The small intestine is the longest part of the alimentary canal because it is responsible for the majority of nutrient absorption. Its extensive coiling increases its surface area, facilitating efficient absorption of nutrients into the bloodstream.

The exit of food from the stomach is regulated by a sphincter muscle, which releases it in small amounts into the small intestine, allowing for controlled digestion and absorption.

Mucus secreted by gastric glands forms a protective layer over the stomach lining, preventing damage from the acidic environment and digestive enzymes present in the stomach.

Hydrochloric acid in the stomach creates an acidic environment that helps to denature proteins, making them more accessible to enzymatic digestion by pepsin.

Thorough mixing of food with digestive juices in the stomach helps break down food particles into smaller molecules, facilitating enzymatic digestion and nutrient absorption. This process enhances the efficiency of digestion and ensures essential nutrients are extracted from the food ...