Biology · Transport
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Which one gives the most valid and recent explanation for stomatal opening?
- A
Starch hydrolysis
- B
Guard cell photosynthesis
- C
Transpiration
- D
Potassium influx and efflux
Modern research shows stomatal opening is driven by ion movements in guard cells. Potassium ions enter guard cells, lowering water potential and causing water uptake. This increases turgor in guard cells, opening the stomata.
While starch hydrolysis provides energy for cellular processes, it is not the primary mechanism for stomatal opening according to recent findings.
Photosynthesis in guard cells does contribute to the process, but it is not the most recent or valid explanation for stomatal opening.
Transpiration involves water movement through plants and affects stomatal function, but does not directly explain the mechanism of opening.
The movement of potassium ions into and out of guard cells is the primary mechanism for regulating stomatal aperture, affecting turgor pressure and causing stomata to open or close.
Tagged under Biology · Transport