What is the function of digestive enzymes sexreted by cells lining small intestine?

Digestive enzymes secreted by cells lining the small intestine play a vital role in the process of digestion and absorption of nutrients from food. These enzymes help break down complex food molecules into simpler substances that can be easily absorbed by the body. Here are the main functions of digestive enzymes in the small intestine:

1. Carbohydrate Digestion:

- Amylase: Breaks down carbohydrates, such as starch into simpler sugars like maltose and dextrin.

2. Protein Digestion:

- Pepsin: Initiates protein digestion in the stomach and continues to work in the small intestine.

- Trypsin: Breaks down proteins into smaller peptides and amino acids.

- Chymotrypsin: Similar to trypsin, it breaks down proteins into peptides.

- Elastase: Specialized in digesting elastin, a protein found in connective tissues.

- Carboxypeptidase: Removes amino acids from the carboxyl end of the peptide chains.

3. Lipid (Fat) Digestion:

- Lipase: Breaks down triglycerides (fats) into fatty acids and glycerol.

- Phospholipases: Degrades phospholipids, a type of fat found in cell membranes, into fatty acids and other components.

4. Nucleotide Digestion:

- Nucleases: Break down nucleic acids (RNA and DNA) from nucleic acids into nucleotides and nucleosides.

5. Disaccharidases:

- Lactase: Digests lactose, the sugar found in milk and milk products, into glucose and galactose.

- Sucrase: Breaks down sucrose (table sugar) into glucose and fructose.

- Maltase: Converts maltose (from starch digestion) into glucose.

6. Peptidases:

- Dipeptidases and Tripeptidases: Break down small peptides (dipeptides and tripeptides) into individual amino acids.

These digestive enzymes are produced by various cells in the small intestine, including the epithelial cells lining the intestinal villi and crypts, as well as specialized cells called goblet cells and Paneth cells. The enzymes are secreted into the intestinal lumen, where they come into contact with food particles and initiate the chemical breakdown of nutrients.

The proper functioning of these digestive enzymes is essential for efficient nutrient absorption and overall digestion. Any deficiencies or dysfunctions in enzyme production can lead to malabsorption and various digestive disorders.