The diagram shows the human digestive system - Edexcel - GCSE Biology - Question 6 - 2017 - Paper 1

The primary product of carbohydrate digestion is glucose, which is the simple sugar that results from the breakdown of starch.

The small intestine has several crucial functions in digestion:

1. Absorption of Nutrients: The small intestine is responsible for absorbing nutrients from digested food into the bloodstream. This process occurs mainly in the duodenum and jejunum, where villi and microvilli increase the surface area for absorption.

2. Digestion of Food Molecules: Enzymes produced by the pancreas and the intestinal lining further digest food molecules, breaking down proteins, fats, and carbohydrates into their simpler forms for absorption.

3. Peristalsis: The small intestine facilitates the movement of food along the digestive tract through a process called peristalsis, which involves rhythmic contractions of the intestinal walls.