Final answer:
The duodenum is the first part of the small intestine, which extends from the stomach, and is primarily responsible for chemical digestion. It measures about
and connects to the jejunum after the pyloric sphincter.
Step-by-step explanation:
The duodenum is the first section of the small intestine, and it plays a crucial role in digestion. It starts at the pyloric sphincter at the end of the stomach, making a C-shaped curve around the head of the pancreas before connecting to the jejunum. The primary function of the duodenum is chemical digestion, where it uses digestive juices from the pancreas, liver and gallbladder, as well as its own gland cells to break down food particles. This content loaded segment has an alkaline environment that neutralizes the acidic chyme from the stomach, allowing enzymes to digest proteins, fats, and carbohydrates effectively.
These digestive processes transform the food into glucose, triglycerides, and amino acids, with some absorption of fatty acids also happening in the duodenum. Even though it is the shortest part of the small intestine, measuring about
in length, the duodenum's complex interplay with various digestive juices makes it a powerhouse for chemical digestion. Therefore, the correct answer to the student's question would be option C), Extending from the stomach to the small intestine.