Flashcards in Abdomen Anatomy and Histology Deck (30):
What are flat muscles?
They are muscle required for flexion, lateral flexion and rotation that help compress the abdominal cavity.
They have fibres running in different directions to improve the strength of the abdominal wall
Which muscles in the abdomen are 'flat muscles'?
Transverse abdominus (deepest layer)
Internal oblique (intermediate layer)
External oblique (superficial layer)
What are vertical muscles?
These are the muscles responsible for a 'six pack'
They stabilise the pelvis when walking and depress the ribs.
Which muscles of the abdomen are 'vertical muscles'?
Rectus abdominus (superficial layer)
Pyramidalis (deep layer)
What are the four layer of the abdominal wall? (External to internal)
Muscle and associate fascia
What are the four main layers found in the GI tract?
What are the layers found within the mucosal layer?
(same lame muscles)
What layer are found within the he muscular propria (a.k.a the Muscularis externa)?
-Inner circular muscle
- Outer longitudinal muscle
N.B in the stomach there is an extra middle oblique muscle layer
Where are the plexus' found in the GI wall?
The submuscosal plexus is found between the mucosa and the submuscosa
The myenteric plexus is found between the inner and outer muscle layers in the muscularis externa
What is the function of protective mucosa in the GI tract and where is it found?
It has a protective function by reducing the friction as food passes along it.
It is found in the anal canal and oesophagus.
It is non-keratinised stratified squamous epithelium
What is the function of absorptive mucosa in the GI tract and where is it found?
This absorbs nutrients and is made up of simple columnar epithelium.
This is found throughout the small and large intestine
Describe the epithelial;I'm found specifically in the small intestine.
Simple columnar epithelium lines the long, finer-like villi projections.
The villi are separated by short glands (intestinal crypts) known as the crypts of leiberkuhn
The epithelium is renewed every four to five days, due to the proliferating stem cells found in the intestinal crypts
What is the function of secretory mucosa in the GI tract and where is it found?
This mucosa secretes mucous to protect the epithelium from stomach acid.
- some cells also secrete acid and other enzymes to aid digestion
This is only found in the stomach
It has simple columnar epithelium arranged in long tubular glands, arranged closely together
Where is the epiplopic foramen?
It is through the lesser omentum - and is the communication between the greater and lesser sacs of the abdomen.
The duodenum passes through this
What is the arterial supply to the oesophagus?
Upper third - inferior thyroid artery
Middle third - aortic branches
Lower third - left gastric artery
What is the venous drainage of the oesophagus?
Upper third - Inferior thyroid vein
Middle third - Azygos branches
Lower third - Left gastric vein
What is the lymph drainage of the oesophagus?
Upper third - deep cervical lymph nodes
Middle third - mediastinal lymph nodes
Lower third - gastric lymph nodes
Where does the oesophagus start?
At the cricoid cartilage, posterior to the trachea
How far does the abdominal oesophagus extend, and where does it begin?
It starts at the diaphragm, and extends for 3cm before connecting to the stomach
Where does swallowed air gather in the stomach?
Where is the angular notch?
At the base of the lesser curvature of the stomach
What does the pylorus area of the stomach mostly produce?
What parts of the GI tract does the coeliac trunk supply?
The stomach and other parts of the foregut
- greater omentum
What are the three major branches of the abdominal aorta?
Coeliac (1st branch - foregut)
Superior mesenteric (2nd branch - midgut)
Inferior mesenteric (3rd branch - hindgut)
What is the greater omentum?
A large fold of peritoneum that hangs free over the small intestine
It can help arrest inflammation and infection
What is the peritoneal cavity?
It's the cavity found between the parietal and visceral layer of the peritoneum
What is the infrasonic compartment?
A compartment beneath the large intestine that contains the small intestine
What are parabolic gutters?
They are spaces between the colon and the abdominal wall that allow the drainage/removal of infected fluid
They lead to the hepatorenal pouch
What is the lesser sac?
The fold of peritoneum that lies behind the stomach