The fine structure of resin secreting cells of the conical resin ducts in stem of Pinus sylvestris Carr.was studied with the help of high pressure freezing and freeze-substitution techniques. An unprecedented modeof r...The fine structure of resin secreting cells of the conical resin ducts in stem of Pinus sylvestris Carr.was studied with the help of high pressure freezing and freeze-substitution techniques. An unprecedented modeof resin elimination was observed. It seems that the hydrolase-contained Golgi vesicles take part in the dissolution of plasmalemma, and a passage is formed, through which resin material may quickly pass outside of theprotoplast. Then, the ruptured plasmalemma was repaired by some vesicles, possibly derived from Golgi bodies.展开更多
To know more about the site of O -· 2 production in thylakoids, the F v/F m ratio was measured in parallel with the oxygen free_radical production detected by electron spin resonance (ESR) using Tiron...To know more about the site of O -· 2 production in thylakoids, the F v/F m ratio was measured in parallel with the oxygen free_radical production detected by electron spin resonance (ESR) using Tiron as a probe in the isolated thylakoids of Scots pine ( Pinus sylvestris L.). As the light intensity was strong enough to induce photoinhibition leading to reduction in the F v/F m ratio, the intensity of the TH · signal representing the superoxide production was enhanced. The TH · signal was also stimulated by 3_(3,4_dichloropheneyl)_1,1_dimethylurea but was suppressed by exogenous scavengers or by 2,6_dichlorophenol indophenol. Therefore, the superoxide production is closely related to photoinhibition in PSⅡ. The novel results may further promote research on the mechanism of photoinhibition and on the structure and function of PSⅡ as well.展开更多
文摘The fine structure of resin secreting cells of the conical resin ducts in stem of Pinus sylvestris Carr.was studied with the help of high pressure freezing and freeze-substitution techniques. An unprecedented modeof resin elimination was observed. It seems that the hydrolase-contained Golgi vesicles take part in the dissolution of plasmalemma, and a passage is formed, through which resin material may quickly pass outside of theprotoplast. Then, the ruptured plasmalemma was repaired by some vesicles, possibly derived from Golgi bodies.
文摘To know more about the site of O -· 2 production in thylakoids, the F v/F m ratio was measured in parallel with the oxygen free_radical production detected by electron spin resonance (ESR) using Tiron as a probe in the isolated thylakoids of Scots pine ( Pinus sylvestris L.). As the light intensity was strong enough to induce photoinhibition leading to reduction in the F v/F m ratio, the intensity of the TH · signal representing the superoxide production was enhanced. The TH · signal was also stimulated by 3_(3,4_dichloropheneyl)_1,1_dimethylurea but was suppressed by exogenous scavengers or by 2,6_dichlorophenol indophenol. Therefore, the superoxide production is closely related to photoinhibition in PSⅡ. The novel results may further promote research on the mechanism of photoinhibition and on the structure and function of PSⅡ as well.
