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Re: Mice given bat-like forelimbs through gene switch



One could argue that viruses are single celled (the
part they are missing that constitutes life is a
metabolism, not a coating)

Most don't have a cell membrane, though. The only thing they have in common with a cell is the presence of DNA and/or RNA and of proteins.


----------------

I checked the links for context...

From: Principles of Anatomy and Physiology

http://books.google.com/books?id=qGp3HQe2B_4C&dq=tissue+level+organization&q=organism&pgis=1#search

"Cells are the basic structural and functional units
of the organism."

Does not preclude an organism from consisting of one such unit.

From: Modern Biology

http://books.google.com/books?id=E_ooNitL-pkC&pg=PT334&dq=tissue+level+organisation&lr=&sig=2VG2cteryNt1tay-HLW5y4Cw_rQ#PPT50,M1

"6. Organism level

In an organism various organ systems are integrated to
perform the life activities. A complex multicellular
organism, such as human being [sic], represents an
extremely high level of organisation."

That's more like it, but it doesn't seem to take anything unicellular into account, and, as mentioned, it says "multicellular organism" as if that weren't saying the same thing twice.


From: Plant Biomechanics: An Engineering Approach to
Plant Form & Function.

http://books.google.com/books?id=l3bRJVMbNMcC&printsec=frontcover&dq=plant+biomechanics&lr=&sig=7Thj07MFyWBdGedcSFWhNLdPJHY#PPA34,M1

Has a lot of context about cell theory vs organismal theory (...which strike me not so much as scientific theories as as ways of looking at the matter philosophically... indeed, the chapter is called "Some Biological and Philosophical Preliminaries"); in the former, organisms consist of at least one cell, in the latter, organisms are completely or incompletely or not at all divided into cells. Thus, in the former, organisms can be single-celled; in the latter, it can't, but that's because the concept of "cell", not the concept of "organism", doesn't make sense in that case!


Quote from p. 35: "The organismal theory essentially views the organism as a continuous mass of protoplasm (the symplast) that may or may not be incompletely partitioned into cells during the plant's [!!!] ontogeny. Plant and animal [!] cells are viewed as the result of ontogeny, not as its cause, and unicellular and multicellular organisms are placed in parity with one another -- the latter is the septated equivalent of the former."

Here we have a mention of "unicellular [...] organisms."

Then the text continues, including another mention of how an "organism" can be a "unicellular individual":

"The differences between the cell and organismal theories, summarized in table 1.2, are fundamental to our views on development, morphogenesis, evolution, and biomechanics. Multicellularity must be viewed as a highly specialized expression of development in which the division of the protoplasm and the division of the nucleus are highly correlated. When the protoplasm partitions itself differently from the way nuclei divide, the organism may become a multinucleated but unicellular individual (e.g., *Caulerpa*; see fig. 1.6A). From this starting point we can explore the notion of multicellularity as it pertains to plant biomechanics."

Table 1.2 (on p. 34) mentions "unicellular organisms" several times.

Incidentally, the mentioned context contains the embarrassing translation of "Om[n]is [sic!] cellula e cellula" as "All is cells and cells". This is wrong for something like five reasons at once; in reality, the quote means "every cell [has come] out of [a] cell", i.e., cells aren't built from outside, they reproduce. It doesn't even imply that all living beings consist of cells! The grammar of the translation of the German quote later on the same page is a bit off, too (singular translated as plural, plural also translated as plural), but at least it doesn't miss the point, let alone so completely!

From: Biology: A Functional Approach.

http://books.google.com/books?id=OT-O2DJXrMwC&pg=PP1&dq=biology+a+functional+approach&lr=&sig=SSiAOSc-est4KXgJctfKZL43F9A#PPA14,M1

"The cell theory states that the cell is the basic
unit of an organism, the whole organism being little
more than a collection of independent cells; the
organismal theory states that the whole organism is
the basic unit, the cells being incidental sub-units."

Later on the same page (point 6), "unicellular organisms" occurs: "Some animal cells and unicellular organisms possess _cilia_ or _flagella_."


Does any of this help clear things up?

Oh yes, it clears up your misunderstanding! :-) Or maybe that of your professors.


It's still an oxymoron.

(Why is "oxymoron" so popular in English as a word for "contradiction in terms"? It's supposed to mean "sharp stupidity", "something that looks stupid but actually contains deep wisdom" as a literary device.)


This is somewhat similar to the issue of calling all
insects and arachnids: bugs.

I don't see how.