i have tryed to source the question you require i belive the answer is here for you heres the URL hope it helped
http://www.eapsa.org/parents/short_bowel.cfm
yes...it may not be super common but everyones body is different. People can have extra and they can have less.
Intestines can get Chrohn's disease, which causes blockage in the intestines and can lead to cancer.
it can cause the small intestines to stretch but i dont know about the large intestines
It is caused by inflammation of stomach and intestines.
Digestive
Yes. Coffee contains a lot of caffeine (depending on brand and brewing method). This causes the intestines to become stimulated, and increased movement of the intestines causes a bowel movement.
A very small antelope which causes constipation and bloating
lipids
The causes of a hereditary disease is a missing chromosome, and extra chromosome. Like in Down Syndrome there is an extra chromosome 26.
it backs up in your intestines and causes weight gain.
Cystic fibrosis
That person is a gastroenterologist.