Free MCQs & Online Quiz Practice for Exams

Q: A food web consists of

A) Interlocking food chains

B) Producers consumers and decomposers

C) A portion of a food chain

D) A set of similar consumers

Q: Predation helps to maintain balance in

A) Community

B) Population

C) Ecology

D) Ecosystem

Q: An ecological pyramid refers to the

A) Pyramid of energy

B) Pyramid of number

C) Pyramid of biomass

D) All of the above

Q: When the oxides of nitrogen (NO, NO₂) and sulphur (SO,SO₂, SO₃) interact with water vapours then the acids produced are

A) Acetic and Citric acid

B) Sulphuric and Nitric acid

C) Hydrochloric and Nitric acid

D) Sulphuric and Citric acid

Q: The process in which nitrates and nitrites are reduced to nitrogen gas by bacteria is

A) Assimilation

B) Denitrification

C) Ammonification

D) Nitrification

Q: The relationship between Rhizobium bacteria and leguminous plants is an example of

A) Parasitism

B) Mutualism

C) Commensalism

D) None of these

Q: The enzymes which are used to cut the DNA in specified sequences is

A) Ligase

B) Protease

C) DNAase

D) Endonuclease

Q: The DNA molecule in which the gene of interest is inserted for carrying to the target cell is

A) Transforming DNA

B) Carrier DNA

C) Phage DNA

D) Vector DNA

Q: Endonucleases used in genetic engineering are naturally present in

A) Bacteriophages

B) Bacterial cells

C) Plasmids

D) Blue green algae

Q: Fermenter is a machine which is basically used for

A) Increasing fermentation

B) Production of enzymes used in fermentation

C) Production of microorganisms

D) Making the conditions optimum

Q: Lactobacillus bulgaricus is a type of bacteria in the production of

A) Alcohol

B) Cheese

C) Yogurt

D) All of the above

Q: In a technique for genetic engineering rDNA stands for

A) Genetic makeup

B) Replicative DNA

C) Recombinant DNA

D) Retro DNA

Q: Interferons are chemicals which are used to

A) Kill viruses

B) Work as vaccine

C) Improve immunity

D) All of the above

Q: Which is a molecule containing DNA from two different organisms?

A) Vector DNA

B) DNA clone

C) Plasmid DNA

D) Recombinant DNA

Q: What term is used for inserting a healthy gene into a person who has a defective gene?

A) Cloning

B) Gene therapy

C) Vaccination

D) Fermentation

Q: Which of these can be used as a vector for inserting a gene into bacteria?

A) Plasmid

B) Algae

C) Yeast

D) E. coli

Q: Any substance that is used to modify the physiological systems for the benefit of the recipient is

A) Medicine

B) Narcotic

C) Vaccine

D) Drug

Q: Oral drugs are absorbed in the blood and are first taken to

A) Kidneys

B) Lungs

C) Liver

D) Brain

Q: Any preparation intended to produce immunity to a disease by stimulating the production of antibodies is

A) Drug

B) Antibiotic

C) Analgesic

D) Vaccine

Q: Drugs that calm patients down easing agitation and permitting sleep is termed as

A) Painkiller

B) Hallucinogen

C) Sedative

D) Narcotic