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Q.1
Highest number of antibiotics are produced by ...[ MPPMT 2009]
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a) Bacillus
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b) Penicillium
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c) Streptomyces
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d) Cephalosporium
Explanation
Streptomycetes are characterised by a complex secondary metabolism. They produce over two-thirds of the clinically useful antibiotics of natural origin e.g., neomycin, cypemycin, grisemycin, bottromycins and chloramphenicol. Streptomyces griseus produces more than 41 antibiotics while Bacillus subtilis can give about 60 antibiotics Answer:(c)
Q.2
Match List-I with List-II [ NEET 2021] Choose the correct answer from the option given below
List – I
List – II
a) Aspergillus niger
i) Acetic acid
b) Acetobacter aceti
ii) Lactic acid
c) Clostridium butylicum
iii) Citric acid
d) Lactobacillus
iv) Butyric acid
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a) a – iv, b – ii, c—i, d – ii
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b) a – iii, b – i, c—iv, d – ii
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c) a – i, b – ii, c—iii, d – iv
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d) a – ii, b – iii, c—i, d – iv
Explanation
Aspergillus niger (a fungus) of citric acid, Acetobacter aceti (a bacterium) of acetic acid; Clostridium butylicum (a bacterium) of butyric acid and Lactobacillus (a bacterium) of lactic acid. Reference NCERT text book 12th Page 183, 10.2.3 Chemicals, Enzymes and other Bioactive Molecules Answer:(b)
Q.3
Which of the following is put into Anaerobic sludge digester for further sewage treatment? [NEET 2020]
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a) Effluents of primary treatment
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b) Activated sludge
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c) Primary sludge
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d) Floating debris
Explanation
Activated sludge is take into anaerobic sludge digester. Here, anaerobic microbes act upon organic matter to first produce monomers and then organic acids. Methanogens then convert organic acids into a mixture of gases like methane, hydrogen sulphide and carbon dioxide. Answer:(b)
Q.4
Match the following organisms with the products they produce ..[NEET 2019]
(a)
Lactobacillus
(i) Cheese
(b)
Saccharomyces
(ii) Curd cerevisiae
(c)
Aspergillus niger
(iii) Citric Acid
(d)
Acetobacter aceti
(iv) Bread
- -
(v) Acetic Acid
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a) a → ii; b → iv; c → v; d → iii;
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b) a → ii; b → iv; c → iii; d → v;
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c) a → iii; b → iv; c → v; d → i;
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d) a → ii; b → i; c → iii; d → v;
Explanation
Microbes are used in production of several household and industrial products – Lactobacillus – Production of curd Saccharomyces cerevisiae – Bread making Aspergillus niger – Citric acid production Acetobacter aceti – Acetic acid Answer:(b)
Q.5
Select the correct group of biocontrol agents. [NEET 2019]
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a) Bacillus thuringiensis, Tobacco mosaic, virus, Aphids
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b) Trichoderma, Baculovirus, Bacillus thuringiensis
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c) Oscillatoria, Rhizobium, Trichoderma
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d) Nostoc, Azospirillium, Nucleopolyhedrovirus
Explanation
Fungs Trichoderma, Baculoviruses (NPV) and Bacillus thuringiensis are used as biocontrol agents. Rhizobium, Nostoc, Azospirillum and Oscillatoria are used as biofertilisers, whereas TMV is a pathogen and aphids are pests that harm crop plants. Answer:(b)
Q.6
Which of the following is a commercial blood cholesterol lowering agent? [NEET 2019]
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a) Cyclosporin A
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b) Statin
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c) Streptokinase
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d) Lipases
Explanation
Statin is obtained from a yeast (Fungi) called Monascus purpureus. It acts by competitively inhibiting the enzyme responsible for synthesis of cholesterol. Answer:(d)
Q.7
Which of the following can be used as a biocontrol agent in the treatment of plant disease? [NEET 2019]
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a) Trichoderma
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b) Chlorella
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c) Anabaena
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d) Lactobacillus
Explanation
Fungus Trichoderma is a biological control agent being developed for use in the treatment of plant diseases. Answer:(a)
Q.8
Conversion of milk to curd improves its nutritional value by increasing the amount of .... [NEET 2018]
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a) Vitamin B12
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b) Vitamin A
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c) Vitamin D
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d) Vitamin E
Explanation
Answer:(a)
Q.9
A river with an inflow of domestic sewage rich in organic waste may result in :- …[AIPMT-2016]
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a) Drying of the river very soon due to algal bloom.
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b) Increased population of aquatic food web organisms.
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c) An increased production of fish due to biodegradable nutrients.
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d) Death of fish due to lack of oxygen.
Explanation
Organic matter readily decomposes due to bacteria and other micro-organism. These micro-organism consumes lot of dissolved oxygen. This causes mortality of fishes and other aquatic creatures. Answer:(d)
Q.10
Match Column –I with Column–II and select the correct option using the codes given below …[NEET 2016]
Column-I
Column-II
(a) Citric acid
(i) Trichoderma
(b) Cyclosporin A
(ii) Clostridium
(c) Statins
(iii) Aspergillus
(d) Butyric acid
(iv) Monascus
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a) (a) → i ; (b) → iv ; (c) →ii ; (d) →iii
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b) (a) →iii ; (b) →iv ; (c) →i; (d) → ii
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c) (a) → iii; (b) → i ; (c) →ii; (d) → iv
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d) (a) →iii; (b) → i ; (c) →iv ; (d) → ii
Explanation
Citric acid is produced by Aspergillus niger. Butyric acid is produced by Clostridium butyricum. Statins are synthesized by activity of yeast Monascus purpureus. Cyclosporin A is synthesized by fungus Trichoderma polysporum. Answer:(d)
Q.11
Match the following columns and select the correct option. [NEET 2020]
Column-I
Column-II
(a) Clostridium butylicum
(i) Cyclosporin-A
(b) Trichoderma polysporum
(ii) Butyric Acid
(c) Monascus purpureus
(iii)Citric Acid
(d) Aspergillus niger lowering agent
(iv) Blood cholesterol
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a) a → i; b → ii; c → iv; d → iii;
0%
b) a → iv; b → iii; c → ii; d → i;
0%
c) a → iii; b → iv; c → ii; d → i;
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d) a → ii; b → i; c → iv; d → iii;
Explanation
Clostridium acetobutylicum was metabolically engineered for highly selective butyric acid production. a → ii Cyclosporine A is widely produced by submerged fermentation of aerobic fungi identified as Trichoderma polysporum. b → i Manescus purpureus is a yeast used commercially in the production of blood cholesterol lowering statins. c → iv Aspergillus niger is a fungal microbe of great industrial importance. This mold is used extensively in the production of citric acid and in the production of several enzymes such as amylases, pectinases, and proteases. d → iii Answer:(d)
Q.12
Which of the following is correctly matched for the product produced by them? ….[NEET- 2017]
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a) Acetobacter aceti : Antibiotics
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b) Methanobacterium : Lactic acid
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c) Penicillium notatum : Acetic acid
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d) Saccharomyces cerevisiae : Ethanol
Explanation
Saccharomyces cerevisiae is commonly called Brewer’s yeast. It causes fermentation of carbohydrates producing ethanol. Acetobacter aceti produces acetic acid from ethanol. Methanobacterium produces methane and is present in cow's gut. Penicillium notatum is the first Penicillium fungi used for the isolation of penicillin antibiotics, which is used for the treatment of Gram-positive bacteria. Answer:(d)
Q.13
Select the mismatch : ….[NEET- 2017]
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a) Frankia – Alnus
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b) Rhodospirillum – Mycorrhiza
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c) Anabaena – Nitrogen fixer
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d) Rhizobium – Alfalfa
Explanation
Rhodospirillum is anaerobic, free living nitrogen fixer.Mycorrhiza is a symbiotic relationship between fungi and roots of higher plants. Answer:(b)
Q.14
Match the following list of microbes and their importance : [ ReAIPMT 2015]
(a) Saccharomyces cerevisiae
(i) Production of immunosuppressive agents
(b) Monascus purpureus
(ii) Ripening of Swiss cheese
(c) Trichoderma polysporum
(iii) Commercial production of ethanol
(d) Propionibacterium sharmanii
(iv) Production of blood cholesterol lowering agent
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a) (a) → (iii);(b) → (i);(c) → (iv) ;(d) → (ii)
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b) (a) →(iii); (b) →(iv);(c) → (i);(d) → (ii)
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c) (a) →(iv)(b); → (iii);(c) → (ii);(d) → (i)
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d) (a) →(iv)(b); → (ii);(c) → (i);(d) → (iii)
Explanation
Saccharomyces cerevisiae is commonly called Brewer’s yeast. It causes fermentation of carbohydrates producing ethanol. Statins are synthesized by activity of yeast Monascus purpureus. It is used for lowering LDL cholesterol level. Fungus Trichoderma polysporum produces cyclosporin A. Cyclosporin A has immunosuppressive property as it inhibits activation of T cell response to transplanted organs. Swiss cheese has large holes produced by carbon dioxide given out by bacterium Propionibacterium sharmanii. Answer:(b)
