Podcast
Questions and Answers
Which structure primarily regulates the passage of food residue from the ileum to the large intestine?
Which structure primarily regulates the passage of food residue from the ileum to the large intestine?
Which region of the small intestine is primarily intraperitoneal and highly vascularized?
Which region of the small intestine is primarily intraperitoneal and highly vascularized?
What is the primary blood supply to the stomach?
What is the primary blood supply to the stomach?
Which part of the liver is responsible for separating the left and right lobes?
Which part of the liver is responsible for separating the left and right lobes?
Signup and view all the answers
What structure begins at the pyloric valve and receives contents from the stomach?
What structure begins at the pyloric valve and receives contents from the stomach?
Signup and view all the answers
Which part of the large intestine is located inferior to the ileal papilla?
Which part of the large intestine is located inferior to the ileal papilla?
Signup and view all the answers
The ileocecal junction is specifically where which two structures meet?
The ileocecal junction is specifically where which two structures meet?
Signup and view all the answers
What is the primary function of the hepatic portal vein?
What is the primary function of the hepatic portal vein?
Signup and view all the answers
What is the name given to the mixture of food and saliva before it enters the stomach?
What is the name given to the mixture of food and saliva before it enters the stomach?
Signup and view all the answers
Which section of the small intestine primarily absorbs nutrients?
Which section of the small intestine primarily absorbs nutrients?
Signup and view all the answers
Which part of the digestive system prevents the regurgitation of food back into the esophagus?
Which part of the digestive system prevents the regurgitation of food back into the esophagus?
Signup and view all the answers
Where does the gallbladder lie in relation to the liver?
Where does the gallbladder lie in relation to the liver?
Signup and view all the answers
What regulates the passage of material out of the anus?
What regulates the passage of material out of the anus?
Signup and view all the answers
What type of tissue primarily makes up the mucosa layer of the digestive tract?
What type of tissue primarily makes up the mucosa layer of the digestive tract?
Signup and view all the answers
Which of these regions of the large intestine has three curves and three infoldings?
Which of these regions of the large intestine has three curves and three infoldings?
Signup and view all the answers
Which of the following is NOT considered an accessory organ of digestion?
Which of the following is NOT considered an accessory organ of digestion?
Signup and view all the answers
What is the length of the small intestine in a living person?
What is the length of the small intestine in a living person?
Signup and view all the answers
What is the primary function of the submucosa in the digestive tract?
What is the primary function of the submucosa in the digestive tract?
Signup and view all the answers
What is the approximate weight of the liver in a healthy adult?
What is the approximate weight of the liver in a healthy adult?
Signup and view all the answers
In which abdominal region is the stomach primarily located?
In which abdominal region is the stomach primarily located?
Signup and view all the answers
Which salivary gland is responsible for producing the greatest percentage of saliva?
Which salivary gland is responsible for producing the greatest percentage of saliva?
Signup and view all the answers
Which of the following structures is considered a component of the gastrointestinal tract?
Which of the following structures is considered a component of the gastrointestinal tract?
Signup and view all the answers
What structure transforms the bolus into chyme?
What structure transforms the bolus into chyme?
Signup and view all the answers
What is the name of the tissue layer that creates grooves to enhance surface area in the digestive tract?
What is the name of the tissue layer that creates grooves to enhance surface area in the digestive tract?
Signup and view all the answers
Study Notes
Digestive System Overview
- The digestive system's function is ingestion, transport, breakdown of food, absorption of nutrients, and expulsion of wastes.
- Food mixed with saliva is called a bolus.
- The stomach converts bolus into chyme.
- The esophagus transports food to the stomach.
- The liver detoxifies molecules, stores vitamins/iron/glycogen, and creates bile.
- The gallbladder stores and concentrates bile.
- The pancreas releases digestive enzymes and hormones (e.g., insulin).
- The small intestine absorbs nutrients.
- The rectum/anus stores and expels feces.
- The large intestine absorbs water and ions.
Structure of the Digestive System
- The gastrointestinal (GI) tract includes the oral cavity, pharynx, esophagus, stomach, small intestine, and anus.
- Accessory digestive organs are the teeth, tongue, salivary glands, liver, gallbladder, and pancreas.
Anatomy of the Oral Cavity and Esophagus
- The oral cavity has a vestibule between the cheeks/lips and gums and an oral cavity proper central to the alveolar processes of the jaw bones.
- Structures within the oral cavity: teeth, tongue, vestibular, palatoglossal arch, palatopharyngeal arch, palatine tonsil, lingual frenulum, salivary ducts, sublingual, and submandibular glands.
- The esophagus connects the pharynx to the stomach, is a muscular tube (25-30 cm long), begins at C6 and cricoid cartilage, and extends to the cardiac orifice of the stomach.
Anatomy of the Stomach
- The stomach is located in the upper left quadrant and in the epigastric and left hypochondriac regions.
- The stomach has four regions: cardia, fundus, body, and pylorus.
- The internal surface of the stomach has gastric folds (rugae).
- The pylorus is the funnel-shaped terminal region.
- The lesser curvature and greater curvature are distinct regions of the stomach.
Innervation and Circulation of the Stomach
- The stomach is innervated by parasympathetic fibers from the vagus nerve and sympathetic fibers from the celiac ganglia.
- Branches of the celiac trunk supply blood to the stomach.
- Blood drained from the stomach and intestines enters the hepatic portal circulation and is filtered through the liver before returning to the heart.
Small Intestine
- The small intestine is the longest part of the GI tract (about 5 m in a living person; up to 8 m in a cadaver).
- It has a diameter of about 2.5 cm.
- The small intestine is subdivided into the duodenum, jejunum, and ileum.
- The duodenum begins at the pyloric valve, receives stomach contents, pancreatic juice, and bile.
- The duodenojejunal flexure marks the border between the duodenum and jejunum.
- The jejunum is intraperitoneal, has a rich blood supply (which gives it a red color).
- The ileum is intraperitoneal; the ileocecal junction is where the ileum joins the cecum of the large intestine.
- The ileal papilla protrudes into the cecum, and controls the passage of food residue into the large intestine.
Large Intestine
- The large intestine begins as the cecum inferior to the ileal papilla.
- The colonic regions include ascending, transverse, and descending colon and portions between them like right and left colic flexures, and the sigmoid colon.
- The rectum has three curves and folds, called transverse rectal folds/rectal valves..
- The anal canal is the final 3 cm of the large intestine; passes through the levator ani muscle and pelvic floor, and terminates at the anus.
- The internal and external anal sphincters are located at the end of the anal canal.
Liver
- The liver is a reddish brown organ located immediately inferior to the diaphragm, in the right upper abdominal quadrant.
- It is the body's largest organ (~1.4 kg (3 lbs)).
- The liver performs various functions, including detoxification, production of cholesterol and hormones like vitamin D, metabolism, storage of micronutrients, and immune response.
- The liver produces bile.
- The liver is divided into four lobes (Right, Left, Quadrate and Caudate lobes).
- The liver has ligaments, including the falciform ligament, which separates left and right lobes.
- The round ligament (ligamentum teres) is a fibrous remnant of the umbilical vein.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
