Term 4 Digestive System Flashcards
What are the two groups of organs in the digestive system?
- _______\_ – alimentary canal, ~5-7 m long, a tube extending from the mouth to the anus through the ventral body cavity
- ________\_ – assist the digestion process e.g. mechanically and enzymatically breaking down food
What are the two groups of organs in the digestive system?
- Gastrointestinal (GI) tract – alimentary canal, ~5-7 m long, a tube extending from the mouth to the anus through the ventral body cavity
- Accessory digestive organs – assist the digestion process e.g. mechanically and enzymatically breaking down food
Gastrointestial (GI) tract Includes:
- ____\_
- ____\_
- ____\_
- ____\_
- ____\_
- ____\_
Gastrointestial (GI) tract Includes:
- Mouth
- Pharynx
- Esophagus
- Stomach
- Small intestine
- Large intestine
Accessory organs include:
- _____\_
- _____\_
- _____\_
- _____\_
- _____\_
- _____\_
Accessory organs include:
- Teeth
- Tongue
- Salivary glands
- Liver
- Gall bladder
- Pancreas
The GI tract is composed of four basic layers:
- _________
- _________
- ________
- ________
The GI tract is composed of four basic layers:
- Mucosa (deep)
- Submucosa
- Muscularis
- Serosa or adventitia (superficial)
Inner lining of GI tract is a mucous membrane containing:
- ______\_– specialized in absorbing digestive nutrients and contains enteroendocrine cells
- ______\_ – areolar connective, blood and lymphatic vessels and MALT
- ______\_– smooth muscle fibres whose movement increase surface and ensures all absorptive cells are exposed to GI content
Inner lining of GI tract is a mucous membrane containing:
- Epithelial cells – specialized in absorbing digestive nutrients and contains enteroendocrine cells
- Lamina propria – areolar connective, blood and lymphatic vessels and MALT
- Muscularis mucosa – smooth muscle fibers whose movement increase surface and ensures all absorptive cells are exposed to GI content
- The _______ is:
- Thin meshwork of collagenous fibres, nerves and blood vessels
- Areolar connective tissue binds the mucosa to the middle layer (muscularis)
- Highly vascular
- Contains the submucosal plexus (plexus of Meissner)
Submucosa
Muscularis:
- Consist of smooth muscle
- Inner sheet of _____\_
- Outer sheet of _____\_
- Contains the ______\_ (plexus of Auerbach)
- Controls _________(movement of chyme)
Muscularis:
- Consist of smooth muscle
- Inner sheet of circular fibers
- Outer sheet of longitudinal fibers
- Contains the myenteric plexes (plexus of Auerbach)
- Controls GI tract motility (movement of chyme)
Serosa (Adventitia):
- ______\_ layer of the GI tract
- A ______\_ composed of areolar connective tissue and simple squamous epithelium (mesothelium)
- The epithelium is also called the ______\_ as it forms the peritoneum that surrounds organs that are suspended in the peritoneal cavity
- Secretes a ______\_
- Derived from ______\_ of surrounding tissue
Serosa (Adventitia):
- Superficial layer of the GI tract
- A serous membrane composed of areolar connective tissue and simple squamous epithelium (mesothelium)
- The epithelium is also called the visceral peritoneum as it forms the peritoneum that surrounds organs that are suspended in the peritoneal cavity
- Secretes a serous fluid
- Derived from interstitial fluid of surrounding tissue
-_______\_is a single layer of areolar connective tissue that surround the esophagus and lower aspects of the rectum (these lack serosa)
Adentitia is a single layer of areolar connective tissue that surround the esophagus and lower aspects of the rectum (these lack serosa)
_______\_ is the largest serous membrane of the body and is divided into 2 portions:
- _______\_ – lines the wall of the peritoneal cavity
- _______\_ (serosa)
-
_______\_ is the space between the parietal and visceral peritonea
- Contains __________fluid
Peritoneum is the largest serous membrane of the body and is divided into 2 portions:
- Parietal peritoneum – lines the wall of the peritoneal cavity
- Visceral peritoneum (serosa)
-
Peritoneal cavity is the space between the parietal and visceral peritonea
- Contains serous fluid
The Peritoneum contains 7 major fat-filled folds:
Which two can be seen in the attached image:
- ______\_ – largest, drapes over the transverse colon and the coils of the small intestine like a “fatty apron”
- ______\_– attaches liver to the anterior abdominal wall and diaphragm
The Peritoneum contains 7 major fat-filled folds:
Which two can be seen in the attached image:
- Greater omentum – largest, drapes over the transverse colon and the coils of the small intestine like a “fatty apron”
- Falciform ligament – attaches liver to the anterior abdominal wall and diaphragm
The Peritoneum contains 7 major fat-filled folds:
Which one can be seen in the attached image:
- _____\_ – suspends the stomach and duodenum from the liver
- Lesser omentum – suspends the stomach and duodenum from the liver
The peritoneum contains 7 major fat-filled folds
Which one can be seen in the attached image?
