The small intestine is a tubular structure within the abdominal cavity that carries the food in continuation with the stomach up to the colon from where the large intestine carries it to the rectum and out of the body via the anus.The main function of this organ is to aid in digestion.he small intestine is a tubular structure within the abdominal cavity that carries the food in continuation with the stomach up to the colon from where the large intestine carries it to the rectum and out of the body via the anus. The main function of this organ is to aid in digestion.
Report Abuse. 1  It depends on what the blood work is being drawn for. 2  Depending on the tests, he may need to fast for 12 hours before having the blood work done. 3  This depends on the lab work.  i have had a known practitioner say 10 hours and yet another known practitioner say 12 hours.
Other Considerations. Fasting for blood glucose tests may last as little as two hours, while most other tests need eight to 12 hours of dietary abstinence. Eat a balanced meal prior to your fasting period and again after your blood sample has been taken. Meet every criteria your doctor gives you, and if you make a mistake and take one of your supplements, let the laboratory technician know as soon as you arrive for your blood test.