A&P II Test 1 Study Guide- Digestive System

What is the function of secretin (at least two)?

1. Causes pancreas to make pancreatic juice rich in bicarbonate 2. Decreases stomach secretion and shuts down the stomach when food reaches the duodenum 3. Increases bile production of the liver 4. Acidic chyme enters the duodenum

What is the function of CCK (At least 4)?

1. Causes the gallblasser to contract and release bile after a fatty meal 2. Causes the pancreas to make pancreatic juice rich in digestive enzymes 3. Decreases stomach secretions and shuts down the stomach when food reaches the duodenum 4. Acts on the hypothalamus to make a person feel full

Name 4 type of specialized epithelial cells found in the mucosa of the stomach

1. Goblet cells 2. Chief cells 3. Parietal cells 4. Enteroendocrine G-cells

What is the function of the gastrin (at least two)?

1. Increases stomach secretion 2. Promotes digestion and stomach emptying 3. Increased acid production

Name the 4 basic histology layers of organs of the GI tract.

1. Mucosa 2. Submucosa 3. Muscularis Externa 4. Serosa

Name the 3 anatomical part of the pharynx

1. Oropharynx 2 Laryngopharynx 3. Nasopharynx

4 components of saliva

1. Water 2. Mucus 3. Lysosome 4. Ions

What is the name of the peritoneum that hangs from the greater curvature of the stomach?

Greater Omentum

How is HCl made by the parietal cell?

H+ ions are secreted by the parietal cell into the lumen of the gastric gland, Acid from carbon dioxide and water. The H+ that are produced are pumped into the lumen of the gastric gland.

What activates the proenzyme, pepsinogen?

HCl

Condition when a portion of the stomach protrudes through the diaphragm into those thoracic cavity

Hiatal hernia

What stimulates the secretion of HCl from the parietal cell?

Histamine

What is the significance of intrinsic factor?

Important for the absorption of vitamin B12 which is important for normal functioning of the brain, nervous system and the production of red blood cells

What is a proenzyme?

Inactive form of an enzyme that prevents digestion of the proteins in the lining organs

The four front teeth ( located on the mandible and maxilla) used for cutting, clipping, and gnawing food

Incisor- Where is it found? what is its significance?

In which of these phases are hormones involved? What hormones?

Intestinal phase= CCK and Secretin

Epiglottis- What is the significance? Where are they located? Type of cells/ tissues make up the structure?

It flaps over the opening of the larynx to make sure that food passes down the esophagus and not the trachea. Located at the top of the larynx or voice box. It is made of elastic cartilage

Periodontal Ligament- What is the significance? Where are they located? Type of cells/ tissues make up the structure?

It is a ligament that connects the tooth to the alveolar socket of the bone. made of fibrous connective tissue

Parotid Gland- Histology, Does the gland contain primarily mucus acini, serous acini, or relatively equal amount of both?

It is made of contractile myoepithelial cells and acinus cells . Produces serous solution, and has a long duct, mucus would not easily be able to move though the duct from the parotid gland.

Name the retroperitoneal organs of the GI tract.

Kidneys. pancreas, ascending and descending colon, rectum, duodenum

Name the functions of HCl in the stomach

Kills bacteria. activates pepsinogen, and denatures proteins

When a person cannot digest food with lactose in them. Lactose is the sugar found in milk and food made with milk.

Lactose Intolerant

Tonsils- What is the significance? Where are they located? Type of cells/ tissues make up the structure?

Lymphatic tissue on each side of the oropharynx that helps to fight infection. They have a surface of stratified squamous epithelium, and contains white blood cells, and other cells that are important in immune defense

In which organ is Gastrin made? Which cells make it? Target organ? What causes it to secrete?

Made in the stomach, targets the stomach, Produced by the enteroendocrine G-cells, HCl causes gastrin to be secreted

What is the basic function of the tongue?

Manipulating food into a bolus

What is the basic function of the teeth?

Mechanical digestion= mastication

What is the name of the peritoneum that connects the small intestine to the posterior wall of abdominal cavity?

Mesentary Proper

What is the difference between microvilli, villi, rugae, and plicae circulares?

Microvilli- forms a brush border Villi- in the epithelium and lamina propia of the mucosa Rugae- folds in the simple columnar epithelium of the stomach Plicae Circulares- folds in the submucosa and the mucosa

Teeth that are located in the back of the mouth, they are used for grinding and has a wider crown

Molar- Where is it found? what is its significance?

