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#glyphosate

3 public questions tagged with this topic.

Glyphosate inhibits which enzyme?

Glyphosate N-phosphonomethyl glycine inhibits key enzyme of aromatic amino acid pathway. 5-enolpyruvylshikimate-3-phosphate synthase normally condenses shikimate-3-phosphate and phosphoenolpyruvate to EPSP in chloroplast stroma, penultimate step of shikimate pathway. Glyphosate mimics PEP, occupying PEP binding site in EPSPS-S3P complex forming stable dead-end complex preventing enolpyruvyl transfer. Plants cannot synthesize chorismate, precursor of phenylalanine, tyrosine, tryptophan, causing accumulation of shikimate, depletion of aromatic amino acids, cessation of protein synthesis, and dea

Ref: Steinrücken Biochem Biophys Res Commun 1980 glyphosate EPSPS; Funke PNAS 2006 Roundup Ready molecular basis; NCBI NBK22387; https://www.pnas.org/doi/10.1073/pnas.0603638103

Glyphosate inhibits which pathway?

Answer: B) Shikimate. For PLANT SEC METABOLITES, remember the key idea and you’ll land on this option; the distractors usually swap cause and effect or confuse similar terms. Avoid: A) MEP; C) Malonate; D) MVA. Name the process first, then pick the option that describes it — don’t reverse cause and effect.

Ref: Best CSIR NET Plant Physiology books: Master Unit 6 with Taiz & Zeiger and Salisbury & Ross. Crack Part C experimental questions with top textbooks.

Glyphosate kills plants mainly because it is:

Go with B — Phloem mobile. Under PHLOEM TRANSLOCATION, this is the standard explanation you’d use in class: it names the real driver or definition, while the rest are nearby but wrong. Not these: A) Xylem mobile; C) Non-translocated; D) Volatile. When two options sound similar, choose the one that matches the textbook definition most tightly.

Ref: Best CSIR NET Plant Physiology books: Master Unit 6 with Taiz & Zeiger and Salisbury & Ross. Crack Part C experimental questions with top textbooks.