The stomach secretes the enzyme pepsin to aid digestion. Pepsin mainly acts on which nutrient?
- AOption (a)
Proteins
- BOption (b)
Carbohydrates
- COption (c)
Fats
- DOption (d)
Vitamins
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Correct answer
Proteins
Why this answer is correct
The correct answer is Proteins.
Key Points
- Pepsin is a powerful enzyme found in Gastric Juice that initiates the digestion of proteins by breaking them down into smaller units called Peptones and Proteoses.
- It is secreted by the Chief Cells (peptic cells) of the stomach lining in an inactive proenzyme form known as Pepsinogen.
- The activation of Pepsinogen into Pepsin requires an acidic medium, which is provided by Hydrochloric Acid (HCl) secreted by the Oxyntic Cells (parietal cells).
- The stomach maintains a highly acidic pH level (approximately 1.8), which is the optimum environment for Pepsin to function efficiently as an Endopeptidase.
- By hydrolyzing internal peptide bonds, Pepsin transforms long-chain complex Proteins into shorter polypeptide chains, facilitating further digestion in the Small Intestine.
Additional Information
- Carbohydrates:
- Digestion begins in the Buccal Cavity through the action of Salivary Amylase (Ptyalin).
- Final breakdown into simple sugars like Glucose occurs in the small intestine via Pancreatic Amylase and Disaccharidases.
- Fats:
- Requires Emulsification by Bile Salts produced in the Liver and stored in the Gallbladder.
- The enzyme Lipase, primarily from the Pancreas, breaks down fats into Fatty Acids and Glycerol.
- Vitamins:
- These are Micronutrients essential for metabolic functions but do not require enzymatic breakdown for energy.
- They are absorbed directly in the Small Intestine, specifically in the Ileum for Vitamin B12.