18.2 DIGESTION OF FOODS

Digestion

The process that converts large molecules to smaller ones that can be absorbed by the body.

Catabolism

The breakdown of complex molecules into simpler ones, often accompanied by the release of energy.

Carbohydrates digestion begins in the __________.

Mouth.

Enzymes produced in the ________ gland hydrolyze some of the α-glycosidic bonds in carbohydrates.

Salivary.

What are the products of carbohydrate digestion in the mouth?

Maltose, glucose, dextrins.

Dextrins may contain __________ glucose units.

3-8.

The acidic environment of the stomach stops carbohydrate digestion because of its __________.

Low pH.

In the small intestine, the pH is about __________.

What role do pancreatic enzymes play in carbohydrate digestion?

They hydrolyze remaining dextrins to maltose and glucose.

Monosaccharides are absorbed through the __________ to the bloodstream.

Intestinal wall.

Where are fructose and galactose converted to glucose?

In the liver.

Digestion of fats begins in the __________.

Small intestine.

Bile salts break fat globules into smaller particles called __________.

Micelles.

Digestion of triacylglycerols is __________ in the small intestine.

Hydrolyzed.

Triacylglycerols bind to proteins for transport through the __________ system.

Lymphatic.

Protein digestion starts in the __________.

Stomach.

What activates enzymes like pepsin in the stomach?

Hydrochloric acid (HCl) at pH 2.

What does trypsin and chymotrypsin hydrolyze in the small intestine?

Polypeptides to amino acids.

Amino acids are absorbed through the __________ walls.

Intestinal.

What is the end product of protein digestion?

Amino acids.

Digestion of fats, carbohydrates, and proteins is collectively known as __________.

Macronutrient digestion.

The digestive process is essential for __________ absorption.

Nutrient.

Salivary enzymes beginning carbohydrate digestion include __________.

Amylase.

The digestive enzymes produced in the pancreas include __________ for carbohydrates.

Amylase.

What is the main digestive enzyme for proteins produced in the stomach?

Pepsin.

Acidic pH in the stomach denatures proteins, facilitating __________.

Hydrolysis.

After digestion, nutrients are transported to the __________ for utilization.

Cells.

Hydrolysis is the chemical process of __________ bonds in food molecules.

Breaking down.

Before absorption, lipids are arranged into __________ after digestion.

Micelles.

The primary purpose of digestion is to convert food into __________ molecules.

Absorbable.

The final step of carbohydrate digestion is to absorb __________ into the blood.

Monosaccharides.

The small intestine is crucial for the final stages of digestion because it has an optimal __________ for enzyme activity.

pH.

What substance emulsifies fat globules to aid in fat digestion?

Bile salts.

Fat digestion primarily occurs in the __________.

Small intestine.

During protein digestion, what process converts polypeptides into amino acids?

Hydrolysis.

The digestion of amino acids is completed in the __________.

Small intestine.

What is essential for the proper digestion of fats in the small intestine?

Bile.

After being broken down, amino acids enter the __________ for distribution to the body.

Bloodstream.

What is the role of bile in fat digestion?

To emulsify fats.

Carbohydrates are mainly derived from plant-based foods, including __________ and cereals.

Fruits.

Digestion of foods can be categorized into three main types: carbohydrates, fats, and __________.

Proteins.

What is the first step in the digestion of fats?

Emulsification by bile.

Hydrochloric acid in the stomach helps to create a suitable environment for __________ digestion.

Protein.

The digestive process ultimately transforms food into __________ substances for energy.

Nutrient.