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Some Difficult Cases Chapter 8 Some Difficult Cases A Practical Guide for Evaluation T he previous chapter analyzed and defended organization as the assay or criterion whereby entities are classified into species. In summary, not only is the presence of species-specific organization sufficient grounds for asserting that something is a member of the species, the absence of such organization is also sufficient grounds for the opposite conclusion, namely, that some entity is not a member of the species. This conclusion holds even for the case of humans who, despite being a special case, still have souls that are by nature the forms of bodies. The present chapter will apply this criterion to cases that arise in the context of development or in the laboratory and will thus both validate the criterion of organization and develop the practical guiding principles necessary for judging actual cases. While the details of embryonic development (human or not) are numbingly complex and still poorly understood, the basic mechanisms of development are reasonably well established. Putting the matter simply , DNA contains sequences that “encode” for particular molecules (largely proteins) that have specific functions in the cell. When a DNA 195 196 Some Difficult Cases sequence is “expressed,” it is first transcribed into an RNA strand. The RNA strand either has its own specific cellular function or serves as the “template” or “messenger” (i.e., mRNA) for the production or synthesis of a particular protein.1 Proteins and non-protein-coding RNAs serve as the fundamental elements of actual development. Proteins are the “building blocks” from which the intra- and inter-cellular structures, which constitute the growth of the organism, are constructed, while non-protein-coding RNAs perform a wide range of regulatory functions and aid in production of proteins.2 These DNA-encoded molecules are the instruments (organa) that actually carry out the construction of the embryo and regulate gene expression, both within and across cells. These basic processes of DNA transcription into RNA and subsequent “translation ” of the RNA into protein are common to all living cells, as well as to developing embryos, and are required for all the metabolic processes of life. What sets embryonic development apart from generic cell metabolism is that it follows a temporal sequence, or trajectory, directed toward the production of increasingly complex structures, ultimately culminating in production of the mature body. While Oyama, Robert, Elliot, and a host of others rightly insist that embryonic development is more than simply the actions of the genes, or even the action of the “genes plus” (to use Robert’s phrase),3 it is nevertheless true to say that genes code for proteins and RNA, which are the fundamental elements of development, and the regulation of protein and RNA production is the basic mechanism whereby embryonic development is accomplished, regardless of the source of the factors responsible for that regulation. In Thomistic terms, protein and RNA 1. Often a single mRNA molecule encodes for a range of related proteins, as a result of “RNA splicing.” Splicing is a process whereby different regions of the “pre-messenger RNA” molecule are excised to generate related mRNAs that encode for proteins sharing some sequences , but often having distinct functions. 2. The three major classes of RNA are as follows: transfer RNA (tRNA) and ribosomal RNA (rRNA), which are involved in protein production; and messenger RNA (mRNA), which encodes for protein. In addition, there is a wide variety of “regulatory” RNA molecules that have diverse functions in regulation of gene expression and processing of other types of RNA to their mature form. 3. See Robert, Embryology, Epigenesis, and Evolution. We understand Robert to mean by “genes plus ...” the view that holds the DNA to be the true agent of development, with the extra-DNA structures present within and between cells serving merely as the passive instruments of its agency. Some Difficult Cases 197 regulation is an act of the augmentative power as it guides the development of the organism. Prima facie then, it would seem that any disruption of protein or RNA regulation sufficient to preclude development while not disrupting the basic processes of cell metabolism would be sufficient to preclude the presence of an organism. If all organisms are hallmarked by their organization , as has been argued, then the lack of distinctly human organizational activities would seem to hallmark the lack of a human organizational principle, that is, soul. Perhaps, prior to such a disruption, there was a human organizational principle present, but subsequent to...

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Additional Information

ISBN
9780813230245
Related ISBN
9780813230238
MARC Record
OCLC
1038796894
Pages
301
Launched on MUSE
2018-06-13
Language
English
Open Access
No
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