- ______ – fan-shaped; binds the jejunum and ileum to the posterior abdominal wall
Mesentery – fan-shaped; binds the jejunum and ileum to the posterior abdominal wall
What are the 3 pairs of major salivary glands?
-
______\_
* Parotid (Stensen’s) duct opens into the ______\_opposite the ______\_ tooth -
______\_ – located beneath the tongue
* Submandibular (Wharton’s) ducts opens into the ______\_on either side of the ______\_ -
______\_ - located in the floor of the mouth, superior to the submandibular glands
* Lesser sublingual (Rivinus’) ducts open into the ______\_
What are the 3 pairs of major salivary glands?
-
Parotid glands
* Parotid (Stensen’s) duct opens into the vestibule opposite the second maxillary molar tooth -
Submandibular glands – located beneath the tongue
* Submandibular (Wharton’s) ducts opens into the oral cavity on either side of the lingual frenulum -
Sublingual glands - located in the floor of the mouth, superior to the submandibular glands
* Lesser sublingual (Rivinus’) ducts open into the floor of the mouth
The tongue is an accessory digestive organ composed of _____\_muscle covered with _____\_
The tongue is an accessory digestive organ composed of skeletal muscle covered with mucous membrane
______\_ is a fold of mucous membrane that connects the tongue to the floor of the mouth
Lingual frenulum – fold of mucous membrane that connects the tongue to the floor of the mouth
The tongue is divided into lateral halves by a ____ _____ ______
- inferiorly, this attaches to the _______
The tongue is divided into lateral halves by a median fibrous septum
- inferiorly, this attaches to the hyoid bone
Tongue muscles are of two types:
- _______\_ - originate outside the tongue and insert into it, moving the entire tongue in various directions
-
_______\_ - originate and insert within the tongue, altering the tongue’s shape
- Named by the direction of the muscle fibres – anterior longitudinal, posterior longitudinal, transverse and lateral
Tongue muscles are of two types:
- Extrinsic tongue muscles - originate outside the tongue and insert into it, moving the entire tongue in various directions
-
Intrinsic tongue muscles - originate and insert within the tongue, altering the tongue’s shape
- Named by the direction of the muscle fibres – anterior longitudinal, posterior longitudinal, transverse and lateral
Extrinsic muscles that move the tongue
- _______\_ – depress and protracts (stick out) tongue
- _______\_ – elevates and retracts tongue
- _______\_ – depresses tongue and draws down its sides
- _______\_ – elevates posterior portion of the tongue
Extrinsic muscles that move the tongue
- Genioglossus – depress and protracts (stick out) tongue
- Styloglossus – elevates and retracts tongue
- Hyoglossus – depresses tongue and draws down its sides
- Palatoglossus – elevates posterior portion of the tongue
The teeth:
- sit in sockets of ______\_ of the ______ (bone) and ______ (bone)
- Alveolar processes are covered by _____\_(gums) that extend slightly to form the _____\_
- Sockets are lined by _____\_ ligament that anchors teeth and absorbs shock when chewing
The teeth:
- sit in sockets of alveolar processes of the mandible and maxillae
- Alveolar processes are covered by gingivae (gums) that extend slightly to form the gingival sulcus
- Sockets are lined by periodontal ligament that anchors teeth and absorbs shock when chewing
Teeth consist of three major regions:
- visible portion above the gum line
- 1 to 3 embedded in the socket
- junction between crown and root, near gum line
Teeth consist of three major regions:
- Crown- visible portion above the gum line
- Roots - 1 to 3 embedded in the socket
- Neck - junction between crown and root, near gum line
Most of the tooth is ______.
Label ^ along with the following structures that make up the tooth:
- Pulp cavity
- Root Canals and their openings:
- Apical foramen
- Enamel
- Cementum
The_______ (milk teeth) begin to erupt at ~6 months old
- One pair appears every month until 20 teeth present (~2 yrs old)
The Deciduous teeth (milk teeth) begin to erupt at ~6 months old
- One pair appears every month until 20 teeth present (~2 yrs old)
There are 32 _______\_ that appear between age 6 and adulthood (~21 yrs old)
There are 32 permanent teeth that appear between age 6 and adulthood (~21 yrs old)
The _____ (throat) extends from the internal nares to the esophagus posteriorly and the larynx anteriorly.
