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ABC MODEL+PYQS

Latest questions in this category.

30 questions

SEPALLATA genes belong to which class in ABCDE model?

Correct option is D, E. In ABC MODEL problems like this, the accurate statement is E; the others are common mix-ups. Not these: A) A; B) B; C) D. 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.

Floral quartet model involves formation of:

C fits best: Tetramers. Keep the ABC MODEL basics straight and Tetramers stands out as the precise answer. Avoid: A) Dimers; B) Trimers; D) Pentamers. Light and flowering items often hinge on which photoreceptor or day-length rule is in play.

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

AP2 gene transcripts are detected in:

The right choice is C: All four whorls. In ABC MODEL, that matches how the process or concept actually works — the other choices mix up related ideas or use the wrong mechanism. Skip these: A) Only outer whorl; B) Only inner whorl; D) Only sepals. A quick check: if an option needs energy, pumps, or the opposite direction of movement, ask whether that really applies.

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

AP3/PI mutants show replacement of petals and stamens by:

Go with A — Sepals and carpels. Under ABC MODEL, 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: B) Carpels only; C) Sepals only; D) Petals only. 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.

Which whorls are affected in agamous (AG) mutants?

That points to C: Stamens and carpels. Compared with the other options, Stamens and carpels is the one that correctly describes the ABC MODEL concept. The wrong ones are A) Sepals and petals; B) Petals and stamens; D) Sepals and carpels. 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.

If all five homeotic genes are mutated, flower develops into:

Leaf-like structures (C) is correct here. This is core ABC MODEL: once you know the definition or pathway step, Leaf-like structures is the clear fit. The wrong ones are A) Extra petals; B) Stamens only; D) Inflorescence. 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.

Trithorax proteins function opposite to Polycomb by:

C fits best: Activating floral genes. Keep the ABC MODEL basics straight and Activating floral genes stands out as the precise answer. Avoid: A) Repressing flowering; B) Silencing chromatin; D) Degrading DNA. Light and flowering items often hinge on which photoreceptor or day-length rule is in play.

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

Polycomb proteins regulate flowering by:

The right choice is B: Repressing floral genes. In ABC MODEL, that matches how the process or concept actually works — the other choices mix up related ideas or use the wrong mechanism. Skip these: A) Activating MADS-box genes; C) Degrading transcription factors; D) Transporting hormones. A quick check: if an option needs energy, pumps, or the opposite direction of movement, ask whether that really applies.

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

Cadastral genes mainly function to:

C fits best: Set boundaries of gene expression. Keep the ABC MODEL basics straight and Set boundaries of gene expression stands out as the precise answer. Avoid: A) Specify organ type; B) Induce flowering; D) Repress meristem. Light and flowering items often hinge on which photoreceptor or day-length rule is in play.

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

Loss of function of LFY gene results in:

Correct option is B, Inflorescence instead of flowers. In ABC MODEL problems like this, the accurate statement is Inflorescence instead of flowers; the others are common mix-ups. Not these: A) Extra petals; C) Only carpels; D) Normal flowers. 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.

Which gene is Arabidopsis homolog of Antirrhinum FLO gene?

LFY (B) is correct here. This is core ABC MODEL: once you know the definition or pathway step, LFY is the clear fit. The wrong ones are A) AP1; C) AG; D) PI. 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.