Anatomy Week 3 Flashcards
Peritoneum:
A large, serous membrane that lines the abdominal cavity.
Describe the structure of the peritoneum:
A single layer of simple, squamous epithelium (mesothelium)
How is the peritoneum divided?
Parietal Peritoneum: Lines the body wall anteriorly and posteriorly.
Visceral Peritoneum: Surrounds and supports abdominal organs.
Intra-peritoneal vs Retro-peritoneal:
- Intra-peritoneal: Organs that are completely surrounded by peritoneum (and mesentery) and suspended in abdominal body wall.
- Retro-peritoneal: Organs that are attached to the posterior body wall and not completely surrounded by mesentery.
List the 5 major peritoneal folds:
- Greater Omentum
- Falciform Ligament
- Lesser Omentum
- Mesentery
- Mesocolon (Transverse and Sigmoid)
What is unique about the falciform ligament?
It attaches the liver to the VENTRAL body wall. The rest attach organs to the posterior abdominal wall (retro-peritoneal structures).
What is another name for the Greater Omentum?
The policeman of the abdomen: Because it is freely moving, it can migrate to cover any inflamed/infected regions of the abdomen to protect them from spreading to the rest of abdomen.
2 Components of the Lesser Omentum:
- Hepato-Duodenal Ligament
2. Hepato-Gastric Ligament
What is the Omental Foramen?
An opening into the lesser omental sac, which can accumulate fluid.
What is the “root” of the mesentery?
The attachment of the mesentery to the posterior wall.
2 Components of the Mesocolon:
- Transverse Mesocolon: Attaches transvere colon to posterior wall.
- Sigmoid Mesocolon: Attaches sigmoid colon to posterior wall.
Peritoneal Cavity:
The space between the parietal and visceral peritoneum.
Peritonitis:
Inflammation of the peritoneal membrane, most commonly due to infection resulting from an injury that punctures the abdominal or abdominal organs.
What is another name for the GI Tract?
The Alimentary Canal
Esophagus to Anal Canal
4 layers of GI Tract:
- Mucosa
- SubMucosa
- Muscularis Externa
- Serosa
Peristalsis:
The simultaneous constriction of the GI tube by Circular muscle and shortening of the tube by Longitudinal muscle to push and propel contents forward.
The serosa is the mesothelium that is continuous with _______, and it is a ______ membrane.
- The Mesentery
2. Serous
Serosa vs Adventitia:
Adventitia is LOOSE connective tissue that attaches parts of the GI tract without a serosa layer to the body wall.
Name the 4 structures that possess an Adventitia Layer:
- Thoracic Esophagus
- 2nd, 3rd, and 4th parts of duodenum
- Asc./Desc. Colon
- Rectum/Anal Canal
Esophagus:
Muscular tube that connects:
Pharnyx –> Stomach
The first cartilaginous structure of the larynx is the _______, which is also called the _______. It is followed by the _______.
- Thyroid Cartilage “Adam’s Apple”
2. Cricoid Cartilage
The Cricoid cartilage is followed by the _______ which forms part of the ______.
- Crico-pharyngeal Muscle
2. Esophageal Sphincter
What is seen at the point where the trachea splits off into the 2 main bronchi?
The Aorto-bronchial constriction
Esophageal Hiatus:
Opening of the diaphragm that the esophagus passes through to reach the stomach.
Pyrosis:
Heartburn caused by acid reflux into the esophagus from the stomach.
If pyrosis progresses, it can become _______. If THIS progresses, it can become _______, which is _______.
- GERD
2. Barrett’s Esophagus: Metaplasia of cells
Esophagogastric Junction:
The abrupt change in lining of the esophagus epithelium when it becomes the stomach epithelium.
(Strat. Squam. –> Simple Columnar)
What is the FUNCTIONAL difference in epithelium that occurs at the esophagogastric junction?
The “protective” epithelium of the esophagus transitions into more “secretory” epithelium in the stomach.
Barrett’s Esophagus:
Stratified squamous epithelium of the lower esophagus becomes simple columnar epithelium due to constant stimulus from the stomach.
Adenocarcinoma:
Malignant growth of GLANDULAR origin.
Description and Function of Rugae:
- Longitudinal Folds of the mucosa and submucosa inside the stomach.
- Allow distension/relaxation of the stomach.
Main function of stomach:
Secretion of HCl and gastric enzymes to begin digestion and mix contents.
(i.e. Bolus –> Chyme)
3 Layers Of Stomach Musc. Externa:
- Internal Oblique
- Middle Circular
- Outer Longitudinal
What regulates the flow of chyme from the stomach to the duodenum of the small intestine:
The Pyloric Sphincter
What peritoneal structure hangs below the stomach?
The Greater Omentum
What 2 structures lie to the anatomical left of the stomach:
- The Spleen
2. The Left Colic Flexure (as the transverse colon becomes the descending colon)
Give the 5 cell types of Gastric glands and their secretion:
- Surface Mucous Cell: Mucous
- Neck Mucous Cell: Mucous
- Parietal Cell: HCl and Intrinsic Factor
- Chief Cell: Pepsinogen + Gastric Lipase
- G-Cell: Gastrin
What other cell type is found in the neck of the gastric gland besides neck mucous cells?
Stem cells for rapid turnover of epithelium
What is Pernicious Anemia?
A disease resulting from lack of Vitamin B12 absorption due to lack of Intrinsic Factor.
Gastrin Functions: (2)
- Activate Parietal cells to secrete HCl and Intrinsic Factor
- Stimulate Gastric Motility (mixing via contraction)
Function of HCl in stomach:
Convert Pepsinogen –> Pepsin
What are Enteroendocrine cells? Give an example:
Hormone producing cells of the enteric system.
Ex: G-Cells in stomach produce Gastrin which travels through the blood to distant targets to elicit an effect.
Ulcer:
An erosion of the mucosa of the GI tract wall.
Chronic Peptic Ulcer:
An ulcer that has degraded the mucosa, submucosa, and part of the muscularis externa.
Perforation:
Complete opening into peritoneal cavity
releasing stomach contents into peritoneum can cause infection/inflammation
Hemorrhage:
Tissue necrosis of peptic ulcer and stomach contents leaking reaches large arteries and causes bleeding.
Obstruction:
Fibrous scarring builds up from repeated attempts at repairing necrosis, causing narrowing or complete blockage of the lumen.