Name the structure of the actual GI tract from mouth to anus

Mouth, oropharynx, laryngopharynx, esophagus, stomach, small intestine (duodenum, jejunum, and illeum), and large intestine (cecum, ascending colon, transverse colon, descending colon, sigmoid colon, rectum)

What is unique about the muscularis of the sphincter?

Myenteric plecus that controls peristalysis

What is the difference between the enteric and parasympathetic nervous system?

Parasympathetic nervous system increases motility and secretion in the GI tract. Major parasympathetic nerve innervating GI organs in the vagus nerve Enteric nervous system- helps control the motility and secretion. includes the myenteric plexus, and submucosal plexus, includes sensory neurons that can detect the presence of certain food.

Name the three major salivary gland

Parotid Gland, Submandibular and sublingual

Wave- like contractions of the circular and longitudinal layers of muscles throughout the GI tract that help to propel food forward

Peristalsis

Serous membrane that lines the abdominal cavity

Peritoneum

Inflammation of the peritoneum due to rupture of the intraperitoneal organ

Peritonitis

What is the function of the enteroendocrine cells?

Produce the hormone gastrin, secrete serotonin, and secretes histamine

What is the basic function of the liver?

Produces bile needed for fat digestion

An uncommon condition in infants that blocks food from entering the small intestine

Pyloric Stenosis

What is the function of parietal cells?

Secrete HCl and intrinsic factor

What is the function of Goblet cells?

Secrete mucus to protect the epithelium/ stomach from acidic pH of gastric juices

What is the function of the chief cells?

Secretes zymogen pepsinogen

What is the difference in the serosa and adventitia?

Serosa is made of visceral peritoneum adventitia is parietal peritoneum

Sublingual Gland- Histology, Does the gland contain primarily mucus acini, serous acini, or relatively equal amount of both?

Shortest duct out of all the salivary glands. Composed of mucous acini. Produces primarily mucus acini.

What is the basic function of the gallbladder?

Stores, delivers and concentrates bile

Which salivary gland has the longest duct? Why is it significant?

Submandibular gland because it secretes a watery fluid so it will be able to travel a longer distance without having trouble going through the duct, and will not block the duct

Gingiva- What is the significance? Where are they located? Type of cells/ tissues make up the structure?

The gums, it is located around the teeth, and contains blood vessels, gingiva contains statified squamous epithelium

Explain Mastication

The mechanical process of chewing, grinding food into small pieces by the teeth

Explain Deglutition (including the phases)

The process of swallowing food occuring in 3 phases: Buccal, pharyngeal phase, and esophageal phase

Explain control of the gastric secretion in the cephalic phase

The thinking about eating, the hypothalamus stimulates the parasympathetic nervous system. Vagus nerve initiates formation and secretion of gastric juices

What makes the muscularis externa of the stomach unique?

There is three layers of smooth muscle (inner, oblique, middle circular layer, and an outer longitudinal layer) that allows the stomach to churn food and form chyme

Name the accessory digestive organs.

Tongue, teeth, Liver, gallbladder, pancreas and Salivary glands

A small conic projection off the soft palate that prevents premature deglutition of food down the esophagus

Uvula- Where is it found? what is its significance?

Explain the nervous control of the gastric phase

Vagus nerve and the pelvis splanchin nerves sends ganglionic parasympathetic fibers, to synapse with enteric neurons

Is peritoneum a serous membrane? What does that mean?

Yes, it lines the walls of the abdominal cavity to keep organs attached

Describe the tissue in the Serosa

aerolar tissue with simple squamous

Esophagus phase

bolus moves into esophageal= peristalsis- which is smooth muscle of circular and longitudinal lower esophageal sphincter opens so food can go into the stomach

Pharyngeal phase

bolus moves into oropharynx- skeletal muscle constricts, larynx is elevated, and epiglottis closes

Significance of the upper esophageal sphincters

comprised of skeletal muscle, meaning we have voluntary control over it. Upper esophageal sphincter will open and relax and allow the bolus to pass through

what is the basic function of the pancreas?

contains pancreatic juice that has a lot of digestive enzymes: Trypsin, chymotrypsin, lipase, amylase

Describe the tissue in the mucosa

epithelium- stratified squamous, and simple columnar lamina propria- areolar muscular is mucosa- stratified squamous

In which organ is CCK made? Which cells make CCK? Target organ? What causes it to secrete?

it is made by the duodenum by enteroendocrine cells. when fatty rich food enters the duodenum CCK is secreted

What is the name of the peritoneum that connects the liver to the stomach?

lesser omentum

In which organ is secretin made? Which cells make it? Target organ? What causes it to secrete?

made in the duodenum, what causes it to secrete is when acidic chyme enters the duodenum, cell that makes it is s cells.

