Module 10: Digestive System Flashcards
What comprises the digestive system?
(1) Alimentary canal (straight or linear path)
(2) Accessory Organs
What comprises the Alimentary Canal?
mouth, pharynx, esophagus, stomach, small intestine, large intestine
What comprises the Accessory Organs?
teeth, tongue, gallbladder, salivary glands, liver, pancreas
This major process involves the taking food into the digestive tract. It is one of the major roles of the mouth.
Ingestion
This major process involves moving food through the canal,
includes swallowing and peristalsis. It mainly involves the mouth, pharynx, and the esophagus due to peristalsis.
Propulsion
This major process involves preparing for digestion by enzymes, included chewing, mixing with saliva, churning in the stomach, segmentation.
Mechanical Breakdown
This major process involves enzymatic degradation of food
molecules. This is the major role of the small intestine and stomach.
Digestion
This major process involves the passage of end-products from lumen to blood or lymph.
Absorption
This major process involves the elimination of indigestible substances. It involves your sigmoidal colon and the anus.
Defecation
This is the most extensive membrane in the abdominopelvic cavity that is composed of layer of smooth epithelial tissue. It extends over your body’s surface area.
Peritoneum (derived from the Greek word peritonion, which means to stretch round)
This peritoneum covers the external surface of digestive organs.
Visceral Peritoneum
This peritoneum lines the body wall.
Parietal Peritoneum
This potential space containing fluid secreted by serous membranes which allows digestive organs to glide easily across one another.
Peritoneal Cavity
This is a double layer of peritoneum that 1) provide routes for blood vessels, lymph and nerves, 2) holds organ in place, 3) store fat
Mesentery
This is the connective tissue of organs in the abdominal cavity
Mesentery
This is a form of mesentery connecting lesser curvature of stomach to liver and diaphragm
Lesser Omentum
This is a form of mesentery connecting greater curvature of the stomach to transverse colon and posterior body wall
Greater Omentum
What are the three salivary glands that aids in the formation of the saliva?
(1) Parotid
(2) Sublingual
(3) Submandibular
This part of the saliva aids your immune system.
Immunoglobulin
How much fluid does peritoneal cavity contain?
100 mL (serous fluid)
This condition pertains to the inflammation of the peritoneum due to the friction between the visceral and parietal peritoneum, thus leading to a board like abdomen.
Peritonitis
Are there any organs in the peritoneum?
No, but all the organs in the system is contained in the abdominopelvic cavity.
How does the peritoneum play an important part for patients with kidney problems?
The peritoneum is used to clear out the blood of patients that have none functioning kidneys.
This pertains to the posterior region of the peritoneum, where the pancreas, the kidneys, and the duodenum, as well as the rectum and the urinary bladder are located.
Retroperitoneum
What are the four (4) tunics of the alimentary canal?
(1) Mucosa
(2) Sub-mucosa (under the mucosa)
(3) Muscularis externa
(4) Serosa (exterior tunic)
The mucosa is constituted of what?
(1) Epithelium
(2) Lamina propria
(3) Muscularis mucosae
The muscularis externis is composed of what?
(1) circular layer
(2) longitudinal layer
(3) oblique layer (which allows churning)
The serosa is composed of what?
(1) connective tissue
(2) Epithelium (mesothelium)
This layer is where mucus is produced which aids in propelling the food down to the alimentary canal.
Mucosa layer (muscularis mucosae)
In this layer, this is where the blood vessels, the lymph, and the nerves run.
Submucosa
What is the relationship between the glands of the submucosa and the mucosa?
The glands in the submucosa is connected to the mucosa which allows the secretion of enzymes and hormones to the alimentary canal.
This layer is composed of a circular and longitudinal layer that allows the process of propulsion, segmentation and peristalsis down to the alimentary canal with the use of muscles.
Muscularis Externis
If the serosa is not connected to any peritoneum, then it is called “____________”
Adventitia
This pertains to the hollowed openings.
Lumen
This is the condition wherein the hiatus slides to a hollowed opening.
Hiatal Hernia
This is the condition when the canal weakens which leads to outpouching of the hiatus.
Herniation
This helps in taking in and excreting the blood or fluid during blood flow.
abdominal aorta
This anatomical structure helps in the perfusion.
Superior mesenteric artery
What are the branches of the mesenteric artery which allows for blood flow for the upper area of the abdominopelvic cavity.
(1) Middle Colic artery
(2) Intestinal artery
(3) Right Colic Artery
(4) Ileocolic Artery
What are the branches of the mesenteric artery which allows for blood flow for the lower area of the abdominopelvic cavity.
(1) Left colic artery
(2) Sigmoidal artery
(3) Superior rectal artery
This innervates and supplies blood in the abdominopelvic cavity in terms of arterial blood flow.
Mesenteric artery
This condition pertains to the presence of edema in the patient’s abdominopelvic cavity.
Asities
This condition pertains to the problem in the portal hepatic vein, which connects the blood supply of the abdomen and the liver as well as the major veins.
Portal Hypertension
This vein connects the blood supply of the abdomen and the liver as well as the major veins
Portal Vein
This pertains to the collection of venous rich blood from the viscera to the liver.
