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

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

CSIR NET Life Science Previous Year Questions and Solution SECONDARY METABOLITESSECONDARY METABOLITES

37. Given below are various plant natural product and their basic structural unit: List I List II Natural Product Basic Unit A. Phenolics I. Five-carbon isoprene unit B. Alkaloids II.Glucose unit attached by O-β- D-glucosyl linkage C. Terpenoids III. Nitrogen containing D. Cyanogenic IV. Aromatic arene glycoside ring with OH group Which of the following options represent the correct match of natural product and the basic unit: (1) A-IV, B-I, C-III, D-II (2) A-III, B-II, C-I, D-IV (3) A-III, B-I, C-IV, D-II (4) A-IV, B-III, C-I, D-II

Basic Structural Units of Plant Natural Products

36. Artemisinin and Dhurrin belongs to respective groups of the plant natural compounds (1) Alkaloids and Terpenes (2) Flavonoids and Alkaloids (3) Cynogenic glycosides and Flavonoids (4) Terpenes and Cynogenic glycosides

Plant Defense Compound Classification

35. Which of the following is a plant secondary metabolite? (1) Kaurenoic acid (2) Abietic acid (3) Proline (4) Pyruvate

Kaurenoic Acid as a Plant Secondary Metabolite and Its Biological Role

34. Which one of the following secondary metabolites is characterized by the presence of a central carbon atom that is bound by a sulphur to a glycone group, and N by a nitrogen to a sulfonatedoxime group? (1) Alkaloids (2) Terpenes (3) Phenolics (4) Glucosinolates

Glucosinolate Chemical Structure

33.Which of the following class of plant secondary metabolite is present specially in the order Brassicales? (1) Glucosinolates (2) Alkaloids (3) Phenolics (4) Terpenoids

Glucosinolates as Signature Secondary Metabolites of the Brassicales Order

32. Which one of the following compound is NOT a part of alkaloid class of secondary metabolites? (1) Lignin (2) lndole (3)Tropane (4) Pyrroidine

Alkaloid Classification

31. β-thioglucosidases, also known as myrosinases, are the enzymes that are known to hydrolyse which one of the following plant natural products? (1) Glucosinolates (2) Terpenoids (3) Alkaloids (4) Phenolics

β-Thioglucosidase (Myrosinase)

30. Given below are some statements on secondary metabolites in plants. A. Glucosinolates are synthesized by elongation in the length of side chains of their precursor amino acids B. All terpenes produced in herbs and spices are sticky. oily liquids which reduces the palarability (edible value) of these plants. C. Cyanogenic glycosides are produced and stored in a toxic lour in plants and are therefore more effective in defense against invading pathogens and herbivores. D. The defense molecules,alkaloids (or their precursors), are gathered from plants and used by some insects for their own protection against predators. Which one of the following represents correct statements? (1) B and C only (2) A and B only (3) C only (4) A and D only

Key Defensive Secondary Metabolites in Plants

29. Phenyl ammonia Aase (PAL) and chalcone synthase (CHS) involved in biosynthesis of phenolic compound in plants. Following are some statements regarding the action of PAL and CHS: A. Substrate for PAL is phenyl alanine and for CS is chalcone B. PAL catalyze conversion of phenyl alanine to trans cinnamic acid C. PAL catalyze conversion of phenyl alanine to p-¬coumaric acid D. Coumaryl CoA is converted to chalcone by chalcone synthase Which of the following combinations of above statement is true? (1) A and B (2) A and C (3) B and C (4) B and D

Key Enzymes in Phenolic Biosynthesis: PAL and CHS Functions Explained

28. Given below are the list of plant derived alkaloids and their uses in modern medicine. Alkaloids Uses A. Caffeine i. Antineoplastic used to treat leukemia and other cancers B. Morphine ii. Traditional anti- malaria agent C. Quinine iii. Powerful Narcotic analgesic D. Vincristine iv. Widely used central nervous syntem stimulant Which one of the following options represents all correct matches ? (1) A (iii) B (iv) C(ii) D(i) (2) A (iii) B (iv) C(i) D(ii) (3) A (iv) B (i) C(iii) D(ii) (4) A (iv) B (iii) C(ii) D(i)

