In the alcoholic fermentation of glucose by yeast, thiamine pyrophosphate is a coenzyme required by:

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#Question id: 34163

#Biochemistry

Which of the following represents the correct sequential pathway for aldosterone synthesis from cholesterol, based on the enzyme-catalyzed steps?

TLS Online TPP Program

#Question id: 34167

#Biochemistry

I. The adrenal medulla does not regenerate, but when the inner two zones of the cortex are removed, a new ZF and ZR regenerate from glomerular cells attached to the capsule.

II. Immediately after hypophysectomy, the ZF and ZR begin to atrophy, whereas the ZG is unchanged because of the action of angiotensin II on this zone. 

III. The ability to secrete aldosterone and conserve Na+ is normal for some time after hypophysectomy, but in longstanding hypopituitarism, aldosterone deficiency may develop, apparently because of the absence of a pituitary factor that maintains the responsiveness of the zona glomerulosa. 

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#Question id: 37829

#Plant Biotechnology

Assertion (A): Plant tissue culture is possible because even highly mature plant cells can dedifferentiate into meristematic cells.

Reason (R): Mature animal cells cannot change back into a proliferative state once they are fully differentiated.

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#Question id: 37830

#Plant Biotechnology

Assertion (A): Plant tissue culture requires aseptic conditions.

Reason (R): Contamination by microbes can compete with plant tissues for nutrients and inhibit growth.

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#Question id: 37831

#Plant Biotechnology

Assertion (A): In plant tissue culture, only tissues with an intact membrane system and viable nucleus can regenerate into a whole plant.

Reason (R): The presence of chloroplasts is essential for dedifferentiation and regeneration.

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#Question id: 37832

#Plant Biotechnology

What is cellular totipotency in plants?