Electron micrographs , back

The mitochondrial complex that carries out ATP synthesis is called ATP synthase or sometimes FjFo-ATPase (for the reverse reaction it catalyzes). ATP synthase was observed in early electron micrographs of submitochondrial particles (prepared by sonication of inner membrane preparations) as round, 8.5-nm-diameter projections or particles on the inner membrane (Figure 21.23). In micrographs of native mitochondria, the projections appear on the matrixfacing surface of the inner membrane. Mild agitation removes the particles from isolated membrane preparations, and the isolated spherical particles catalyze ATP hydrolysis, the reverse reaction of the ATP synthase. Stripped of these particles, the membranes can still carry out electron transfer but cannot synthesize ATP. In one of the first reconstitution experiments with membrane proteins, Efraim Racker showed that adding the particles back to stripped membranes restored electron transfer-dependent ATP synthesis. 

Figure 63 Scanning electron micrographs of the failure surface of the white backing layer of the bad packaging sample. Four layers were clearly visible in the SEM images. They are labeled as follows (1) outer clear polyester layer, (2) middle opaque polyethylene layer,... 

Fig. 2.55 Scanning electron micrographs (SEM) in the back scattered electron (BSE) mode at 100,000x of the ABCR MgH + 5 wt.% n-Ni mixtures ball- S milled powder under 700 kPa hydrogen with varying SSA (see the insets in the pictures)...

Back-scattered scanning electron micrograph showing the gradation of AT distribution within the sample. Direction of infiltration is from right to left. 

Cover image is the chemical and molecular structure of the anticoagulant heparin Back cover illustration electron micrographs of drug distribution... 

Figure 2. SEM Back scatter electron micrograph of a straw ash/sand sample heated at 900 C for 6 hours. Dark areas are pores, middle grey are sand grains and light grey rims are the molten ash. 

The desmosomal junction is a morphological entity that is very distinct from adherence junctions involving classical cadherins [44]. The plasma membrane domains of apposing cells are separated by a 20-30 nm thick layer, which in cross section in electron micrographs reveals a midline structure and electron-dense threads stretching laterally from the midline back to the plasma membrane. The cytoplasmic face of each membrane domain is covered with an electron-dense plaque to which bundles of intermediate filaments attach, rather than the actin filaments present in adherence junctions containing classical cadherins. In most epithelia the intermediate filaments are based on keratins but rarer examples of desmosomal junctions coupled into intermediate filaments of the vimentin or desmin type are known [5]. 

Fig.l shows the back-scattered electron micrographs of the polished cross-section of Cf/SiC-BN composite. It is clear that though the inter-bundle matrix is dense, there are still some pores remaining in the intra-bundle areas. Such pores formed because of hindrance to impregnation of... 

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