Contents of the abdomen Flashcards
Abdominal subdivisions
The upper region:
Right hypochondriac
Epigastric
Left hypochondriac
Middle region:
Right lumbar
Umbilical
Left lumbar
Lower region:
Right iliac/ inguinal
Hypogastric/ pubic
Left iliac
Organs in the right upper region of the abdomen
Right lobe of the liver
Gallbladder
Duodenum
Head of pancreas
Hepatic flexure of colon
Part of the ascending and transverse colon
Organs in the left upper region of the abdomen
Stomach
Spleen
Left lobe of the liver
Body of pancreas
Splenic flexure of colon
Part of the transverse and descending colon
Organs in the right lower region of the abdomen
Cecum
Appendix
Ascending colon
Small intestine
Organs in the left lower region of the abdomen
Small intestine
Descending colon
Sigmoid colon
Three layers of the digestive tract
Serous- outer membrane
Muscular- middle layer
Mucosal- inner layer
Serous layer
Outer membrane of the digestive tract.
Secretes lubricating fluid
The outer epithelial layer secretes substances whilst the inner layer contains connective tissues and vessels.
Muscular layer
The middle layer of the digestive tract.
Can be longitudinal or circular
Responsible for moving the contents of the lumen.
Mucosal layer
The innermost layer of the digestive tract
Lines internal organs exposed to the external environment.
Secretes mucus (duh)
GI tract division
Oral cavity —> Pharynx —> Oesophagus —> Stomach —> Duodenum —> Jejunum —-> Ileum —> Colon—> anus
Oral cavity
Point of entry in the GI tract.
Contains accessory organs:
Teeth- mechanical digestion
Tongue- taste, swallowing, mixing
Palate- blocks nasal cavity during swallowing
Salivary glands
Pharynx
Area of the GI tract after the oral cavity.
Directs food to the oesophagus from the mouth.
Oesophagus
After the pharynx
Around 25 cm
Posterior to trachea
Pierces diaphragm at T10, at the oesophageal hiatus—-> Leads to the stomach
Stomach
- Location
- Openings
- Curvatures
- Sphincters
- Muscle layers
Most dilated part of the alimentary canal, between the oesophagus and small intestine.
Under the heart and diaphragm.
Openings:
Cardiac orifice- from oesophagus
Pyloric orifice- to the duodenum
Curvatures:
Lesser- superior
Greater- inferior
Sphincters:
Pyloric
Cardial
Muscular layers:
Longitudinal
Circular
Oblique
Small intestines
- Function
- Length
- Sections
Convoluted tube that connects the Pylorus of the stomach to the ileocaecal junction.
Area for digestion and absorption of food.
5m long
Sections:
- Duodenum
- Jejunum
- Ileum
Duodenum
- Structure
- Parts
- Function
- Ending
The first section of the small intestines:
Connects pylorus to the jejunum.
Retroperitoneal
C shape, Parts: Superior Descending Horizontal Ascending
The duct from the pancreas and gallbladder release their juices into the duodenum.
Ending: duodenal-jejunal flexure
Jejunum and Ileum
The site of absorption of the small intestines.
Contains villi and microvilli which increase SA for absorption.
Contains one attached and one free edge to allow motility.
Colon
Joins ileum to the anus- terminal section of the GI tract.
M shaped, 4 parts: Ascending- retroperitoneal Transverse Descending- retroperitoneal Sigmoid
Function:
Absorption of water
Formation and defecation of faeces
Rectum and anus- contains sphincter that allows defecation
Foregut
- Blood supply and drainage
- Lymphatics
- Nervous supply
Artery
- Celiac
Vein
- Portal
Lymphatics
- Celiac nodes
Sympathetic supply = celiac ganglia
Parasympathetic supply= vagus
Midgut
- Blood supply and drainage
- Lymphatics
- Nervous supply
Artery
- Superior Mesenteric
Vein
- Superior mesenteric
Lymphatics
- Superior mesenteric nodes
Sympathetic supply = Superior mesenteric ganglia
Parasympathetic supply= vagus
Hindgut
- Blood supply and drainage
- Lymphatics
- Nervous supply
Artery
- Inferior Mesenteric
Vein
- Inferior mesenteric
Lymphatics
- Inferior mesenteric nodes
Sympathetic supply = Inferior mesenteric ganglia
Parasympathetic supply= Pelvic splanchnic
Superior mesenteric artery
Artery that supplies the midgut: Distal part of the duodenum to the proximal 2/3 of the transverse colon
Branches:
Middle colic
Right colic
Ileocaecal
Jejunal and ileal branches
Inferior mesenteric artery
Artery that supplies the hindgut: Distal 1/3 of the transverse colon and half way down anal canal
Branches (moving clockwise):
Left colic
Sigmoid
Superior rectal
Pelvic splanchnic nerves
Spinal nerves S2-4, sacral plexus
Parasympathetic supply to the hindgut.
