Digestive system Flashcards
List the five layers of the digestive tract
- Mucosa (inner layer) mucus producing cells
- Submucosal layer
- Circular smooth muscle fibers
- Longitudinal smooth muscle fibers
- The outer layer of the wall comprises the visceral peritoneum or serosa
peritoneum
large serous membrane in the abdominal cavity
The _______________ covers the abdominal wall and the superior surface of the urinary bladder and uterus and then continues to form the __________________
parietal peritoneum
visceral peritoneum
Purpose of the mesentery
The mesentery supports the intestines and conveys blood vessels and nerves to supply the wall of the intestines
greater omentum
The greater omentum is a layer of fatty peritoneum that hangs from the stomach like an apron over the anterior surface of the intestines
lesser omentum
The lesser omentum is part of the peritoneum that suspends the stomach and duodenum from the liver
what happens when inflammation develops in the intestinal wall,
the greater omentum, with its many lymph nodes , tend to adhere to the site , walling off the inflammation and temporarily localizing the source of the problem
Inflammation of the omentum and peritoneum may lead to ___________ and the formation of ________ between structures in the abdominal cavity which may lead to obstruction
scar tissue
adhesions
The _______________ are located posterior to the stomach against the abdominal wall and behind the parietal peritoneum
kidneys and pancreas
What is unique about the kidneys and pancreas which makes them retroperitoneal organs
They are covered with peritoneum only on the anterior surface and are therefore referred to as retroperitoneal organs
Where does saliva come from?
from parotid, sublingual and submandibular glands
amylase
enzyme from saliva which begins the digestion of CHO
When food is ready to be swallowed, the tongue pushes the Bolus or ball of food back into the pharyngeal wall. Receptors of the __________________________ nerves relay the information to the swallowing center in the medulla
trigeminal and glossopharyngeal
describe the sequence of events in the swallowing reflex
- The soft palate is pulled upward –
- The vocal cords are approximated –
- The epiglottis covers the larynx –
- Respiration ceases –
- The bolus is seized by the constricted pharynx –
- As the bolus of food moves into the esophagus, distending the wall, peristalsis is activated pushing the food down –
- The lower esophageal sphincter relaxes allowing it to drop into the stomach
what normally prevents reflux of gastric contents
The pressure in the sphincter normally prevents reflux of gastric contents back up the esophagus
parietal cells that secrete
HCl
chief cells that secrete
pepsinogen (converted to pepsin by HCl)
Secretions from the liver and pancreas are added to the chyme, where?
duodenum
glycogenolysis
Glycogen to glucose
gluconeogenesis
Converts protein and fat to glucose