contents of the abdomen Flashcards
what are the 6 processes involved in the digestive system?
- ingestion
- secretion of digestive fluids
- mixing and propulsion
- digestion
- absorption
- defecation
what is the serous layer?
- outer membrane
- encloses several body cavities
- secrete a lubricating fluid
- outer epithelial layer (secretory) and inner layer (connective tissue with layers)
what is the muscular layer?
- longitudinal or circular
- responsible for movement of lumen contents
what is the mucosal layer?
- inner layer
- lines internal organs or cavities exposed to external environment
- secrete mucus
- involved in absorption
what are the GI tract divisions?
- oral cavity
- pharynx
- oesophagus
- diaphragm
- stomach
- small intestine (duodenum, jejunum, ileum)
- large intestine (colon)
what is the function of the teeth?
- accessory organs
- assist mechanical digestion
what is the function of the palate?
- roof of mouth
- soft palate blocks nasal cavity during swallowing
what is the function of the tongue?
- accessory organ
- taste
- assist mixing
- swallowing
what is the function of the salivary glands?
secretion of saliva
what is the function of the pharynx?
- directs food to oesophagus
- blocks entry to trachea
what are the key characteristics of the oesophagus?
- muscular tube around 25cm long
- posterior to trachea
- upper edge: pharynx
- pierces of diaphragm
- opens to stomach
what are the key characteristics of stomach anatomy?
- most dilated part of alimentary canal
- between oesophagus and small intestine
- J shaped; lies under diaphragm and under heart
- 2 openings, curvatures, surfaces
- mechanical and chemical digestion
- lesser and greater curvatures
- pyloric and cardiac sphincters
what does the cardiac orifice link the stomach to?
links stomach to oesophagus
what does the pyloric orifice link the stomach to?
links stomach to small intestine
what are the 3 layers of muscle in the stomach?
- longitudinal
- circular
- oblique
what are the 3 divisions of the small intestine?
- duodenum
- jejunum
- ileum
what are the key characteristics of the small intestine?
- convoluted tube
- pylorus of stomach to ileocaecal junction
- 5 metres in length
- where digestions and absorption take place
what are the key characteristics of the duodenum?
- around 20-25cm
- retroperitoneal
- C shaped
- where the duct from the pancreas and gall bladder open
- ends at the duodenal: jejunal flexure
what are the 4 parts of the duodenum?
- superior
- descending
- horizontal
- ascending
what are the key characteristics for the jejunum/ileum?
- fasting (empty in death)
- at least 3cm long from duodenal - jejunal flexure to ileocaecal junction
- site of absorption: large surface area, further increased by circular folds, villi and microvilli, motility
- motility: one attached and one free edge
what are the key characteristics of the large intestine?
- terminal division of the GI tract: from end ilium to anus
- 1.5m length: cross section compared to small
- ascending/descending parts are retroperitoneal
- absorption of water, from faeces and expelling these (defecating)
- rectum/anus: sphincters close outside world except when defecating
what are the 4 parts (right to left) of the large intestine?
- ascending
- transverse
- descending
- sigmoid
what are the branches of the superior mesenteric?
- distal part of duodenum to proximal 2/3 transverse colon
- jejunal and ill branches
- middle colic
- right colic
- ileocaecal
what are the branches of the inferior mesenteric?
- distal 1/3 transverse colon to half way down anal canal
- left colic
- sigmoid
- superior rectal
what are the gut associated glands?
- liver
- spleen
- gall bladder
- pancreas