It is composed of ______ muscle and lined by ________
The pharynx (throat) extends from the internal nares to the esophagus posteriorly and the larynx anteriorly.
It is composed of skeletal muscle and lined by mucous
Which of the following structures only function in respiration?
- Nasopharynx - only respiration
- Oropharynx - digestive and respiratory functions
- Laryngopharynx
- Nasopharynx - only respiration
- Oropharynx - digestive and respiratory functions
- Laryngopharynx - digestive and respiration
What is deglutition?
Term for swallowing:
mechanism that moves food (bolus) from the mouth, through the pharynx and to the stomach
The _____ is a muscular, collapsible tube from the laryngopharynx to the stomach
Esophagus
The esophagus lies in the _______ (anterior to the _____ and posterior to the ______) and passes through the ________ in the diaphragm
The esophagus lies in the mediastinum (anterior to the spine and posterior to the trachea) and passes through the esophageal hiatus in the diaphragm
The wall of the esophagus is composed of the following 4 layers:
- ______ - contains glands near stomach
- ______ - contains glands and elastic fibres
- ______ - skeletal and smooth muscle
- ______ - areolar connective tissue but not covered by epithelium
The wall of the esophagus is composed of the following 4 layers:
- Mucosa - contains glands near stomach
- Submucosa - contains glands and elastic fibres
- Muscularis - skeletal and smooth muscle
- Adventitia - areolar connective tissue but not covered by epithelium
The esophagus has two functions:
- secrete ____
- transport _____-
The esophagus has two functions:
- secrete mucus
- transport food into the stomach
The ________ sphincter (pharyngeosophageal sphincter) controls entry of food into the esophagus
The Upper esophageal sphincter (pharyngeosophageal sphincter) controls entry of food into the esophagus
Elevation of the _____ during swallowing causes the UES (________) to relax and bolus enters the esophagus
Elevation of the larynx during swallowing causes the UES (upper esophageal spincter) to relax and bolus enters the esophagus
The _______ sphincter (aka gastroesophageal or cardiac sphincter) controls entry of food into the stomach
The lower esophageal sphincter (aka gastroesophageal or cardiac sphincter) controls entry of food into the stomach
Esophageal glands secrete ____ to reduce friction
mucus
The stomach lies inferior to the ______in the left ______ region of the abdominal cavity
The stomach lies inferior to the diaphragm in the left hypochondriac region of the abdominal cavity
The stomach connects the _____ to the ______
The stomach connects the esophagus to the duodenum
What are the four main areas of the stomach?
- ______
- ______ - storage of food
- ______
- ______ - contains 3 regions:
- ______ - connects to the stomach body
- ______ - leads to pylorus
- ______ - opening of the pyloric sphincter
What are the four main areas of the stomach?
- Cardia
- Fundus - storage of food
- Body
-
Pylorus - contains 3 regions:
- Pyloric antrum - connects to the stomach body
- Pyloric canal - leads to pylorus
- Pylorus - opening of the pyloric sphincter
Large mucosa folds of the stomach are called _____
rugae
The concave medial border of the of the stomach is called the _______
lesser curvature
The convex lateral border of the stomach is called the ________
Greater curvature
What are the four layers of the stomach?
- ________ - contains mucus-secreting surface mucous cells (where rugae is found)
- ________ - Composed of areolar CT
- ________ - Has 3 layers of smooth muscle:
- _______
- _______
- _______
- ______ - composed of simple squamous epithelium
What are the four layers of the stomach?
- Mucosa - contains mucus-secreting surface mucous cells (where rugae is found)
- Submucosa - Composed of areolar CT
-
Muscularis - Has 3 layers of smooth muscle:
- Outer Longitudinal layer
- Middle Circular layer
- Inner Oblique layer
- Serosa - composed of simple squamous epithelium
Name the cells of the gastric glands based on the description:
- _________ - secrete mucus
- _________ - secrete enzymes
- pepsinogen
- gastric lipase
- ________ - Secrete HCl (activates pepsinogen into pepsin and creates acidic pH (2.3) for pepsin)
- __________ - secrete hormone gastrin into the blood; gastrin stimulates the _____ cells
Name the cells of the gastric glands based on the description:
- mucous neck cells - secrete mucus
-
Chief (zymogenic) cells - secrete enzymes
- pepsinogen
- gastric lipase
- Parietal cells - Secrete HCl (activates pepsinogen into pepsin and creates acidic pH (2.3) for pepsin)
- G Cells - secrete hormone gastrin into the blood; gastrin stimulates the parietal cells
What organ is located posterior to the greater curvature of the stomach?
