Digestive System and Food Digestion

Digestion and Nutrition

• Digestion of food begins in the mouth, where the ptyalin enzyme in saliva breaks down carbohydrates into simpler sugars.
• Babies typically have 20 milk teeth, which start erupting when they are around 6-12 months old and are replaced by permanent teeth between 6-12 years old.

Salivary Glands

• There are three pairs of salivary glands in a human being: parotid, sublingual, and submandibular glands.
• Saliva secreted by these glands contains enzymes that break down carbohydrates, facilitating digestion.

Stomach

• The stomach is responsible for the temporary storage of food and the digestion of proteins.
• The stomach lining secretes gastric enzymes, including pepsin and gastric amylase, to break down proteins and carbohydrates.
• Gastritis, an inflammation of the stomach lining, can be caused by bacteria, viruses, or excessive consumption of alcohol or spicy food.

Small Intestine

• The small intestine is primarily responsible for the digestion of carbohydrates, proteins, and fats.
• The inner walls of the small intestine are lined with finger-like projections called villi, which increase the surface area for absorption of nutrients.
• The small intestine is divided into three sections: duodenum, jejunum, and ileum.

Absorption

• The absorption of water, certain medicines, and alcohol takes place in the large intestine.
• The liver secretes bile into the small intestine to help absorb fat.

Large Intestine

• The main function of the large intestine is to absorb water, electrolytes, and vitamins produced by enteric bacteria.
• The large intestine is also responsible for storing and eliminating waste.

Explore the process of food digestion and the organs involved in the digestive system. Learn about the role of the mouth, esophagus, stomach, intestines, and supportive organs such as the salivary glands, liver, gallbladder, and pancreas.