Important Plant Alkaloids and Their Medicinal Uses

27. Several plants produce metabolites with important medicinal properties and have been extensively used in traditional medicine across the world. Many of these compounds can now be purified or synthesized and are used in modern medicine. Given below is a list of metabolites, their plant source and medicinal use Metabolite Plant Source Medicine Use A. Digitoxin i. Artemisia Q. Aspirin annua B. Salicin ii. Papaver R. Anti-malarial somniferum C. Morphine iii. Digitalis S. Cardiac purpurea ailment D. Artemisin iv. Willow tree T. Narcotic analgesic Which one of the following options is the most appropriate match of the compound with its plant source and use? (1) A-iii-R; B-i-T; C-iv-Q; D-ii-S (2) A-iv-Q; B-iii-R; C-ii-S; D-i-T (3) A-ii-T; B-iii-S; C-i-R; D-iV-Q (4) A-iii-S; B-iv-Q; C-ii-T; D-i-R

Medicinal Plant Metabolites

26. The plant species which produces both oil and dye (1) Sesamum indicum (2) Conovalia glodicosa (3)Carthamus tinctorius (4) Riccinus cumminis

Carthamus tinctorius: A Dual-Purpose Plant Producing Oil and Natural Dye

25. The main alkaloid obtained for Dioscoreo deltoids is (1) Diosgenin (2) Atropine (3) Quinone (4) Serpentine

Diosgenin as the Key Bioactive Compound from Dioscorea deltoidea

24. Which anti-cancerous drug is obtained from Catharanthus roseus (1) Taxol (2) Vincristine (3) Colchicine (4) Serpentine

Vincristine: The Anti-Cancer Vinca Alkaloid from Catharanthus roseus

23. The anti-cancerous drug vincristine is obtained frorn- (1) Catharanthus (2) Taxus (3) Aribidposis (4) Cochicum

Catharanthus roseus: The Botanical Source of the Anticancer Drug Vincristine

22. Reserpine, a drug used for treating mental disorders and high blood pressure, is extracted from the roots of which of the following plant species? (1) Ferulo (2) Rouwolfro (3) Digitalis (4) Atropa

Rauwolfia serpentina: The Natural Source of the Drug Reserpine

21.Spermidine represents which of the following group of compounds. (1) jasmonic acid (2) polyamine (3) auxin (4) strigolactone

Spermidine: A Key Polyamine Regulating Plant Growth and Cellular Functions

20. Which of the following is a mismatch between the plant drug and its source? (1) Codeine – Papaver Somniferum (2) Vinblastine – Catharanthus roseus (3) Quinine – Cinchona lefgeriana (4) Digitalin – Artemisia annua

Mismatches in Plant-Derived Drugs and Their Botanical Sources

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 ‘ tyrosine – orphine’ (3) ‘Tyrosine – quinine ‘ and ‘tryptophan- orphine’ (4) ‘Ornithine – quinine’ and ‘ ornithine aspartate – nicotine’

Amino Acid Precursors of Nicotine and Quinine: Insights into Alkaloid Biosynthesis

18. Dirigent proteins predominantly play an important role in biosynthesis of: (1) lignans (2) alkaloids (3) Terpenoids (4) amino acids

Role of Dirigent Proteins in the Stereoselective Biosynthesis of Lignans in Plants

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 (3) Mevalonic acid pathway (4) Methylerythritol pathway

Biosynthesis of Phenylalanine via Shikimic Acid Pathway in Plants

16. Which of the following is produced in phenyl propanoid pathway? (1) Phenolics (2) Carotenes (3) Alkaloids (4) Terpenes