Q.15
Azotobacter and Bacillus polymyxa are ... [ CBSE 1996]
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a) Decomposers
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b) Non symbiotic nitrogen fixers
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c) Symbiotic nitrogen fixers
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d) Pathogenic bacteria
Explanation
Paenibacillus polymyxa, also known as Bacillus polymyxa, is a Gram-positive bacterium capable of fixing nitrogen. It is found in soil, plant tissues, marine sediments and hot springs Answer:(b)
Q.16
During cellulose fermentation by anaerobic bacteria in rumen and reticulum, cellulose is mainly changed to .. [ BHU 2012]
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a) CO2
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b) Ethyl alcohol
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c) Lactic acid
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d) Volatile fatty acids
Explanation
During cellulose fermentation by anaerobic bacteria in rumen and reticulum, cellulose is mainly changed to volatile fatty acids Answer:(d)
Q.17
Devine and Collego are two trade names for ...[ Pb PMT 2002]
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a) Biofungicide
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b) Bioherbicides
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c) Biofertilizers
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d) Natural insecticides
Explanation
Devine and Collego derived from the fungal spores. Devine was first mycoherbicide and another mycoherbicide was Collego. Its controls growth of the milk weed vines in citrus orchards and growth the northern jointvetch growing in rice fields respectively. Answer:(b)
Q.18
Which one is used in the production of alcohol/ ethanol? ...[ CBSE 2000]
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a) Saccharomyces cerevisiae
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b) Torulopsis utilis
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c) Clostridium botulinum
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d) Leuconostoc citrovorum
Explanation
Saccharomyces cerevisiae also known as brewer’s yeast is used in production of alcohol. Torulopsis utilis is a species of yeast. It is an inactive form of yeast and widely used as a flavouring agent in processed foods and pet foods. Clostridium botulinum is a bacterium that produces dangerous toxins (botulinum toxins) under low-oxygen conditions. Botulinum toxins are one of the most lethal substances known. Botulinum toxins block nerve functions and can lead to respiratory and muscular paralysis. Leuconostoc species are heterofermentative, Gram-positive cocci. They produce flavor compounds such as diacetyl and acetoin, and some strains produce exopolysaccharides. Leuconostoc mesenteroides subsp. cremoris is used in the production of cottage and cream cheese and cultured milks. Answer:(a)
Q.19
Aquatic fern which is an excellent biofertilizer ... [ Odisha 2008]
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a) Salvinia
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b) Azolla
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c) Marsilea
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d) Pteridium
Explanation
Azolla pinnata is a small aquatic fern inoculated to rice fields of south-east Asian countries. It contains symbiont Anabaena in its leaf cavities. Increase in yield is more than 50%. Answer:(b)
Q.20
Baker's yeast is ... [ HPPMT 2011]
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a) S. cerevisiae
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b) S. ludwigii
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c) S. octosporus
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d) Schizosaccharomyces
Explanation
Baker's yeast is of the species Saccharomyces cerevisiae, and is the same species (but a different strain) as the kind commonly used in alcoholic fermentation, which is called brewer's yeast. Baker's yeast is the common name for the strains of yeast commonly used in baking bread and other bakery products, serving as a leavening agent which causes the bread to rise by converting the fermentable sugars present in the dough into carbon dioxide and ethanol. Answer:(a)
Q.21
Farmers have reported 50% higher yield of Rice by using biofertilizer ... [ CBSE 1998]
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a) Azolla pinnata
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b) Legume - Rhizobium symbiosis
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c) Cyanobacteria
0%
d) Mycorrhiza
Explanation
Azolla pinnata is a small aquatic fern inoculated to rice fields of south-east Asian countries. It contains symbiont Anabaena in its leaf cavities. Increase in yield is more than 50%. Answer:(a)
Q.22
Which bacterium is used extensively as biopesticide? [ W.B. 2008]
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a) Bacillus subtilis
0%
b) Streptococcus lactis
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c) Bacillus thuringiensis
