Virgo is Dual and Earthy Sign
Activity of Intestine perfectly shows the functioning of Virgo sign.
Food travels slowly thorough the large tract of intestine, whose motion is to and fro (little bit up and down) – This dual movement with food in mostly solid state is perfect symbolism of “Dual” and “Earthy” sign. Due to this dual movement Nutrients and residual of food are separated - All nutrients are absorbed by the body and the unwanted material is discarded.
This shows that Virgo is one the most discriminating sign. They can find the most subtle of the differences and on the flip side could be most nit-picky or literally split hair. On the positive side they are the most analytical mind and no detail can miss their eye.
Intestines are the most discriminatory organ of the body and so the Virgo folks are the most Analytical people who can segregate and analyze facts, data, things or just about everything in the most proper way.
Also just as the Intestine shows slow and tedious "To and Fro" motion of food across it, Virgo people can be adept in doing activities like this for example keeping accounts, book keeping, writing essays, editing a book, editing a newspaper etc.
Virgo is symbolized by a Virgin Girl, who carries Fire in one hand and some grains (wheat) in the sitting on a boat atop vast ocean.
This symbolism can explain many of Virgo qualities. A virgin girl who just attained puberty shows the purity however it is also very easy to get distracted fall for all the pleasures. Thus this sign is associated with both purity as well as excessive indulgence.
A small fire lamp and some grains in a small boat atop ocean - signifies the restriction of resources which Virgo often feels. They are the BEST sign to manage and make do with limited supplies, find resourceful means to manage things.