51.

What is true about Bt toxin

• Bt protein exists as active toxin in the Bacillus.

• The activated toxin enters the ovaries of the pest to sterilise it and thus prevent its multiplication.

• The concerned Bacillus has antitoxins.

• The inactive protoxin gets converted into active form in the insect gut

Wine and beer are produced directly by fermentation whereas brandy and whisky require both fermentation and distillation. This is because

• fermentation is inhibited at an alcohol level of 10-18%

• distillation prolongs storage

• distillation improves quality

• distillation purifies the beverage.

Which of the following is not a characteristic of pBR322 vector

• It is the first artificial cloning vector constructed in 1977 by Boliver and Rodriguez.

• It is the most widely used, versatile and easily manipulated vector.

• It has two antibiotic resistance genes, tet^r and amp^r.

• It does not have restriction site for Sal I.

Which one of the following immune system components does not correctly match with its respective role

• Interferons - secreted by virus-infected cells and protect non-infected cells from further viral infection

• B-lymphocytes-produces antibodies in response to pathogens into blood to fight with them

• Macrophages-mucus secreting cells that trap microbes entering in the body

• IgA-present in colostrum in early days of lactation and protect infant from diseases

Assertion: In a pedigree analysis, <5> represents five unaffected offsprings.

Reason: In a pedigree analysis, the offsprings are numbered with arabic numerals (1, 2, 3 .....) and a generation is numbered with roman numerals (I, II, III...).

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion: AIDS and hepatitis B are sexually transmitted diseases.

Reason: There is no permanent cure for both of them

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion: One codon may code for more than one amino acid.

Reason: A codon is degenerate and ambiguous.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion: Interspecific competition is the only potent force in organic evolution.

Reason: Unexceptionally two closely related species competing for the same resources cannot co-exist indefinitely

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion: GM crops can affect human health by causing allergic reactions.

Reason: Transgenes in commercial crops can endanger native species e.g., the Bt toxin gene expressed in pollen might endanger pollinators like honeybees.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion: Secondary air pollutants are formed by interaction among the primary pollutants and are more toxic.

Reason: DDT is a secondary air pollutant.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.