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d) Lactobacillus acidophilus
Explanation
Bacillus subtilis is used in synthesis of enzyme protease. Streptococcus lactis produces lactic acid. Bacillus thuringiensis synthesize different insecticidal proteins named Cry, Vip, and Cyt that are able to kill different insect orders, or nematodes. These proteins have been extensively used in insect control practices in agriculture. Lactobacillus acidophilus help restore the normal balance of intestinal bacteria. This product has been used for diarrhea and other stomach/intestinal problems. Answer:(c)
Q.23
Terramycin is got from ... [ CPMT 1998]
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a) Streptomyces griseus
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b) S. venezuelae
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c) S. ramosus
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d) S.aureofaciens
Explanation
Terramycin is antibiotics used for intestinal and urinary infections. It is synthesized from Streptomyces aureofaciens. Answer:(c)
Q.24
"Gray biotechnology" is ... [ AMU 2010]
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a) Aquatic process
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b) Agricultural process
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c) Industrial process
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d) Medical process
Explanation
Colour
Area of biotech activities
Red
Health, medical
Yellow
Food, nutritional science
Blue
Aquaculture, coastal, marine
Green
Agricultural, environmental
White
Gene-based bioindustries
Grey
Classical fermentation and bioprocess technology
Answer:(c)
Q.25
Nitrogen fixation is ... [ EAMCET 1996]
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a) Nitrogen → Ammonia
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b) Nitrogen → Nitrates
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c) Nitrogen → Amino acids
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d) Both A and B
Explanation
Nitrogen fixation, any natural or industrial process that causes free nitrogen (N2), which is a relatively inert gas plentiful in air, to combine chemically with other elements to form more-reactive nitrogen compounds such as ammonia, nitrates, or nitrites. Answer:(d)
Q.26
In paddy fields, biological nitrogen fixation is chiefly brought about by ... [ Wardha 2011]
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a) Cyanobacteria
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b) Green algae
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c) Mycorrhiza
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d) Rhizobium
Explanation
Cyanobacteria are autotrophic microbes widely distributed in aquatic and terrestrial environments many of which can fix atmospheric nitrogen, e.g. Anabaena, Nostoc, Oscillatoria, etc. In paddy fields, cyanobacteria serve as an important biofertiliser. Blue green algae also add organic matter to the soil and increase its fertility Answer:(a)
Q.27
Penicillin is got from ...[ MPPMT 1997]
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a) Streptomyces griseus
0%
b) Penicillium chrysogenum
0%
c) Penicillium griseofulvum
0%
d) Aspergillus fumigatus
Explanation
Penicillin is derived from Penicillium chrysogenum and Penicillium notatum. Answer:(b)
Q.28
Which is false about antibiotics? ...[ CBSE 1996]
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a) Cure all diseases
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b) Produced by microorganisms
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c) Produce allergy in some person
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d) Coined by Waksman(1942)
Explanation
An antibiotics is a substance produced by a microorganism which in low concentration inhibits the growth and metabolic activity of pathogens without harming the host. The term was coined by Waksman(1942). Antibiotics work against bacteria and hence cannot cure all disease Answer:(a)
Q.29
Which one is a neem product used as insect repellent ... [ MPPMT 2012]
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a) Rotenone
0%
b) Azadirachta
0%
c) Parathion
0%
d) Endrin
Explanation
Azadirachtin, a chemical compound belonging to the limonoid group, is a secondary metabolite present in neem seeds. It is natural insecticide and is used as repellent. Answer:(b)
Q.30
Distillation of wine is necessary as it ... [ CPMT 1996]
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a) Decreases toxicity
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b) Increases duality
0%
c) Prevents further fermentation and spoiling of wine
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d) Has no action on nature of wine
Explanation
In case of wines 10-27% alcohol content is achieved through refinement and concentration. There is no need for distillation. Distillation is carried out in other cases like gin, brandy, rum. Distillation is done to increase concentration of alcohol content. Thus, distillation will have no action on nature of wine. Answer:(c)
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