Pancreas
The pancreas has a major ______ function - secretes pancreatic juice
The pancreas has a major exocrine function - secretes pancreatic juice
Pancreatic juice contains:
- _______ - neutralizes gastric pH in chyme, inactivates pepsin, provides optimal pH for digestive enzymes in the small intestine
- Digestive enzymes:
- _______ - digest carbs
- ______ - trypsin, chymotrypsis, carboxypeptidase, elastase
- ______ - digests triglycerides (lipids)
- ______ - digests RNA
- ______ - digests DNA
Pancreatic juice contains:
- Bicarbonate - neutralizes gastric pH in chyme, inactivates pepsin, provides optimal pH for digestive enzymes in the small intestine
- Digestive enzymes:
- Pancreatic amylase - digest carbs
- Proteases - trypsin, chymotrypsis, carboxypeptidase, elastase
- Pancreatic lipase - digests triglycerides (lipids)
- Ribonuclease - digests RNA
- deoxyribonuclease - digests DNA
The pancreas consists of 3 major regions:
- _____ - located near the curve of the duodenum, from which the _______ projects
- ____
- _____ - lateral, tapered
The pancreas consists of 3 major regions:
- Head - located near the curve of the duodenum, from which the uncinate process projects
- Body
- tail - lateral, tapered
The pancreatic duct joins the common bile duct to form the __________
The pancreatic duct joins the common bile duct to form the hepatopancreatic ampulla (ampulla of vater)
The two ducts that empty pancreatic juice into the _____ are the:
- ________ duct
- _________
The two ducts that empty pancreatic juice into the duodenum are the:
- pancreatic duct
- accessory duct
Hepatic blood flow:
what is the path of bile flow from the liver to the duodenum
There are three ways that the liver can be organized into anatomical and functional units: label the italicized structures
- __________
- __________
- __________
- Hepatic Lobule
- Portal Lobule
- Hepatic acinus
The Hepatic Lobule is a hexagonal-shaped structure consisting of ______\_organized into ______\_ along ________\_ that radiate from a central vein
The Hepatic Lobule is a hexagonal-shaped structure consisting of hepatocytes organized into hepatic laminae along hepatic sinusoids that radiate from a central vein
The portal lobule organization emphasizes the _______ function of the liver - bile secretion and thus has the _____ duct at the center of the portal lobule
The portal lobule organization emphasizes the _______ function of the liver - bile secretion and thus has the _____ duct at the center of the portal lobule
The hepatic acinus includes two neighbouring hepatic lobules:
Zone 1: is closest to the ________ containing blood vessels and bile duct - cells here are last to die and first to regenerate if circulation is impaired
Zone 2: cells here show intermediate structural and functional characteristics
Zone 3: is furthest away from _______ - last to show effects of bile obstruction, first to show effects of fat accumulation
The hepatic acinus includes two neighbouring hepatic lobules:
Zone 1: is closest to the portal triad containing blood vessels and bile duct - cells here are last to die and first to regenerate if circulation is impaired
Zone 2: cells here show intermediate structural and functional characteristics
Zone 3: is furthest away from the portal triad - last to show effects of bile obstruction, first to show effects of fat accumulation
The small intestine extends from the _____ to the _____ and consists of three regions:
- _______
- _______
- _______-meets the large intestine at the ileocecal sphincter (valve)
The small intestine extends from the pyloric sphincter to the large intestine and consists of three regions:
- Duodenum
- Jejunum
- Ileum-meets the large intestine at the ileocecal sphincter (valve)
The small intestine receives blood from the _______ artery and ________ artery and then this blood drains into the ______ vein
The small intestine receives blood from the superior mesenteric artery and gastroduodenal artery and then this blood drains into the superior mesenteric vein
Remember, the GI tract has 4 major layers. In the small intestine, these layers are modified to ensure optimal digestion and absorption:
- Mucosa - has numerous ______ to increase surface area
- Submucosa - together with the mucosa forms the _______
- Muscularis - has _____ muscle
- Serosa - visceral peritoneum that surrounds ll except the majority of the ______
Remember, the GI tract has 4 major layers. In the small intestine, these layers are modified to ensure optimal digestion and absorption:
- Mucosa - has numerous villi to increase surface area
- Submucosa - together with the mucosa forms the circular folds
- Muscularis - has smooth muscle
- Serosa - visceral peritoneum that surrounds all except the majority of the majority of the duodenum
The mucosa of the small intestine is composed of ______, _______ and ______
- Specialized cells line the epithelium –
