The Digestive System 1 Flashcards
Name the 4 Abdominal Quadrants
Right upper quadrant
Left upper quadrant
Right lower quadrant
Left lower quadrant
What do each Abdominal Quadrants consist of ?
Right upper quadrant
- liver, stomach, gall bladder, duodenum, right kidney, pancreas, transverse colon, small intestine and right adrenal gland
Left upper quadrant
- liver, left adrenal gland, stomach, left kidney, pancreas, spleen, transverse colon and small intestine
Right lower quadrant
- large intestine cecum, right ureter, appendix, right reproductive organs – ovary, fallopian tube, spermatic cord
Left lower quadrant
- left ureter, small intestine, large intestine, left reproductive organs – ovary, fallopian tube, spermatic cord
What are the 4 abdominal quadrants created by?
They are created by the a transverse plane which is also called the trans umbilical plane
The naval - belly button - is the main landmark to locate the four quadrants – the point where two planes intersect.
- right and left are from the person in anatomical position
Name the 9 abdominal regions
Left and right hypochondriac region
Epigastric region
Right and left lumbar region
Umbilical region
Right and left iliac region
Hypogastric region
H
E
L
U
I
H
what do the 9 abdominal regions consist of?
Left hypochondriac region
- livers tip, stomach, pancreas, left kidney, spleen, large/small intestine
Right hypochondriac region
– hypo means below, chondriac means cartilage of ribs – under the ribs
- liver, right kidney, gall bladder, large/small intestine
Right lumbar region
- ascending colon, small intestine and right kidney
Left lumbar region
- lumbar vertebrae in lower back, between ribs and pelvis
- descending colon, small intestine and left kidney
Right iliac region
- appendix, caecum, ascending colon, small intestine
Left iliac
- top of hip bone has iliac crest, this region is closest to hip bone
- sigmoid colon, descending colon and small intestine.
Hypogastric region
– hypo means below, gastric means stomach, below the stomach
- bladder, sigmoid colon, small intestine and reproductive organs
Umbilical region
– navel – umbilicus – middle
- duodenum, small intestine, transverse colon
Epigastric region
– above the stomach
- over, stomach, spleen, duodenum, adrenal glands and pancreas
Describe the structure of the abdominal wall
The first layer is the epidermis - skin - layer
The second layer is the subcutaneous layer - this can be split into 3 parts
- fatty layer to insulate us - superficial fascia layer
- membrane layer.- superficial membrane fascia
- deep adipose layer
We then have muscles such as external and internal oblique muscles
We then have an external peritoneal fascia layer
finally we have the parietal peritoneal layer
Describe the superior thoracic aperture
It is the opening of t1 just before the sternum where all the blood vessels enter and exit
Describe the inferior aperture
It is the lower aspect of the thoracic region. This is at t12, where the diaphragm pushes the ribs up separating the abdomen from the rib cage.
The abdomen begins at the inferior thoracic aperture
Describe the abdomen and pelvis relation
The abdomen freely communicates with the pelvis inferior to the pelvic inlet
Describe the peritoneal cavity in the abdomen
The peritoneal cavity is the space between the parietal and visceral linings. Now this space contains peritoneal fluid.
The fluid is divided
Describe the parietal peritoneal cavity and the visceral peritoneal cavity
The parietal peritoneal layer surrounds the lining of the abdominal cavity whilst the visceral lining surrounds the abdominal organs for example the liver, spleen and stomach ect. Both of these linings are the same layer going all the way around just different names that’s all.
Why do we need peritoneal fluid in the peritoneal cavity?
It helps with the movement and expansion of the gut by lubricating it.
Describe the greater omentum
Omentum is double folds of the visceral peritoneal lining
Greater omentum
Folds that connect intra peritoneal organs
Connects stomach, duodenum to other organs
- largest peritoneal fold
- Highly vascularised and fatty
- fro greater curvature of stomach
- passes over transverse colon and loops of small bowel
- Encloses spleen
What are mesenteries?
A messentry is when the double folds (omentum) attaches to the posterior abdominal wall.
