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Phytohormone ALL PYQS

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30 questions

Conversion of IBA to IAA occurs via β‑oxidation in:

Pick C: Peroxisomes. Thinking through Phytohormone ALL step by step rules out the lookalikes and leaves Peroxisomes. Skip these: A) Mitochondria; B) Plastids; D) Cytosol. For hormones and genes, match the molecule or gene to its real role, not a neighboring pathway.

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

Auxin maintains apical dominance by repressing:

Axillary buds (C) is correct here. This is core Phytohormone ALL: once you know the definition or pathway step, Axillary buds is the clear fit. The wrong ones are A) Cytokinin; B) Strigolactone; D) Ethylene. If the topic is about gradients or potentials, water/solutes move from higher to lower of the relevant quantity.

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

TIR1, GID1, COI1 and PYL1 are receptors for:

Correct option is A, Auxin, GA, JA, ABA. In Phytohormone ALL problems like this, the accurate statement is Auxin, GA, JA, ABA; the others are common mix-ups. Not these: B) GA, Auxin, CK, ABA; C) Auxin, CK, JA, ABA; D) Auxin, GA, SA, ABA. Tissue transport questions usually turn on xylem vs phloem, living vs dead cells, or source vs sink.

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

COI1 is receptor for:

That points to C: Jasmonic acid. Compared with the other options, Jasmonic acid is the one that correctly describes the Phytohormone ALL concept. The wrong ones are A) Auxin; B) Gibberellin; D) Ethylene. If you’re stuck, eliminate anything that contradicts a basic fact you already know for this topic.

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

JA signaling involves degradation of:

That points to C: JAZ. Compared with the other options, JAZ is the one that correctly describes the Phytohormone ALL concept. The wrong ones are A) AUX/IAA; B) DELLA; D) EBF1. If you’re stuck, eliminate anything that contradicts a basic fact you already know for this topic.

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

Ethylene receptors function as:

Pick B: Negative regulators. Thinking through Phytohormone ALL step by step rules out the lookalikes and leaves Negative regulators. Skip these: A) Positive regulators; C) Transcription factors; D) Ion channels. For hormones and genes, match the molecule or gene to its real role, not a neighboring pathway.

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

Ethylene triple response includes all except:

Go with D — Increased elongation. Under Phytohormone ALL, 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) Reduced elongation; B) Radial swelling; C) Tight apical hook. 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.

SLY1 mutation disrupts ubiquitination of:

Answer: C) DELLA. For Phytohormone ALL, remember the key idea and you’ll land on this option; the distractors usually swap cause and effect or confuse similar terms. Avoid: A) JAZ; B) AUX/IAA; D) EIN3. 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.

GA delays programmed cell death in aleurone by antagonizing:

Pick C: ABA. Thinking through Phytohormone ALL step by step rules out the lookalikes and leaves ABA. Skip these: A) Auxin; B) Cytokinin; D) Ethylene. For hormones and genes, match the molecule or gene to its real role, not a neighboring pathway.

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

GA induces α‑amylase expression in barley in the:

Pick C: Aleurone layer. Thinking through Phytohormone ALL step by step rules out the lookalikes and leaves Aleurone layer. Skip these: A) Embryo; B) Endosperm; D) Coleoptile. For hormones and genes, match the molecule or gene to its real role, not a neighboring pathway.

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

Semi‑dwarf rice gene Sd‑1 affects synthesis of:

That points to B: Gibberellin. Compared with the other options, Gibberellin is the one that correctly describes the Phytohormone ALL concept. The wrong ones are A) Auxin; C) Cytokinin; D) ABA. If you’re stuck, eliminate anything that contradicts a basic fact you already know for this topic.

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

Auxin signal transduction involves degradation of:

Go with C — AUX/IAA proteins. Under Phytohormone ALL, 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) ARFs; B) DELLAs; D) JAZ proteins. 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.