- _______cell,
- _______cell,
- _______ cell and
- _______ cell
- _______ cells line intestinal glands (crypts of Lieberkuhn)
- Lamina propria contains ______
The mucosa of the small intestine is composed of epithelium, lamina propria and muscularis mucosae
- Specialized cells line the epithelium –
- Absorptive cell,
- Goblet cell,
- Enteroendocrine cell and
- Paneth cell
- Secretly cells line intestinal glands (crypts of Lieberkuhn)
- Lamina propria contains MALT
The Submucosa of the small intestine is composed of Connective tissue containing _____ and _____ vessels and _____
- At the duodenum, _______\_glands secrete _____\_ to neutralize gastric acid in chyme
The Submucosa of the small intestine is composed of Connective tissue containing blood and lymphatic vessels and nerves
- At the duodenum, duodenal (Brunner’s) glands secrete alkaline mucus to neutralize gastric acid in chyme
The muscularis of the small intestine is composed of an outer thinner layer of _______ muscle and an inner thicker layer of _______ muscle
The muscularis of the small intestine is composed of an outer thinner layer of longitudinal smooth muscle and an inner thicker layer of circular smooth muscle
The serosa of the small intestine is composed of ________ that completely covers the small intestine with the exception of the majority of the _______
The serosa of the small intestine is composed of visceral peritoneum that completely covers the small intestine with the exception of the majority of the duodenum
The large intestine extends from the ____ of the small intestine to the _____
The large intestine extends from the ____ of the small intestine to the _____
The ascending and descending colon are ________
The ascending and descending colon are retroperitoneal
Colon structures (excluding the ascending and descending colon) are attached to the posterior abdominal wall by _______ which is a double layer of ______ connecting the _______ peritoneum to the _____ peritoneum
Colon structures (excluding the ascending and descending colon) are attached to the posterior abdominal wall by mesocolon which is a double layer of peritoneum connecting the parietal peritoneum to the visceral peritoneum
What are the four principal regions of the large intestine?
- ______
- ______
- ______
- ______
- Cecum
- Colon
- Rectum
- Anal Canal
The ____ is the blind pouch in the lower right of the abdominal cavity;
Chyme from the ileum passes through the _______ sphincter
The appendix contains _______ and is attached to the ileum by the _______
The Cecum is the blind pouch in the lower right of the abdominal cavity;
Chyme from the ileum passes through the ileocecal sphincter
The appendix contains lymphatic nodules and is attached to the ileum by the mesoappendix
The colon consists 4 segments:
- ______\_
- ______\_
- ______\_
- ______\_
-
_____\_ are condensed longitudinal muscle
- Runs the length of the colon
- Cause bunching of pouch-like structures (_____\_)
- _____\_ are small fat-filled pouches of visceral peritoneum that lines the teniae coli
The colon consists 4 segments:
- Ascending colon
- Transverse colon
- Descending colon
- Sigmoid colon
-
Teniae coli are condensed longitudinal muscle
- Runs the length of the colon
- Cause bunching of pouch-like structures (Haustra)
- Omental appendices are small fat-filled pouches of visceral peritoneum that lines the teniae coli
The _____ of the large intestine is located anterior to the sacrum and coccyx
Rectum
The ____ is the last 2-3cm of the large intestine
- Has mucous membrane arranged in longitudinal folds (_______) that contain blood vessels
The anal canal is the last 2-3cm of the large intestine
- Has mucous membrane arranged in longitudinal folds (anal columns) that contain blood vessels
The large intestine contains the same 4 layers of the GI tract but with functional differences:
- Mucosa - simple columnar epithelium, lamina propria, muscularis mucosa
- Absorptive cells ______ and goblet cells secrete _____
- No _____ secreted
- Submucosa - areolar CT
- Contains ___ and ____ vessels and nerves
- Muscularis - 2 layers of smooth muscle tissue
- inner circular layer
- outer longitudinal layer with 3 thickened bands ______
- Topic contractions create a series of pouches in the colon (_____)
- Serosa - Visceral peritoneum
The large intestine contains the same 4 layers of the GI tract but with functional differences:
- Mucosa - simple columnar epithelium, lamina propria, muscularis mucosa
- Absorptive cells reabsorb water and goblet cells secrete mucus
- No enzymes secreted
- Submucosa - areolar CT
- Contains blood and lymphatic vessels and nerves
- Muscularis - 2 layers of smooth muscle tissue
- inner circular layer
- outer longitudinal layer with 3 thickened bands teniae coli
- Topic contractions create a series of pouches in the colon (haustra)
- Serosa - Visceral peritoneum
