Morphology vegetative

The second type of material includes spores, which may or may not produce disease symptoms but which can germinate in the insect gut and give rise to vegetative bacterial cells which in turn may produce, and exoenzymes such as phospholipases (lecithinases) or hyaluronidase. The phospholipases may produce direct toxic symptoms owing to their action on nervous or other phospholipid-containing tissue. Hyaluronidase breaks down hyaluronic acid and produces effects on animal tissue which are morphologically similar to the breakdown of insect gut wall in the presence of microbial insecticide preparations. 

Position 5 in Fig. lb describes the brief explosive development of biomass in an ephemeral species capable of exploiting a productive but temporary habitat. Here again morphological plasticity would be expected to predominate. In the vegetative phase, plasticity in root and shoot morphology will be an integral part of the mechanism of resource capture. 

One form of asymmetric division caused by unfavourable conditions is spoliation, which is a highly coordinated process ultimately producing spores which are resistant to adverse environmental conditions. When conditions are favourable, out-growth to vegetative cells then occurs. Streptomycetes and the blue-green bacteria are exceptions to this relatively simple cellular morphology and each of these types of bacteria shows various forms of cellular differentiation, both biochemical and morphological 7,8). 

Klaveness, D. Coccolithus huxleyi (Lohmann) Kamptner. I. Morphological investigations on the vegetative cell and the process of coccolith formation. Protistologica 8, 335 346 (1972). 

Vegetation has been classified into a number of reaction types (Ernst, 1993). Within the group of plants that react to their environment (reactors), those with visible (or overt) reactions can be distinguished from those with non-visible (or covert) reactions. In the case of geobotany as defined by Ernst (1993), visibility means to the unaided human eye, that is colour, morphology, presence, abundance or absence of species. Cole has pointed out (Cole and Smith, 1984) that is was not until about 1945, when rapid routine methods of analysis for large numbers of samples became available, that biogeochemistry, that is the study of the chemical composition of plants from various habitats, was used for mineral exploration in many parts of the world. 

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