Phenylpropanoid Pathway as the Source of Plant Phenolic Secondary Metabolites

15. The precursor for most of phenolic secondary metabolites is (1) Phenyl alanine (2) Isopentyl pyrophosphate (3) Mevalonate (4) Geranyl phosphate

Phenylalanine as the Precursor of Plant Phenolic Secondary Metabolites

14. 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 is highly susceptible to a specific fungal pathogen. To interpret this counter. intuitive observation, the researcher hypothesizes that the fungal pathogen has higher level of A. β-glucosidase activity B. formamide hydrolyase activity C. cytochrorne P-450 enzyme D. cyanide-resistant, alterative oxidase activity Which one of the following combinations of the above hypotheses is correct? (1) A and B (2) B and C (3) C and D (4) B and D

Fungal Pathogen Detoxification Mechanisms Against Plant Cyanogenic Glycoside Defenses

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 oil of the Asian neem tree. D. Taxol is a diterpene derivative used in cancer treatment. Which of the following options represents the combination of all correct statements? (1) A and B (2) C and D only (3) A, B and D (4) B, C and D

Key Natural Terpenes: Artemisinin, Azadirachtin, Taxol, and Their Biological Roles

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 and are synthesized by shikimic acid pathway. (C) Phenolic compounds are synthesized by shikimic acid pathway and mevalonic acid pathway. (D) Both alkaloids and terpenes are synthesized by mevalonic acid pathway and MEP pathway. Which one of the following combinations of the above statement is true? (1) A and D (2) A and C (3) B and C (4) B and D

Biosynthesis Pathways of Terpenes, Phenolics, and Alkaloids in Plant Secondary Metabolism

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 ii. P450 B. Repetitive monooxygenases addition of C5 units C. Formation iii. HMG-COA of the basic synthase terpenoid skeletons D. Modification iv. Prenyltransferases of terpenoid skeletons (1) A-i, B-iii, C-iv, D-ii (2) A-ii, B-iii, C-i, D-iv (3) A-i, B-ii, C-iii, D-iv (4) A-iii, B-iv, C-i, D-ii

Four Enzymatic Stages of Terpenoid Biosynthesis in Plants

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 infected by pathogens. B. Terpenes, the largest class of secondary metabolite, are synthesized by methyl erythritol phosphate(MEP) pathway and shikimic acid pathway. C. The mast abundant classes of phenolic compounds in plants are derived from phenylalanine. D. Alkaloids are nitrogen containing secondary metabolites in plants. Which one of the following combinations of the above statements is correct? (1) A, B and C (2) B, C and D (3) A, C and D (4) A, B and D

Plant Secondary Metabolites: Biosynthesis and Role of Terpenes, Phenolics, and Alkaloids

9. The gene encoding for mevalonate-3-kinase is disrupted in a certain plant. Which one of the following staternents concerning the above plant is correct? (1) Mevalonic acid 3,5-biphosPhate will be synthesized, while there will be no synthesis of Mevalonic acid 5-phosphate. (2) Mevalonic acid 3,5-biphosphate and Isopentenyl diphosphate will be synthesized. (3) There will be no synthesis of Mevalonic acid 3, 5- biphosphate but Mevalonic acid will be synthesized. (4) Aceto acetyle-coA and Mevalonic acid will not be synthesized.

Effects of Mevalonate-3-Kinase Disruption on Mevalonate Pathway and Isoprenoid Biosynthesis in Plants

8. In terpene biosynthesis pathways, three acetyl-CoA are joined together stepwise to form mevalonic acid. mevalonic acid to form isopentenyl diphosphate or Which one of the following three- steps is required by isopentenyl pyrophosphate (IPP)? (1)Pyrophosphorylation, decarboxylation, and dehydration. (2)Alkylation, pyrophosphorylation and decarboxylation. (3) Methylation, dehydration and alkylation. (4) Phosphorylation, carboxylation and methylation.

