Which feedback response decreases transpiration rate when abscisic acid concentration elevates rapidly in xylem sap?

💡 Explanation

When abscisic acid (ABA) concentration increases, ABA induces signaling pathways causing reduced influx of ions into guard cells driving osmosis weakening turgor pressure around stomata, limiting transpiration. Decreasing guard cell turgor leads to stomatal closure, rather than increased expansion, conductivity, or absorption, which require hormonal signalling and pressure gradients.

• Which photosynthetic bottleneck impacts plant growth as temperature rises?
• Which consequence results when a bird increases airspeed without adjusting wing geometry?
• Which process limits oxygen uptake in fish gills if water flow becomes laminar?
• Which disruption occurs when ecdysone signaling is prematurely activated in Drosophila imaginal discs?
• Which outcome destabilizes aquatic food webs dominated by cyanobacteria?
• Which developmental constraint limits the size of insect imaginal discs within a larva?