DIGESTIVE FINALS ANAPHY

Digestive System

This performs the vital task of transforming the food into chemicals that can be absorbed into cells and be used as energy by the body.

Mouth

Pharynx 

Esophagus

Stomach

Small intestine

Large intestine

Anus

What are the Digestive (Alimentary) Tract?

Teeth

Tongue

Salivary glands

Liver

Pancreas

Gallbladder

What are the Accessory Organs?

Gastroenterology

The study of the digestive tract and the diagnosis and treatment of its diseases.

Ingestion

Occurs in the mouth (oral cavity); the intake of solid or liquid food into the digestive tract.

Mastication

Process by which the teeth chew food in the mouth.

Propulsion

Movement of food from one end of the digestive tract to another, which takes approximately 24-36 hours.

Swallowing, Peristalsis, Mass movement

What are the three processes of Propulsion?

Swallowing

Also means deglutition, moves the food (bolus) from the oral cavity to the esophagus.

Peristalsis

Propels material through most the digestive tract.

Mass movement

Contractions that move materials in some parts of the large intestine.

Mixing

Moves forward and backward in order to break down food into smaller pieces.

Secretion

Added to lubricate, liquify, buffer, and digestion the food.

Digestion

Breakdown of large organic molecules into smaller component parts.

Break down food and transform it into a substance that the cells can use.

Glycogens

Carbohydrates break down from?

Monosaccharides

Starch break down into?

Absorption

Movement of molecules out of the digestive tract and into the circulation or the lymphatic system.

Elimination

Process by which the waste products of digestion are removed from the body.

Mucosa, Submucosa, Muscularis

What are the tissue layers of Digestive Tract?

Mucosa

Innermost layer of the Digestive Tract and Stomach

Mucous epithelium

Lamina Propria

Muscularis mucosae

What are the three layers of Mucosa?

Mucous epithelium

It is the inner layer of epithelial tissue in the Mucosa

Lamina propria

It is the loose connective tissue in the Mucosa

Muscularis mucosae

It is the thin layer of smooth muscle in the Mucosa

Submucosa

Thicker layer of connective tissue of the Digestive tract and Stomach. Contains glands, blood vessels, lymphatic vessels, and nerves.

Muscularis

Regularly contracts and relaxes to propel food in the Digestive tract.

Circular and Longitudinal muscle layer

What are the 2 layers of smooth muscle in the Muscularis?

Serosa

Outermost layer, also known as the visceral peritoneum. Covers the portion of the digestive tract within the peritoneal cavity.

Peritoneal Cavity

Organs within the digestive system are suspended. This suspension allows the digestive organs to move and perform functions.

Mesentary

A layer of visceral peritoneum that suspends the digestive organs within the abdominopelvic cavity, while anchoring them closely to the abdominal wall.

Contains blood vessels, nerves, lymphatic vessels, and lymph nodes, which supply the digestive tract.

Peritoneal Fluid

Lubricating fluid that fills the hollow spaces in the peritoneal cavity. Under normal conditions, only a small amount of it is present. However, the volume of it can increase abnormally during injuries.

Ascites

Is the abnormal increase of peritoneal fluid, usually occurs when there is trauma or disease in the peritoneal cavity.

Mouth

The oral or buccal cavity; the entryway to the digestive tract and where the digestive tract begins.

Surrounded by the lips and borders on each side, the cheeks.

Lips

The door of the oral cavity.

Orbicularis oris muscle and connective tissue

What are the 2 muscle structures formed in the Lips?

Tongue

A skeletal muscle covered by mucus membrane that forms the floor of the mouth.

Used to reposition food in the mouth during mastication

Lingual papillae

What are the taste buds within the projections called in the tongue?

Hard Palate

Formed by portions of the maxillae and palatine bones; separates the mouth from the nasal cavity.

Soft Palate

Consists of mostly skeletal muscle. Forms an arch between the mouth and

nasopharynx.

Lingual Frenulum

A fold mucous membrane that anchors the tongue to the floor of the mouth.

Contains superficial blood vessels that populate the floor of the mouth.

Ideal site for soluble drugs to be absorbed quickly into the circulation.

Uvula

Cone-shaped process; hangs downward from the soft palate.

Aids with speech as it blocks air going through the nasal pathway.

Teeth

Break down food into small pieces, enough for it to be swallowed.

Saliva

Aids in food breakdown.

Deciduous teeth

What do you call the 20 temporary teeth which begin to erupt at the age of 6 months?

8-12 months

When do the deciduous teeth become fully visble?

6-13 years old

What age do deciduous teeth fall out and are replaced with permanent teeth?

32 permanent teeth

How many permanent teeth does the adult mouth contain designed to cut, tear, and

grind food?

Maxillary and Mandibular arch

What are the two dental arches?

Incisors

Have sharp edges for cutting food

Canine teeth

Designed to tear food; called the cuspid teeth during primary stage

Premolars and Molars

Have large, flat surfaces for crushing or grinding food

Wisdom teeth

What are the 3rd molars called and is impacted or grows sideways which needs to be surgically removed?

