Lower Plant

Fungi any of a group of parasitic lower plants that lack chlorophyll, including molds and mildews. 

An important field of study for power plants is that of the combinedplant [ 1 ]. A broad definition of the combined power plant (Fig. 1.5) is one in which a higher (upper or topping) thermodynamic cycle produces power, but part or all of its heat rejection is used in supplying heat to a lower or bottoming cycle. The upper plant is frequently an open circuit gas turbine while the lower plant is a closed circuit steam turbine together they form a combined cycle gas turbine (CCGT) plant. 

The objective of combining two power plants in this way is to obtain greater work output for a given supply of heat or fuel energy. This is achieved by converting some of the heat rejected by the upper plant into extra work in the lower plant. 

Fig. 7.2. Combined cycle plant with heat loss between bigber and lower plants.

As already noted, microtubules are also the fundamental building blocks of cilia and flagella. Cilia are short, cylindrical, hairlike projections on the surfaces of the cells of many animals and lower plants. The beating motion of cilia functions either to move cells from place to place or to facilitate the movement of extracellular fluid over the cell surface. Flagella are much longer structures found singly or a few at a time on certain cells (such as sperm cells). They pro-... 

Steam or water injection may also be used, and under some circumstances this can reduce NOx emissions without lowering plant efficiency. Such injection seems to operate in two ways. First, it cools the combustion and hence slows its rate (therefore acting in the same manner... 

Lower plants appear to have been virtually ignored in the search for natural insecticides, although Wilcoxon, Hartzell, and Wilcoxon... 

Whereas the biosynthesis of chlorophylls a and b in higher plants has been described in detail, the synthesis and regulation of related substances found in less well-known algal groups and lower plants are largely unknown and will be areas of scientific interest in the future. Different and new types of chlorophylls and related substances have been reported and little is known about their possible biological... 

The groundwork on the toxicity of sulfur to lower plants was laid in this country by McCallan and Wilcoxon, Liming, and Young and Williams. These studies and those of European investigators have been reviewed well by Horsfall (4) and by Frear (2). 

As a result, organic fruit growers have to make maximum use of preventative or indirect plant protection measures, some of which were already described in terms of their effect on fruit quality (e.g. lower planting densities, see sections above). However, there remains an increased risk for pests and diseases causing stress, decreased photosynthetic activity and capacity. Also in certain sensitive cultivars, the application of permitted plant protection products (such as lime sulphur) can result in phytotoxic effects or latent stress in trees (Palmer et al, 2002). The decrease in photosynthetic activity by both pest/disease attack and pesticides may, in turn, result in reduced fruit quality. Both long-term latent and short-term acute side effects of organic plant protection products have not yet been sufficiently investigated. 

Although this manual is concerned with higher plants, some chapters present information relevant to lower plants. In this connection, the position of the fungi has been debated for years. Most taxonomists do not include fungi in the plant kingdom. However, this manual includes some fungal systems since they are involved in wood decay. 

BIOSYNTHESIS OF Cn HYDROCARBONS IN HIGHER AND LOWER PLANTS (PHAEOPHYCEAE)... 

FIGURE 5 Biosynthesis of Cla hydrocarbons in higher and lower plants. The similar pattern of functionalization of dodeca-3,6,9-trienoic acid and 9-HPEPE is shown. 

PM seems to occur in small amounts in the vegetative tissues of all higher and lower plants investigated. It is very abundant in the tomato fruit,60 orange flavedo and albedo,21 the tobacco plant,61 eggplant62 and alfalfa it usually occurs in the commercial fungal pectinase preparations that are manufactured for the clarification of fruit juices.25 In the natural products in which the enzyme is found, the major portion of it is usually strongly adsorbed on the water-insoluble cellular components of the tissue macerates.60 62 68... 

It has been evidenced that auxin and ACC stimulate ethylene production in some lower plants, for example, in the moss Funaria hygrometrica and in the ferns Pteridium aquilinum and Matteuccia struthiopteris Moreover, ethylene synthesis via the ACC-dependent pathway and in the presence of endogenous ACC and its conjugate in marine unicellular Acetabularia algae was reported. Probably during the evolution of land plants, a relatively primitive pathway of ethylene production was replaced by the ACC-dependent synthesis pathway that now predominates. 

Chitin is a polysaccharide structurally and functionally related to cellulose. The structure is derived from that of cellulose by replacing one of the hydroxyl groups on each monosaccharide unit by an acetamido group, —NHCOCH3. Chitin is the structural polysaccharide of lower plants, such as fungi, and of invertebrates, particularly arthropods. It is the second most abundant organic substance on Earth. 

In 1990, Nakamura et al. reported for the first time the complete biosynthetic origin of the whole carbon skeleton of carbazomycin B isolated from lower plants (378). Based on feeding experiments with and C-labeled compounds, followed by measurement of radioactivity and C-NMR spectroscopy, it was shown that L-tryptophan (408) contributes to C-3 and C-4 of the hexasubstituted aromatic ring, in addition to the indole ring, indicating tryptophan as the progenitor of carbazomycin B (261), in contrast to Chakraborty s proposal of 2-methylcarbazole. The indole part of L-tryptophan (408) is formed by incorporation of two carbons from phosphor-ibosyl diphosphate (430), with loss of the anthraniiic acid (397) carboxyl. The... 

There have been reports of alkaloids in bacteria and it is possible that some alkaloids in marine invertebrates are actually made by bacteria that live on the surface of invertebrate (see Walls JT, Blackman AJ, Ritz AD. (1995). Localisation of the amathamide alkaloids in surface bacteria oiAmathia wilsoni Kirkpatrick. Hydwbiologia, 297,163-72). It would appear that the search for alkaloids in microbes has been less extensive than in higher plants. It is reported that alkaloids are much less common in lower plants and gymnosperms than in angiosperms. 

The flavonoids, the derivatives of 1,3-diphenylpropane, are a large group of natural products, which are widespread in higher plants hut also found in some lower plants, including algae. Most flavonoids are yellow compounds, and contrihute to the yellow colour of the flowers and fruits, where they are usually present as glycosides. 

Mercury fulminate has a sweetish metallic taste. When administered orally it is as poisonous as the majority of mercury compounds. Since, however, it is very sparingly soluble in water its toxicity through contact with the skin is insignificant. Nor is it toxic to lower plants, e.g. moulds often form on the moist bags in which mercury fulminate is stored. 

This widespread occurrence of apiose5 has not been substantiated by Beck.248 In lower plants (1 lichen, 3 mosses, 8 ferns, and 5 Gymnosperms), he detected no apiose. Beck also found no apiose in any of the plants representing families tested by Duff and Knight,5 except the Lemnaceae and Zosteraceae. It should be noted that Duff and Knight5 (also, unpublished data of Duff) did not originally find apiose in all species of any one family in which a member contained apiose, except when some species were re-examined more closely. 

Dioecious In the lower plants referring to the individuals having the archegonia and antheridia on separate plants referring also to those seed plants having staminate and pistillate flowers borne on different individuals. 

Leucosin A white refractive food reserve of unknown chemical composition produced by some of the groups of lower plants. 

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