Digestion and the Digestive System

Flashcards covering key vocabulary terms related to digestion and the digestive system.

Digestion

The mechanical and chemical breakdown of foods into forms that cell membranes can absorb.

Mechanical Digestion

Breaks down large particles into smaller ones without changing their chemical composition.

Chemical Digestion

Breaks down food particles by changing them into simpler chemicals.

Alimentary Canal

The continuous tube that extends from the mouth to the anus, serving as a food passageway.

Accessory Organs

Organs that assist in digestion by emptying secretions into the alimentary canal but do not pass food through them.

Mucosa

The innermost layer of the alimentary canal, consisting of a mucous membrane.

Submucosa

The layer that nourishes cells and transports absorbed food molecules.

Muscularis

The muscle tissue layer that moves the tube and food materials through mechanical action.

Serosa

The outermost layer of the alimentary canal that reduces friction with serous fluid.

Peristalsis

A series of wave-like muscle contractions that move food through the digestive tract.

Segmentation

Muscle contractions in the small intestine that mix food with digestive juices.

Salivary Amylase

An enzyme in saliva that begins the chemical digestion of carbohydrates.

Gastric Lipase

A fat-splitting enzyme secreted in the stomach.

Chyme

A semi-fluid mass of partly digested food that passes from the stomach to the small intestine.

Villi

Tiny projections of the mucosa in the small intestine that increase surface area for absorption.

Cholecystokinin (CCK)

A hormone that stimulates gallbladder contraction and bile release into the duodenum.

Defecation

The process of eliminating feces from the digestive tract.

What is digestion?

Digestion is the biochemical process of breaking down food into smaller components that can be absorbed by the body.

What are the main stages of digestion?

The main stages of digestion include ingestion, mechanical digestion, chemical digestion, absorption, and elimination.

What happens during ingestion?

Ingestion is the process of taking food into the mouth, where it is initially broken down by chewing.

What is mechanical digestion?

Mechanical digestion involves physical processes that break food into smaller pieces, such as chewing and the churning of the stomach.

What role does saliva play in digestion?

Saliva contains enzymes that begin the chemical breakdown of carbohydrates and lubricates food for easy swallowing.

What is chemical digestion?

Chemical digestion involves enzymes breaking down food into simpler molecules during the digestive process.

Where does most nutrient absorption occur?

Most nutrient absorption occurs in the small intestine due to its large surface area and presence of villi and microvilli.

What is the function of the stomach in digestion?

The stomach chemically digests food using gastric juices, which contain hydrochloric acid and enzymes, and mechanically churns food.

What is the difference between gastric and intestinal digestion?

Gastric digestion occurs in the stomach with acidic conditions, while intestinal digestion occurs in the small intestine with a neutral pH and involves the pancreas and liver.

What is the role of the liver in digestion?

The liver produces bile, which helps emulsify fats for digestion and absorption in the small intestine.

What is the function of the pancreas in digestion?

The pancreas produces digestive enzymes and bicarbonate, which help neutralize stomach acid and break down carbohydrates, proteins, and fats in the small intestine.

What happens in the large intestine during digestion?

In the large intestine, water and electrolytes are absorbed from indigestible food matter, and waste is prepared for elimination