Tag: CSIR NET Life Science Previous Year Questions and Solution SECONDARY METABOLITES

19. Which one of the following pairs of precursor amino acid and alkaloid is correct? (1) ‘Ornithine  aspartate – nicotine’ and ‘tryptophan – quinine’. (2) ‘Ornithine – nicotine’ and ‘ […]

Dirigent proteins predominantly play an important role in biosynthesis of: (1) lignans                   (2) alkaloids (3) Terpenoids         (4) amino acids Correct answer: (1) lignans Explanation: Dirigent proteins play a crucial role […]

17 Phenylalanine, a precursor of most of the phenolics in higher plants is a product of which one of the following pathways? (1) Shikimic acid pathway (2) Malonic acid pathway […]

16. Which of the following is produced in phenyl propanoid pathway? (1) Phenolics      (2) Carotenes (3) Alkaloids                (4) Terpenes Correct answer: (1) Phenolics Explanation: The phenylpropanoid pathway leads to the production […]

The precursor for most of phenolic secondary metabolites is (1) Phenyl alanine (2) Isopentyl pyrophosphate (3) Mevalonate (4) Geranyl phosphate Correct answer: (1) Phenyl alanine Explanation: Phenylalanine is the primary precursor […]

Certain plant species produce cyanogenic glycosides to protect them from pathogens. A researcher has identified a variant of such a plant that has higher level of cyanogenic glycoside yet it […]

13. statements are made regarding natural product, terpenes. A. monoterpenes are five-carbon compounds. B. The anti-malarlal         drug, artemisinin is a sesquiterpene. C. Azadirachtin is a triterpene derivative from the seed […]

12. Following are some statements for synthesis of secondary metabolites in plants. (A) Terpenes are synthesized by shikimic acid pathway and mevalonic acid pathway. (B) Alkaloids are nitrogen containing compounds […]

11. Plants are known to synthesize more than 30,000 terpenoids, involving four stages of biosynthesis. Column X                Column Y A. Biosynthesis       i. Terpene of two basic five        synthases carbon unit            […]

10. Secondary metabolites are diverse array organic compounds in plants. The following are certain statements about secondary metabolites: A. They protect plants against being eaten by herbivores and against being […]