Hepatic Portal Circulation
How much cardiac output does the stomach receive after ingestion?
1/4
This reflex occurs because the abdominal region receives 1/4 of your cardiac output, which results to the decrease in blood flow in your brain or decrease in perfusion.
Splanchnic Reflex
What are the two connections in the enteric nervous system from the CNS to the PNS?
(1) Submucosal Nerve Plexus
(2) Myenteric Nerve Plexus
This is the in-house nerve supply of the alimentary canal that regulates digestive system activity and innervates to the abdominal cavity.
Enteric Nervous System
Explain the flow in the enteric nervous system.
(1) Internal Stimuli (changes in the GI tract stretch, lumen pH, or solute concentration.
(2) The chemoreceptors (chemical), osmoreceptors (pressure), or mechanoreceptors (stretch) will convey the internal stimuli the CNS
(3) You can also receive external stimuli from the sight, smell, taste, and thought of the food.
(4) The stimulus will travel to the local (intrinsic nerve plexus or the gut brain to the effectors like smooth muscle or glands
(5) Therefore, resulting to a response like changes in contractile and secretory activity
This occur entirely within the gastrointestinal wall and is in charge of stimuli.
Short Reflexes
This is called the oral cavity, bounded by lips in the anterior, cheeks laterally, palate superiorly and tongue inferiorly
Mouth
The mouth continues with the ______________.
Oropharynx
The mouth is line with what?
Lined with stratified squamous epithelium (withstands friction) and slightly keratinized to prevent abrasion while eating
This is the pouch-like structure that allows storage.
Oral Vestibule
These are salivary glands that allows the secretion of saliva, which then prompts the initial stage of digestion.
Submandibular and sublingual ducts
This is a small flesh that is responsible for the gag reflex.
Uvula
This is a common passage for food, water and air, wherein the epiglottis closes to block the larynx so the patient does not aspirate food and water.
Laryngopharynx
What are the three (3) salivary glands?
(1) Parotid
(2) Sublingual
(3) Submandibular
This salivary gland is located in the anterior portion of your ear. It has ducts that allow secretions to be delivered into the oral cavity.
Parotid Salivary gland
This salivary gland is located below the jaw.
Submandibular salivary gland
This salivary gland is located inferior to the tongue.
Sublingual salivary gland
What are the functions of the salivary glands?
(1) Cleanses the mouth
(2) Dissolves the food chemicals for
tasting
(3) Moisten foods and helps compact it a bolus
(4) Contains amylase to digest starchy foods
This is an enzyme responsible for breaking down or digestion of starch.
amylase (salivary amylase)
What are the three (3) kinds of pharynx?
(1) Nasopharynx (connected to the nose)
(2) Oropharynx (connected to the oral cavity)
(3) Laryngopharynx
This is the pharynx or common passage of food, fluid, and air.
Laryngopharynx
This is a muscular tube about 25cm and collapsed when not propelling food
Esophagus
What happens to the epiglottis when food moves through the laryngopharynx?
Once food moves through the laryngopharynx, epiglottis will close the larynx and food will posteriorly move to the esophagus and not to the trachea
This is surrounded by circular smooth muscle that keeps it closed when food is not being swallowed.
Gastroesophageal sphincter (Cardiac Sphincter)
These help protect the tube from reflux of stomach acid.
Mucous cells at the sides
This sphincter posterior to the pharynx prevents the backflow of blood and food going back to your oral cavity, which is a closing area.
Upper esophageal sphincter
This sphincter is also known gastroesophageal sphincter that is a connection between your stomach and esophagus.
Lower esophageal sphincter
What happens when you eat too much and you have a weak esophageal sphincter?
The patient will get heart burn due to the reflux. Hence it is important to not lie down after ingesting many food.
What are three (3) phases in the pharynx in terms of food propulsion?
(1) Buccal phase
(2) Pharyngeal-esophageal phase
(3) Pharyngeal-esophageal phase continues
Explain the buccal phase.
The upper esophageal sphincter is contracted (closed). The tongue presses against the hard palate, forcing the food bolus into the oropharynx.
Explain the pharyngeal-esophageal phase.
(1) The tongue blocks the mouth. The soft palate and its uvula rise, closing off the nasopharynx.
(2) The larynx rises so that the epiglottis blocks the trachea. The upper esophageal sphincter relaxes, food enters the esophagus.
Explain the continuation of the pharyngeal-esophageal phase.
(1)The constrictor muscles of the pharynx contract, forcing food into the esophagus inferiorly
(2) The upper esophageal sphincter contracts after food enters.
(3) Peristalsis moves food through the esophagus to the stomach (circular and longitudinal muscles contract to allow food to move down)
(4) The gastroesophageal sphincter surrounding the cardial orifice opens. After the food enters the sphincter closes to prevent regurgitation
This is a wave of contraction moves food through digestive tract.
Peristalsis
How does peristalsis work?
(1) A wave of smooth muscle relaxation moves ahead of the bolus, allowing the digestive tract to expand.
(2) A wave of contraction behind the bolus propels it (squeezes it to move) through the digestive tract.