Crown

Visible portion; located above the gums, or gingiva.

Neck

Connects the crown to the root.

Root

Below the gums, embedded in a socket in the jaw bone.

Enamel

Hard tissue that covers the crown; hardest substance in the body because it is made of pure minerals. It cannot regenerate when damage occurs.

Dentin

Yellowish tissue between enamel and pulp; when damage occurs, this can regenerate.

Pulp cavity

Contains connective tissue, blood and lymphatic vessels, and nerves. When damage occurs, it is usally painful as it contains nerve endings.

Periodontal ligament

Lines the socket which anchors the tooth into the mandible.

Cementum

Covers the dentin at the root; when damage occurs, this can regenerate.

Salivary Glands

Secretes 1 liter of saliva a day.

Secrete the enzyme amylase.

Saliva

A clear fluid, consisting of water, mucus, enzymes, anti-bacterial compost, and electrolytes. Moistens the mouth, and lubricates and protects the teeth; moisten food and transform it into a mass called bolus.

It also contributes to the detection of taste

Salivary amylase and Lingual Lipase

What are the two enzymes contain in the saliva?

Salivary Amylase

It breaks down the starch

Lingual Lipase

Begins the digestion of fat

Stimulation

The taste, smell, sight, or thought of food.

Prevention

The stimulation of the sympathetic nervous system.

Parotid gland

A type of gland that lie just underneath the skin anterior to the ear; target of mumps virus, or beke.

Submandibular gland

A type of gland that empties into the mouth on either side of the lingual frenulum; located below the mandible.

Sublingual gland

A type of gland that drains through multiple ducts onto the floor of the mouth

Serous Saliva

Moistens the food and mucus membrane; neutralizes bacterial acids.

Salivary Amylase

Digest carbohydrates.

Hydrolyze polysaccharides into disaccharides.

Mucus

Lubricates food; protects digestive tract from digestion by enzymes.

The secretion of the esophagus, lubricates and protects the lining of the esophagus against abrasion, and allows the smooth transition of food to the stomach.

Protects stomach lining from digestion; lubricates and protects the epithelial cells in the stomach wall.

Protection of duodenum from gastric acids and intestinal enzymes; provides adhesion for fecal matter; protects intestinal walls from bacterial action and acid produced from the feces.

Lingual Lipase

Digest a minor amount of lipids.

Nasopharynx, Oropharynx, Laryngopharynx

What are the three parts of the Pharynx?

Oropharynx and Laryngopharynx

These are the two types of Pharynx that transmit food.

Voluntary, Pharyngeal, and Esophageal

What are the three phases of Deglutition?

Voluntary

It is the swallowing

Pharyngeal

Food goes through Pharynx

Esophageal

Food goes through the esophagus

Chew food → becomes bolus → goes to pharynx after we swallow voluntary → the soft palate lifts and blocks the nasal cavity → food moves through oropharynx and laryngopharynx → esophagus

What is the swallowing process?

22 muscles

Swallowing requires the coordination of how many muscles?

Medulla oblongata and pons

Where do the nerve impulses occur to control the 22 muscles?

Upper Esophageal Sphincter

Blocks food so it doesn’t go in the trachea.

Esophagus

Connects the pharynx to the stomach; about 10 inches (25 cm) long.

Lies posteriorly to the trachea and travels through the mediastinum, penetrates the diaphragm, and enters the stomach.

Mucosa

Submucosa

Mascularis

Adventitia

What are the four layers of the Esophagus?

Lower Esophageal Sphincter

A muscular sphincter that helps prevent the backflow of stomach acid into the esophagus.

Prevents heartburn, a burning sensation resulting from the regurgitation of acidic stomach contents into the esophagus.

Stomach

Its primary function is to store food; prepares food for digestion (most chemical digestion occurs in the intestines)

Low pH of stomach acid inactivates the salivary amylase; no chemical digestion occurs.

Contains the enzyme, pepsin which hydrolyzes the peptide bonds between certain amino acids.

Contains gastric lipase

Chyme

Semi-fluid mixture of food and gastric fluid.

duodenum

After food is digested in the stomach, the chyme goes into _____.

Cardiac

Fundus

Body

Pylorus

What are the four regions of the stomach?

Cardiac

The entryway from the esophagus

Mucosa, Submucosa, Muscularis, Serosa

What are the four layers of the stomach?

Oblique muscle

Gives the stomach wall a criss-cross pattern which allows the stomach to contract and churn vigorously as it processes food.

Serosa

Outermost tunic of the stomach.

Rugae

When the stomach is empty the mucosa and submucosa wrinkles into folds, called ___.

Gastric pits

The gastric mucosa contains depressions called ______.

Gastric juice

Gastric glands secrete the various components of _____ (2-3 liters/day)

4 hours

The stomach empties how many hours with liquid meals?

6 hours

The stomach empties how many hours with high fat meals?