ABA signaling in guard cells is largely mediated through the second messenger Ca2+.

TLS Online TPP Program

#Id: 3775

#Unit 1. Molecules and their Interaction Relevant to Biology

The electrons revolve in orbits around the nucleus.

TLS Online TPP Program

#Id: 2334

#Unit 3. Fundamental Processes

The E. coli rrn  promoters are also regulated by a pair of small molecules: the initiating NTP (the iNTP) and an alarmone,  guanosine 5 -diphosphate 3-diphosphate (ppGpp). 

1. An abundance of iNTP indicates that the concentration of  nucleotides is high, and therefore it is appropriate to synthesize plenty of rRNA. 

2. Accordingly, iNTP stabilizes the open promoter complex, stimulating transcription. 

3. On the other hand, when cells are starved for amino acids, protein synthesis cannot occur readily and the need for ribosomes (and rRNA) decreases. 

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#Id: 7300

#Unit 6. System Physiology – Plant

Crassulacean acid metabolism (CAM). Temporal separation of CO2 uptake from photosynthetic reactions: CO2 uptake and fixation take place at night, and decarboxylation and refixation of the internally released CO2 occur during the day. The adaptive advantage of CAM is the reduction of water loss by transpiration, achieved by the stomatal opening during the night.

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#Id: 909

#Unit 13. Methods in Biology

Tetrazolium compound MTT (3-(4,5-Dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide MTT Assay is calorimetric assay to detect cell division

TLS Online TPP Program

#Id: 10156

#Unit 6. System Physiology – Plant

Strigolactones as signal that interact with auxin in regulating apical dominance