird beetle against aphids in mustard.
Explanation: A biological control being developed for use in the treatment of plant disease is the fungus Trichoderma.
Correct answer: Trichoderma sp. against certain plant pathogens- A. Butane
- B. Methane
- C. Propane
- D. Carbon dioxide.
Explanation: Biogas or gobar gas is a methane rich fuel gas produced by anaerobic breakdown or digestion of biomass with the help of methanogenic…
Correct answer: Methane- A. Two
- B. Three
- C. Four
- D. One
Explanation: Chikungunya is caused by the Chikungunya virus. Colostrum is the first breast milk of a mother which contains antibodies (especially IgA)…
Correct answer: Three- A. Has a high BOD as it contains both aerobic and anaerobic bacteria
- B. Is processed by aerobic and then anaerobic bacteria in the secondary treatment in Sewage Treatment Plants (STPs)
- C. When treated in STPs does not really require the aeration step as the sewage contains adequate oxygen
- D. Has a very high amount of suspended solids and dissolved salts.
Explanation: Sewage water can be purified by passing it through sewage treatment plants with the action of heterotrophic microorganisms.
Correct answer: Is processed by aerobic and then anaerobic bacteria in the secondary treatment in Sewage Treatment Plants (STPs)- A. Agrobacterium
- B. Rhizobium
- C. Nostoc
- D. Mycorrhiza
Explanation: Biofertilizers are organisms that enrich the nutrient quality of the soil.
Correct answer: Agrobacterium- A. Laughing gas
- B. Propane
- C. Mustard gas
- D. Marsh gas
Explanation: Marsh gas or methane gas is mainly produced by the activities of anaerobic bacteria in sewage.
Correct answer: Marsh gas- A. Azotobacter
- B. Azospirillum
- C. Rhizobium
- D. Nostoc
Explanation: Rhizobium is used as a biofertilizer for raising crops. Rhizobium japonicum forms a symbiotic association in the roots of the leguminous…
Correct answer: Rhizobium- A. Saccharomyces
- B. Clostridium
- C. Trichoderma
- D. Aspergillus
Explanation: Ethanol is commercially produced through a particular species of yeast Saccharomyces (Saccharomyces cerevisiae).
Correct answer: Saccharomyces- A. (a)
- B. (b)
- C. (c)
- D. (d)
Explanation: Cyclosporin A used as an immuno suppressive agent in organ-transplant patients, is produced by the fungus Trichoderma polysporum.
Correct answer: (b)- A. Sulphur rock
- B. Cattle yard
- C. Polluted stream
- D. Hot spring.
Explanation: Methanogens are any of various archaebacteria that produce methane; they include genera such as Methanobacillus and Methanothrix.
Correct answer: Cattle yard