The Digestive System

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Questions and Answers

What is the primary function of the alimentary canal?

To remove waste products from the body

To absorb oxygen from the air

To regulate body temperature

To nourish the body (correct)

What is the inner lining of the cheek called?

Gastrointestinal tract

Oral cavity

Buccal mucosa (correct)

Throat lining

What connects the mouth and nose to the esophagus and larynx?

Esophagus

Larynx

Pharynx (correct)

Trachea

How long is the alimentary canal in length during life?

7.62 meters Signup and view all the answers

What is the function of the accessory digestive organs?

To orchestrate the breakdown of food and assimilation of nutrients Signup and view all the answers

What are the organs that make up the alimentary canal?

Mouth, pharynx, esophagus, stomach, small intestine, and anus Signup and view all the answers

What is the last part of the alimentary canal?

Anus Signup and view all the answers

What is the main function of the mouth?

To allow air and nutrients to enter the body and facilitate speaking Signup and view all the answers

What is the pharynx also known as?

Throat Signup and view all the answers

How long is the alimentary canal in length after death?

10.67 meters Signup and view all the answers

What is the primary function of the esophagus?

To carry food and liquid from the mouth to the stomach Signup and view all the answers

What is the function of the fundus in the stomach?

To store food temporarily before it enters the small intestine Signup and view all the answers

What is the purpose of the pylorus in the stomach?

To connect the stomach to the duodenum Signup and view all the answers

What is the primary function of the gallbladder?

Stores, concentrates, and releases bile Signup and view all the answers

What is the main function of the small intestine?

To absorb nutrients from food Signup and view all the answers

What is the function of villi in the small intestine?

To absorb nutrients from food Signup and view all the answers

Which of the following is NOT a digestive enzyme produced by the pancreas?

Pepsin Signup and view all the answers

What is the function of the duodenum in the small intestine?

To receive digestive juices from other organs Signup and view all the answers

What is the primary function of the exocrine gland in the pancreas?

Produces digestive enzymes to aid in digestion Signup and view all the answers

What is the term for the movement of food through the digestive tract?

Propulsion Signup and view all the answers

What is the function of the jejunum in the small intestine?

To mix food with digestive juices Signup and view all the answers

What is the function of the ileum in the small intestine?

To move food waste gradually toward the large intestine Signup and view all the answers

What is the primary function of the liver in digestion?

Produces and exports bile to the duodenum Signup and view all the answers

What is the function of the large intestine?

To reabsorb water and maintain fluid balance Signup and view all the answers

What is the term for the breakdown of food into smaller particles?

Mechanical digestion Signup and view all the answers

What percentage of carbohydrates and protein are absorbed in the small intestine?

95% Signup and view all the answers

What is the term for the entry of food into the alimentary canal?

Ingestion Signup and view all the answers

What is the function of amylase produced by the pancreas?

Breaks down carbohydrates for energy Signup and view all the answers

What is the term for the absorption of nutrients into the bloodstream?

Absorption Signup and view all the answers

What is the term for the release of waste products from the body?

Defecation Signup and view all the answers

Which of the following is NOT a type of digestive disorder?

Diabetes Signup and view all the answers

What is the term for the process of breaking down complex food molecules into their chemical building blocks?

Chemical digestion Signup and view all the answers

Where does the majority of absorption take place?

Small intestine Signup and view all the answers

What is the name of the 'acidic soup' formed in the stomach during digestion?

Chyme Signup and view all the answers

What is the purpose of segmentation in the small intestine?

To mix food with digestive juices Signup and view all the answers

What is the name of the lab test used to detect colon cancer?

Occult blood test Signup and view all the answers

What is the term for the process of removing undigested materials from the body?

Defecation Signup and view all the answers

What is the name of the lab test used to diagnose stomach ulcers?

C- urea breath test Signup and view all the answers

Which of the following is a type of parasitic infection?

Ova and Parasites Signup and view all the answers

What is the primary function of the digestive system?

To break down food into nutrients Signup and view all the answers

Study Notes

Digestive System

The digestive system uses mechanical and chemical activities to break down food into absorbable substances.
The digestive system can be divided into two main categories: organs that make up the alimentary canal and accessory digestive organs.

Alimentary Canal Organs

The alimentary canal, also called the gastrointestinal (GI) tract or gut, is a one-way tube about 7.62 meters (25 feet) in length during life and closer to 10.67 meters (35 feet) in length after death.
The main function of the organs of the alimentary canal is to nourish the body.
The alimentary canal consists of the mouth, pharynx, esophagus, stomach, small and large intestines, and anus.

The Mouth

The mouth is part of the digestive system and is also called the oral cavity.
The inner lining of the cheek is known as the buccal mucosa.

The Pharynx

The pharynx, commonly called the throat, is a muscular, funnel-shaped passageway inside the body.
It connects the mouth and nose to the esophagus (leading to the stomach) and larynx (leading to the trachea and then lungs).

The Esophagus

The esophagus is a hollow, muscular tube that passes food and liquid from the throat to the stomach.
The primary function of the esophagus is to carry food and liquid from the mouth to the stomach.

The Stomach

The stomach is a J-shaped organ that digests food.
It produces enzymes and acids that break down food so it can pass to the small intestine.
There are four main regions in the stomach: the cardia, fundus, body, and pylorus.

The Small Intestine

The small intestine is the longest part of the alimentary canal, about 3.05 meters (10 feet) long.
It is where most digestion occurs and where practically all absorption occurs.
The small intestine is subdivided into three regions: the duodenum, jejunum, and ileum.
Villi in the small intestine are specialized for absorption, having a thin wall, one cell thick, which enables a shorter diffusion path.

Accessory Structures

Accessory digestive organs aid in the breakdown of food.
The liver, pancreas, and gallbladder release secretions essential for digestion.
The gallbladder stores, concentrates, and releases bile.
The pancreas produces pancreatic juice, which contains digestive enzymes and bicarbonate ions.

Liver

The liver is the largest gland in the body, weighing about three pounds in an adult.
It plays important roles in metabolism and regulation.
The digestive role of the liver is to produce bile and export it to the duodenum.

Pancreas

The pancreas is an organ and a gland.
It performs two main functions: exocrine function (produces substances that help with digestion) and endocrine function (sends out hormones that control the amount of sugar in the bloodstream).
The pancreas produces lipase, amylase, and protease enzymes.

Gallbladder

The gallbladder is a small, pear-shaped organ that stores and releases bile.
Bile helps the digestive system break down fats.

Digestive Processes

The processes of digestion include six activities: ingestion, propulsion, mechanical or physical digestion, chemical digestion, absorption, and defecation.
Ingestion refers to the entry of food into the alimentary canal through the mouth.
Propulsion refers to the movement of food through the digestive tract, which includes the voluntary process of swallowing and the involuntary process of peristalsis.
Mechanical digestion is a purely physical process that does not change the chemical nature of the food.
Chemical digestion starts in the mouth, and digestive secretions break down complex food molecules into their chemical building blocks.
Absorption takes place primarily within the small intestine, where food that has been broken down enters the bloodstream, and its nutrients are put to use.
Defecation is the final step in digestion, where undigested materials are removed from the body as feces.

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Description

Learn about the mechanical and chemical activities of the digestive system, and how it breaks down food into absorbable substances.