Small intestine. The small intestine is made up of the duodenum, jejunum, and ileum. Together with the esophagus, large intestine, and the stomach, it forms the gastrointestinal tract. In living humans, the small intestine alone measures about 6 to 7 meters long.After death, this length can increase by up to half.mall intestine. The small intestine is made up of the duodenum, jejunum, and ileum. Together with the esophagus, large intestine, and the stomach, it forms the gastrointestinal tract. In living humans, the small intestine alone measures about 6 to 7 meters long. After death, this length can increase by up to half.
Obsidian: Characteristics and Properties. Obsidian is the result of volcanic lava coming in contact with water. Often the lava pours into a lake or ocean and is cooled quickly. This process produces a glassy texture in the resulting rock.Iron and magnesium give the obsidian a dark green to black color.ften the lava pours into a lake or ocean and is cooled quickly. This process produces a glassy texture in the resulting rock. Iron and magnesium give the obsidian a dark green to black color.
Obsidian is a naturally formed volcanic glass that was an important part of the material culture of the Olmec and Maya since the Pre-Classic. Like other volcanic glasses, obsidian is a lava that has cooled too quickly for the contained minerals to crystallize.he Obsidian found in the Olmec site of San Lorenzo is mainly from El Chayal in the Central Highlands of Guatemala, and Tajumulco in the western Highlands in Guatemala, meanwhile, that from La Venta is from San Mart n Jilotepeque, also in Guatemala, due to this observations, Andrews (1990: 13) states: