Biological Molecules Breakdown

Introduction

• Biological molecules in our diet consist of carbohydrates, proteins, and lipids.
• These molecules need to be broken down by enzymes into smaller, soluble molecules for absorption.
• Large molecules can't be absorbed across the villi of the small intestine until broken down.

Role of Enzymes

• Enzymes are specialized proteins that accelerate chemical reactions.
• Each type of food molecule is broken down by specific enzymes.

Breakdown of Carbohydrates

• Carbohydrates Sources: Foods like pasta and potatoes.
• Structure: Mainly in the form of starch, a polymer of glucose (monomers).
• Enzymes:
  • Amylase: Breaks starch into maltose (two glucose molecules).
  • Maltase: Breaks maltose into glucose, ready for absorption.
• Enzyme Naming: Many enzyme names end with "-ase".

Breakdown of Proteins

• Protein Sources: Foods like meat and nuts.
• Enzymes: Protease enzymes break proteins into amino acids.
  • Proteases include specific enzymes such as trypsin and pepsin.
• Amino Acids: Different types, but specific differences are not required knowledge.

Breakdown of Lipids

• Lipids Sources: Fats and oils from foods like avocados and olive oil.
• Enzymes: Lipase enzymes break lipids into glycerol and fatty acids.
• Role of Bile:
  • Not an enzyme, but aids lipid breakdown by emulsifying them.
  • Emulsification increases the surface area for lipase action.

Enzyme Production Sites

• Pancreas and Small Intestine: Produce all three types of enzymes (amylase, protease, lipase).
• Salivary Glands: Produce amylase for initial carbohydrate digestion.
• Stomach: Produces protease enzymes.

Additional Resources

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