1 INTRO Flashcards
Where does the esophagus enter the diaphragm?
T10
Where does the Esophagus end?
At cardia of the stomach, T11
The esophagus passes close to ______
The trachea and left side of heart
Can problems with the esophagus cause problems with the heart?
YES - Eating something too hot can sometimes feel like pain close to or in the heart or throat
The esophagus is surrounded at the top and bottom by 2 muscular rings, what are they?
The upper esophageal sphincter and lower
What lines the esophagus ?
Has a nonkeratinized stratified squamous epithelial lining which protects the esophagus from trauma
What does the submucosa of the esophagus secrete?
Mucus from mucous glands which aids the passage of food down the esophagus
What is the lumen of the esophagus surrounded by?
Layers of muscle
The lumen of the esophagus has muscles, what types of muscles are in these?
- Voluntary in TOP 1/3rd (striated) - Involuntary in the BOTTOM 1/3rd (smooth muscle) - The MIDDLE 1/3rd containing a mixture of BOTH
What shape is the stomach?
J-Shaped with 2 openings 1). Esophageal 2). Duodenal
What are the 4 major regions of the stomach?
Fundus, Cardia, Stomach Body, Pylorus
What does the fundus collect?
Digestive gases
What does the body of the stomach secrete?
Pepsinogen and Hydrochloric acid
The pylorus is responsible for _____
Production of mucus, hormone gastrin, and pepsinogen secretion
The glandular tissue within the stomach mucosa account for secretion of various substances, what are they?
1). Parietal cells 2). Chief (zymogen) cells 3). Enteroendocrine cells (G cells)
What do parietal cells secrete?
Hydrochloric acid and intrinsic factor
What do chief (zymogen) cells secrete?
Pepsinogen
What do enteroendocrine cells (G-cells) secrete?
Hormone gastrin
The stomach wall contains 3 layers of involuntary smooth muscles which aid digestion by physically breaking up the food particles, what are they?
- Inner oblique layer 2. Circular layer 3. Outer longitudinal layer
What are the 5 major functions of the stomach?
- Preliminary digestion of protein with pepsin 2. Temporary food storage 3. Control of the rate at which food enters the duodenum 4. Acid secretion and antibacterial action 5. Fluidsation of stomach content
What are the 3 main sections of the small intestine?
- Duodenum 2. Jejunum 3. Ileum
The small intestine is the site where the most of _____ is carried out?
Chemical and mechanical digestion and where virtually all of the absorption of useful material is carried out
What is the wall of the small intestine lined with?
An absorptive type of mucosa, with certain modifications of each intestine
What does the wall of the small intestine have as far as muscles?
2 layers of smooth muscles, rhythmical contractions of which move products of digestion through the intestine (peristalsis)
The duodenum is the _____
FIRST of 3 parts of the intestine
What is the duodenum attached to?
The pylorus of the stomach
How long is the Duodenum?
25-30 cm long (12 fingers length), C - Shaped, and is located in upper abdomen
What lies in the C shape of the duodenum?
Pancreas
What are the 4 subdivisions of the duodenum?
- Superior part 2. Descending part 3. Horizontal part 4. Ascending part
Where does the superior part of the duodenum lie?
It lies intraperitoneally and is enlarged proximally (duodenal bulb)
The descending part and the rest of the duodenum is ______
Retroperitoneally
How do the pancreatic duct and common bile duct enter the descending duodenum through the _____
Major duodenal papilla - Hepatopancreatic ampulla (= ampulla of Vater)
The second part (descending) of the duodenum also can contain the _____
Minor duodenal papilla
What is the entrance for the accessory pancreatic duct?
The minor duodenal papilla (Papilla of Santorini)
Where does the Horizontal part of the duodenum pass?
In front of the inferior vena cava, abdominal aorta and the vertebral column, runs from right to left.
Where does the horizontal duodenum locate?
Retroperitoneally
How does the Ascending part of the Duodenum run?
Cranially along the left side of the vertebral column
What is special about the ascending part of the duodenum?
It joins with the jejunum
Where is the ascending part of the duodenum located?
Retroperitoneally
What are the main functions of the duodenum?
- neutralizing of acidic gastric content - further digestion - absorption of nutrients - regulation of the rate of gastric emptying
How does the duodenum neutralize acidic gastric content?
Brunner’s glands
Where are Brunner’s glands?
They are found in the duodenum only, locate in its submucosa.
What do Brunner’s glands secrete?
An alkaline mucus which neutralizes the chyme and protects the surface of the duodenum
What are the jejunum and ileum?
The greatly coiled parts of the small intestine, and together are about 4-6 meters long
What is special about the mucosa of the jejunum and ileum?
It is highly folded (folds are called plicae) and increase surface area for absorption