Key Steps in Isopentenyl Pyrophosphate Biosynthesis from Mevalonic Acid

7. Following are certain statements regarding secondary metabolites found in plant: A. All terpenes are derived from a six carbon element. B. Alkaloids are nitrogen containing compounds. C. Pyrethroids, a monoterpene ester found in the leaves and flower of Chrysanthemum species, show insecticidal activity. D. Limonoids are groups of alkaloids and have anti¬herbivoral activity. Which one of the following combinations of above statements is correct? (1) A and B (2) A and D (3) B and C (4) C and D

Key Plant Secondary Metabolites

5. Following are a few statements regarding the structure of terpenes: A. Isopentenyl diphosphate and farnesyl diphosphate are monoterpene and sesquiterpene, respectively. B. Squalene and geranyl diphosphate are triterpene and monoterpene, respectively. C. Dimethylallyl diphosphate have 10 and 20 carbons, respectively. D. Diterpenes have 20 carbons, whereas sesquiterpenes have 15 carbons Which combination of the above statements is correct? (1) A and B (2) B and D (3) A and C (4) C and D

Structural Classification and Carbon Number of Terpenes

4. Which of the following acts as a branch point for the bioosynthesis of sesquiterpene and triterpenes? (1) Farnesyl pyrophosphate (2) Geranyl pyrophosphate (3) Isopentyl pyrophosphate (4) Hydroxyrnethylglularyl -CoA

Farnesyl Pyrophosphate: The Branch Point in Sesquiterpene and Triterpene Biosynthesis

Which one of the following combinations of secondary metabolite biosynthetic pathway result in the biosynthesis of terpenes? (1) Mevalonic acid and MEP pathways (2) Malonic acid and MEP pathways (3) Shikimik acid and Malonic acid pathway (4) Shikimik acid and Mevalonic acid pathways

The Mevalonic Acid and MEP Pathways: Dual Routes for Plant Terpene Biosynthesis

2. The following statements are made regarding secondary metabolites of plants: A. All secondary metabolites are constitutively produced in all cells of a plant during its entire life B. They serve as signals to help the plant survive adverse conditions C. They may be volatile compounds D. They contribute to flower colour Which one of the following options represents a combination of correct statements? (1) A, B and C (2) B, C and D (3) A, C and D (4) A, B and D

Roles and Characteristics of Plant Secondary Metabolites in Stress and Development

1. Among the following which is a terpene (1) Chlorophyll (2) Lycopene (3) Xanthophyll (4) Carotene

Carotene as a Representative Terpene in Plant Pigments

11. Gibberllin treatment to grape plants leads to (1) Fruit ripening (2) Seedless fruit (3) Cell division (4) Leaf fall

Effect of Gibberellin Treatment on Grape Plant

Latest Courses

IIT JAM / CUET- PG

IIT JAM / CUET- PG

Are you aspiring to crack the IIT JAM Biotechnology exam with flying colors? Choosing the right coaching institute is crucial for your success. Let's Talk Academy (LTA) has established itself as the best coaching institute for IIT JAM Biotechnology, helping students achieve their dreams through expert guidance, structured study material, and personalized mentorship.

CSIR UGC NET Life Science Course

CSIR UGC NET Life Science Course

Let's Talk Academy is the number one CSIR NET Life Science coaching in Jaipur for Life Science. At Let's Talk Academy, you can be sure to get the right coaching strictly in adherence to the CSIR NET Life Science course.  CSIR NET Life Science is an exam that requires in-depth knowledge, consistent practice, and the right guidance to crack. If you are looking for a place where you can get the best CSIR NET Life Science coaching, you are at the right place.

ICMR JRF Life Science

ICMR JRF Life Science

If you are serious about cracking the ICMR Life Science JRF exam, Let’s Talk Academy is your ultimate destination. Join now and take the first step toward a successful research career!