Answer:
Irritable bowel gives rise to spasm and cramp like abdominal pain. It will not affect digestion but can give rise to diarrhoea and constipation.
Crown's disease on the other hand is caused by inflammation of the bowel which gets damaged. It mostly affects the small bowel but can appear any where in the gastrointestinal tract. It again gives rise to abdominal pain and diarrhoea, and can affect digestion due to poor absorption from the damaged bowel giving rise to weight loss, nutritional and vitamin deficiencies.