Human Anatomy, Part 1 - K. A. Dyubenko, A. K. Kolomiytsev, Yu. B. Chaykovsky 2002

Special Part
Splanchnology, splanchnologia [the study of viscera] — Digestive system, systema digestorium
Intestine — Large intestine

The Large Intestine, intestinum crassum, is a continuation of the digestive tract. It frames the Small Intestine like an arch and terminates in the pelvic region at the anus (Fig. 236). The large intestine absorbs Water, and forms and excretes feces. The Glands of the mucous membrane in the large intestine produce mucus, which binds together undigested food residue and facilitates its passage through the segments of the large intestine. The absorptive capacity of the large intestine is utilized in clinical practice to administer medications and nutrients to patients via enemas, per rectum.

The large intestine is divided into six sections:

- cecum, caecum;

- descending colon, colon descendens;

- ascending colon, colon ascendens;

- sigmoid colon, colon sigmoideum;

- transverse colon, colon transversum;

- rectum, rectum.

The length of the large intestine ranges from 1.5 to 2 m, and its diameter varies from 4 to 8 cm across different segments. Externally, the large intestine differs from the small intestine by the presence of: colic taeniae (teniae coli), haustra, and omental (epiploic) appendages (see Fig. 236).

Class="center">

Fig. 236. The large intestine, intestinum crassum (diagram)

The colic taeniae, taeniae coli, are formed due to the uneven distribution of longitudinal Muscle bundles along the course of the large intestine. Their width reaches up to 1 cm. They include: the omental (epiploic) taenia, taenia omentalis; the mesenteric taenia, taenia mesocolica; and the free taenia, taenia libera, of the colon. The colic taeniae serve as a landmark for surgeons during operations for inflammation of the vermiform Appendix, appendicitis.

The haustra of the colon, haustrae coli, are formed because the taeniae are shorter than the other layers of the intestinal wall, thus gathering the wall into sacculations, or haustra.

Omental (epiploic) appendages, Appendices epiploicae, are peritoneal outgrowths 3–5 cm in length, located along the course of the omental and free taeniae.