Standard Anatomical Position
Because animals can change orientation with respect to their environment, and because appendages (arms, legs, tentacles, etc.) can change position with respect to the main body, it is important that positional descriptive terms refer to the organism when it is in its standard anatomical position.
Thus, all descriptions are with respect to the organism in its standard anatomical position, even when the organism in question has appendages in another position. For example, see Fig. 9, where the tentacles are curved, and therefore not in anatomical position. However, a straight position is assumed when describing the proximo-distal axis. This helps avoid confusion in terminology when referring to the same organism in different postures.
Read more about this topic: Anatomical Terms Of Location
Famous quotes containing the words standard and/or position:
“A dwarf who brings a standard along with him to measure his own size—take my word, is a dwarf in more articles than one.”
—Laurence Sterne (1713–1768)
“Men were only made into “men” with great difficulty even in primitive society: the male is not naturally “a man” any more than the woman. He has to be propped up into that position with some ingenuity, and is always likely to collapse.”
—Wyndham Lewis (1882–1957)