The innermost zone of the cortex, zona reticularis, and the middle zone, zona fasciculata, synthesize and secrete glucocorticoids and adrenal androgens. 

TLS Online TPP Program

#Id: 4998

#Unit 6. System Physiology – Plant

To favoring internode elongation is usually reduced leaf area and reduced branching, but at least in the short run this adaptation to canopy shade seems to work.

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#Id: 4999

#Unit 6. System Physiology – Plant

R:FR ratio and seed germination,

large-seeded species, with ample food reserves to sustain prolonged seedling growth in darkness (e.g., underground), do not require light for germination.

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#Id: 5000

#Unit 6. System Physiology – Plant

In all photoperiodic plants,

In the winter when days are short, [P_R] > [P_FR]

In the summer when days are long, [P_R] < [P_FR]

TLS Online TPP Program

#Id: 5001

#Unit 6. System Physiology – Plant

The critical difference is that,

In short-day (i.e., winter flowering) plant species, P_FR inhibits flowering.

In long-day (i.e., summer-flowering) plant species, P_FR induces flowering.

TLS Online TPP Program

#Id: 5002

#Unit 6. System Physiology – Plant

Circadian rhythm in the diurnal movements of Albizia leaves.

TLS Online TPP Program

#Id: 5004

#Unit 6. System Physiology – Plant

During phytochrome-mediated leaflet closure, the apoplastic pH of the dorsal motor cells (the cells that swell during leaflet closure) decreases, while the apoplastic pH of the ventral motor cells (the cells that shrink during leaflet closure) increases.