Reproductive mechanism

Viruses don t have a reproductive system of their own and need to take over healthy cells by puncturing them with tiny spikes called hemagglutinin so that they can use the cells reproductive mechanism to make more viruses. These viral spikes are coated with an enzyme called neuraminidase, which helps to break down cellular walls. Flavonoids that occur in elderberries inhibit viral action and thereby improve immune response. It is thought that the flavoniods may also inhibit the action of neuraminidase. 

Also, if the self-replicating structure were to possess chemical information, and in addition the capability to mutate, then self-reproduction, information and evolution would occur all at the same time something already very close to life (see Figure 7.1). It is then clear why the search for self-reproduction mechanisms is the holy grail of the research on the origin of life. 

The reproduction mechanism of Q(3, an RNA virus capable of infecting bacteria, is shown schematically in Fig. 1. During the replication of RNA,... 

Bauld, J. and Tyler, P.A., 1971. Taxonomic implications of reproductive mechanisms of Hyphomicrobium-iacies and Pedomicrobium-iacies of a pleomorphic budding bacterium. Antonie van Leeuwenhoek J. Microbiol. Serol., 37 417—424. 

The pulverised selected biomass which contains the stabilized electron- and the proton-donors generates hydrogen when solar beam irradiates onto it. This Reproduction mechanism is very similar to photosemiconductor- and photo-catalysis- methods. 

The self-reproduction mechanism illustrated here for vesicles is of course extremely primitive with respect to the self-replication mechanisms of RNA. However, one should recognize that the first prebiotic self-replicators cannot have been chemically well-developed and sophisticated macromolecules. Most likely, the first replicators were primitive structures. In this sense, the self-reproducing supra-molecular structures have a distinct relevance, since the reproduction mechanism happens almost spontaneously. 

Of the organelles which can be separated by the fractionation techniques, the largest and heaviest are the nuclei. They are found in all animal and plant cells (with the exception of the red blood corpuscles of some mammals) and are intimately concerned with the reproductive mechanisms of the cell. They contain virtually all the cell DNA, a fair amount ofRNA, and considerable amounts of basic proteins (histones, see page 68) that we have already referred to as being associated with DMA. The complex of DNA/ RNA/protein is called chromatin and at certain stages in the... 

The voodoo lily is a beautiful and seductive plant. The exotic-looking lily features an elaborate reproductive mechanism—a purple spike that can reach nearly 3 feet in length and is cloaked by a hoodlike leaf. But approach to the plant reveals bad news—it smells terrible ... 

Natural selection will work effectively only when a sufficient variety of organisms exists within a population. This variety of organisms is called genetic variation, and nature has several reproduction mechanisms that contribute to this variation. They include mutation, genetic recombination, and bringing in genetic material from a different population. All these mechanisms operate on the level of genotypes and allies. 

To a large extent, the formal kinetic analysis techniques presented in this chapter relate to discontinuous batch operations. Even if the goal is a continuous operation, the batch process kinetic model serves as a start-up. The most significant element of a kinetic analysis is the time dependence of the macroscopic process variables mentioned in Chap. 2. Bacteria, molds, viruses, and yeasts all have different reproduction mechanisms, and formulating a structured kinetic model more closely related to the actual mechanism is a desirable goal. More structured models are desirable not only to deal with active cells but also to extend kinetic analysis to more complex situations involving inactive cells, mixed populations of cells, multiple substrates, and... 

Evidence of activities of alkaloids in the DNA reproduction mechanism is impressive. Some alkaloids are used as drugs for inhibiting the development, e.g., of animal cancerous tumors, including humans (Kup-chan and By, 1968 Kupchan, 1975), some are known for hallucinogenic properties (Schultes, 1975 Wall, 1975 Hoffman et al., 1975), antimicrobial effects (Mitscher, 1975), neurotoxins (Kessler, 1975), and teratogenic (Kuc, 1975) and allergenic behavior (Mitchell, 1975), and some are used in folk medicine (Duke, 1975). 

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