Knowledge Tree
stomata
Facts (13)
Sources
The Ecology of Photosynthetic Pathways | Learn Science at Scitable nature.com 7 facts
claimCAM photosynthetic plants have higher transpiration efficiencies than C3 or C4 plants because they open their stomata at night when vapor pressure differences between the leaf and surrounding air are lowest.
claimTranspiration efficiency is a function of the CO2 concentration gradient (Ca - Ci), where ambient CO2 concentrations (Ca) are relatively constant, but intercellular CO2 concentration (Ci) is determined by the balance between CO2 supply through the stomata and CO2 uptake by photosynthesis.
procedureThe CAM photosynthetic pathway proceeds as follows: (1) stomata open at night to allow carbon dioxide to diffuse into the leaf, (2) carbon dioxide is combined with PEP to form malate, (3) malate is stored in large central vacuoles until daytime, (4) during the day, malate is released from the vacuoles and decarboxylated, and (5) rubisco combines the released carbon dioxide with RuBP in the C3 pathway.
claimMany CAM plants exhibit plasticity in their photosynthetic expression, allowing them to function in a C3 mode with stomata open during the day when water is available.
claimConductance to carbon dioxide (gCO2) is a composite term representing the rate of diffusion through stomata, the rate of diffusion across intercellular air spaces into chloroplasts, and the rate of enzymatic carbon fixation.
claimPlants can maximize photosynthesis by minimizing the resistance to carbon dioxide diffusion through stomata (having many large, open stomata) or by maximizing the biochemical rate of carbon fixation (having high concentrations of photosynthetic enzymes).
claimWater-storing cacti adapt to prolonged drought by closing their stomata, even at night, allowing them to refix CO2 lost in respiration before it diffuses out of the leaf or stem.
The role of light in regulating plant growth, development and sugar ... frontiersin.org Jan 6, 2025 6 facts
claimIn Arabidopsis thaliana, cryptochromes and phytochromes jointly mediate the regulation of stomata by light signals, and stomatal development is inhibited when mutant plants are irradiated by light of the corresponding wavelengths, which affects water transpiration in the plant.
claimLight from the top and side improves leaf structure and anatomy, photosynthesis, and chlorophyll fluorescence, while side light specifically promotes plant growth, improves chloroplast arrangement, induces a higher density of small stomata, and promotes stomatal opening and photosynthetic efficiency (Yang and Jeong, 2021).
claimGreen light treatment in Cucumis melo seedlings regulates stomata, improves water utilization, increases plant height and fresh weight, and reduces leaf stomatal conductance and reactive oxygen species content, which improves drought tolerance.
claimStomata in plants are related to photoreceptors.
claimPlant growth is strongest at 75% irradiation because this level increases photosynthesis, reduces the accumulation of reactive oxygen species, and maintains stomata and chloroplast structure (Ma et al., 2015).
claimLight intensity directly affects the opening and closing of stomata on plant leaves, thereby regulating plant water consumption through transpiration.