Describe the gut and nutrient absorption.

Gut; The portions of the alimentary canal, particularly the stomach and the intestines (sometimes including the anus, especially in animals that eliminate wastes through the anus, in contrast to other animals that excrete waste through the mouth or by other means).

The main role of your small intestine is to absorb nutrients from the food you eat into your bloodstream ... Nutrients that the small intestine often has trouble absorbing can be macronutrients (proteins, carbohydrates, and fats), micronutrients (vitamins and minerals), or both.

Absorption of the majority of nutrients takes place in the jejunum, with the following notable exceptions: Iron is absorbed in the duodenum.