What is the purpose of mucus and serous acini?

mucus acini is mucus rich saliva serous acini is secretes watery fluid

Which nerve plexus plays a role in peristalsis?

myenteric plexus

what does it mean to say that an organ is intraperitoneal?

organ that is completely surrounded by peritoneum (stomach, liver, spleen)

What is the basic function of the salivary glands?

produces saliva that contains mucus and digestive enzyme amylase

What type of epithelium is in the nasalpharynx?

pseudostratified columnar

How does the autonomic nervous system affect peristalsis?

rest and digest- increases peristalsis

What type of tissue is found in the peritoneum?

simple squamous epithelium and areolar connective tissue

What organs are involved in deglutition?

skeletal muscle, smooth muscle, glossopharyngeal nerve, vagus nerve, and hypoglossal

Describe the tissue in the muscularis externa

smooth muscle

Name the intraperitoneal organs of the GI tract.

stomach, liver, spleen, gallbladder, jejunum, ileum, transverse colon, sigmoid colon

What type of epithelium is in the Laryngopharynx?

stratified Squamous

What type of epithelium is in the oropharynx

stratified squamous

What organs are involved in mastication?

teeth, jaw, masseter muscle, trigeminal nerve

When do the esophageal sphincters open and close?

upper esophageal sphincter opens to allow a bolus to move Lower esophagus Sphincter closes to prevent the bolus from coming back up

Buccal phase

voluntary manipulating the bolus of food to the back of the tongue

Where is microvilli located? What is its purpose?

Cellular surface extensions on villi that form a brush border, increases surface area and allows for more absorption

Explain control of the gastric secretion in the intestinal phase

Chyme reaches the duodenum, stomach should stop churning and secreting gastric juice. As duodenum is stretched it stops activation of parasympathetic nervous system. Hormone control- CCK (cholecystoknin)- made when fat enters duodenum, causes gallbladder to contract shuts stomach down and increases pancreatic enzymes.

Acidic milky white substance of food mixed with gastric juice

Chyme- Where is it found? what is its significance?

Why are two layers of muscularis necessary for peristalsis?

Circular and longitudinal layers

Submandibular Gland- Histology, Does the gland contain primarily mucus acini, serous acini, or relatively equal amount of both?

Composed of mucous acini, Acinar glands with simple cuboidal ducts. Produces both mucus and serous fluid.

Describe the tissue in the submucosa

Dense connective tissue

cellular calcified tissue that compromises most of the tooth, it is the structure of the tooth

Dentin- Where is it found? what is its significance?

Hard calcium salt on the crown of the tooth, it helps to protect the tooth

Enamel- Where is it found? what is its significance?

Explain control of the gastric secretion in the gastric phase

Enteric nervous system (detects stretch and higher pH. Enteric neurons together with autonomic nervous system stimulate mechanical churning (the creation of chyme). Under control by hormones, gastrin is released when the stomach is stretched. binds to receptors on parietal cells causes pumping of H+ ions into stomach lumen, increase motility of stomach, closes esophageal sphincter

Explain the nervous control of the intestinal phase

Enterogastric reflex for shutting down the stomach

What organs in the GI tract undergo peristalsis?

Esophagus, stomach, small intestine and large intestine

What is the name of the peritoneum that connects the liver to the anterior abdominal wall?

Falciform Ligament

For what length of time is food in the stomach? Is any food absorbed in the stomach?

Food is generally in the stomach for 3-4 hours. Food and nutrients are not absorbed in the stomach but some liquids such as caffeine and alcohol can be, tear the lining of the stomach

A fold of mucous membrane that connects the lips with the gums and attaches the tongue to the floor of the mouth, it is significant because it holds the structures in place

Frenulum- Where is it found? what is its significance?

a crystallization of excess cholesterol that can lead to obstruction of the bile duct

Gallstones

it is an open sore in the lining of the stomach that is caused by stress or colonization by the Helocobacter Pylori

Gastric Ulcer

Occurs when stomach acid frequently flow back into the tube connecting your mouth and stomach (esophagus). This backwash can irritate the lining of the esophagus

Gastroesophageal Reflux

inflammation of the gums

Gingivitis

Significance of the lower esophageal sphincters

A small band of muscles at hte lower end of the esophagus. Contracts to prevent the bolus from coming back up into the esophagus

Explain the nervous control of the cephalic phase

Activating the Vagus nerve to being secreting gastric acid and initiates churning

A ball of food created by the teeth and the tongue. It is found in the mouth and it moves down the digestive track. Its significant because it is the way that the body

Bolus- Where is it found? what is its significance?