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Vertebrates collection

The few additions show that were it possible to carry out subsequent small-vertebrate collections in the whole profile, the stratigraphy of this series of horizons would be transformed. [Pg.136]

The versatility of RNA first became clear from observations of the processing of ribosonial RNA in a single-cell eukaryote. In Tetrahymena (a ciliated protozoan), a 414-nucleotide intron is removed from a 6.4-kb precursor to yield the mature 26S rRNA molecule (Figure 29.37). In an elegant series of studies of this splicing reaction, Thomas Cech and his coworkers established that the RNA spliced itself to precisely excise the intron. These remarkable experiments demonstrated that an RNA molecule can splice itself in the absence of protein. Indeed, the RNA alone is catalytic and, under certain conditions, is thus a rihozyme. More than 1500 similar in-trons have since been found in species as widely dispersed as bacteria and eukaryotes, though not in vertebrates. Collectively, they are referred to as group I introns. [Pg.849]

Vitamin A (retinol) and its naturally occurring and synthetic derivatives, collectively referred to as retinoids (chemical structure), exert a wide variety of profound effects in apoptosis, embryogenesis, reproduction, vision, and regulation of inflammation, growth, and differentiation of normal and neoplastic cells in vertebrates. [Pg.1072]

Particulate emissions into the atmosphere from combustion. Depending on installed filtration and scrubbing systems, fine particles (often <45 p,m) may not be collected efficiently by electrostatic precipitators (ESP Paat Traksmaa 2002) and are deposited on foliage or the ground (Ots et al. 2000), or might be inhaled by vertebrates, including humans. [Pg.265]

Vertebrate animals may be preserved dry or in fluid. Traditional systematic species collections may include study skins, skeletons, and fluid-preserved animals or body parts. Study skins are, as the name implies, the skin of the animal with hair and feathers intact. In small animals, the bones are often left in place since it would be too difficult and damaging to remove them. In study skins, the eyes and mouth are usually filled with cotton, and the body is stuffed gently with either cotton or acid-free tissue in order to keep the skin extended to its original size and shape. Large animals, such as whales or elephants, require a great deal of preparation and storage space. Some researchers may keep only those parts that are relevant to their collections, like the skull or extremities. Soft tissue or stomach contents may be frozen or preserved in alcohol. [Pg.159]


See other pages where Vertebrates collection is mentioned: [Pg.42]    [Pg.407]    [Pg.42]    [Pg.407]    [Pg.97]    [Pg.146]    [Pg.74]    [Pg.266]    [Pg.137]    [Pg.143]    [Pg.64]    [Pg.225]    [Pg.38]    [Pg.365]    [Pg.1254]    [Pg.1360]    [Pg.379]    [Pg.207]    [Pg.41]    [Pg.132]    [Pg.277]    [Pg.349]    [Pg.28]    [Pg.184]    [Pg.38]    [Pg.365]    [Pg.1254]    [Pg.1360]    [Pg.43]    [Pg.456]    [Pg.860]    [Pg.18]    [Pg.273]    [Pg.83]    [Pg.62]    [Pg.138]    [Pg.148]    [Pg.406]    [Pg.252]    [Pg.254]    [Pg.121]    [Pg.38]    [Pg.39]    [Pg.41]    [Pg.43]    [Pg.44]    [Pg.45]    [Pg.47]   
See also in sourсe #XX -- [ Pg.38 , Pg.39 , Pg.40 , Pg.41 ]




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