A mesentery surrounds and supports loops of bowel. Double layers connected posteriorly to the abdominal wall and then ‘encase’ the loops of bowel.
Messentry is a double layer of parietal peritoneum on dorsal aspect of peritoneal cavity.
It provides routes for vessels, lymphatics, nerves to digestive organs.
Allows some movement of bowel
Three types
Messentry: loops of Jejunum and ileum
Transverse mesocolon
Sigmoid mesocolon
The small intestine has a double fold that attaches itself to the posterior end of the abdominal cavity. - this is a messentry
What are Intra Peritoneal organs
So we have intraperitoneal organs, these are organs that are almost surrounded by the visceral peritoneal lining like the stomach
Stomach
Gi tract including
Ilium
duodenum first part
Jejunum
Caecum
Appendix
Transverse colon
Sigmoid colon
1/3 rectum
there is a space between the parietal and visceral peritoneal lining that is called the peritoneal cavity - the fluid.
the visceral peritoneal lining is encapsulated in the peritoneal cavity.
What are Retro Peritoneal organs
The retroperitonal organs are those organs which are only surrounded by the parietal peritoneal lining
Kidneys
Adrenal glands
Ureters
Aorta
Inferior vena cava
2/3 rectum
What is the function of the abdomen?
The abdomen protects and contains major organ such as the stomach and intestines
The abdominal wall relaxes to allow the thoracic cavity to expand when we inhale and to contra t to reduce thoracic cavity for example whenever we sneeze or cough.
There is an increase in abdominal pressure to assist in childbirth.
What is mastication
The process in which the mouth chews food
What happens after mastication
The food goes down the oesophagus as a bolus
Where does the food go after the oesophagus
The food (bolus) goes into the stomach.
The stomach mixes hydrochloric acids to digest some of the food so it becomes mushy
When the food becomes mushy in the stomach where does it then go
The mushy food is known as chyme.
The chyme goes into the small intestine from the pylorus sphincter
The small intestine is the main site for absorption.
What is the gi tract also known as?
Alimentary canal
what are the four layer of the gi tract
Mucosa
Submucosa
Muscularis externa
Serosa / adventitia
Describe the mucosa in the alimentary tract
Inner most layer
Has 3 parts
Epithelial tissue - directly contacting the contents
In the mouth to upper oesophagus and anus, there is stratified squamous epithelium
In the stomach to rectum, there is simple columnar epithelium
Lamina propria - loose connective tissue
Muscularis mucosa - thin ring of smooth muscle
Describe the Submucosa in the alimentary canal
Thicker area of loose connective tissue
This is where the blood supply, nerve supply, nerve supply is distributed through the gi tract.
It also contains mucous glands
Describe the muscularis externa in the gi tract
There are two layers of smooth muscle
The inner layer is the circular coat that encircles the lumen
The outer layer is called the longitudinal coat
Describe the serosa / adventitia in the gi tract
This is the visceral peritoneum
It is a serous membrane
In the abdominal and pelvic cavity, it is called the serosa
Surrounding the oesophagus and distal rectum, it is called the adventitia
Describe the lesser omentum
Omentum is double folds of the visceral peritoneal lining
The lesser omentum is a peritoneal double fold
It is the smaller omentum
It origins from the lesser curvature of the stomach
It is connected to the inferior part of the liver through hepatogastric and hepatoduodenul ligaments
Anteriorly, It contains gastris and hepato arteries, portal veins and bile ducts
It forms the anterior border of the epiploic foramen
It is superior to the greater sac of peritoneal cavity
It is posterior to the stomach and liver
Where does the abdomen begin ?
It begins at the inferior thoracic aperture
What is the abdomen wall bounded by
It is bounded by xiphisternum and lower costal margins(superiorly), pelvic bone (inferiorly), spine (posteriorly.
What are the ligaments in the peritoneal cavity?
There are 2 layers of peritoneum connecting organs or organ to abdominal wall
Describe the falciform ligament
It attaches anterior part of liver to anterior abdominal wall
