M104 T1 L3 Flashcards
What are the four different quadrants the abdomen is split into?
rU, rL, lU, lL
right upper quadrant
right lower quadrant
left upper quadrant
left lower quadrant
What are the quadrants in the first / upper row of the nine different quadrants the abdomen is split into?
right hypochondriac region
epigastric region
left hypochondriac region
What are the four different quadrants used for?
to identify where pain is bc it is more general and hard to pinpoint, so using 9 quadrants wouldn’t be more useful
When are the nine different quadrants used?
when being specific
when looking at the organs in a particular area
What are the quadrants in the second / middle row of the nine different quadrants the abdomen is split into?
right lumbar region
umbilical region
left lumbar region
What are the quadrants in the third / lower row of the nine different quadrants the abdomen is split into?
right inguinal (iliac) region hypogastric (pubic) region left inguinal (iliac) region
Where is the transpyloric plane?
it goes through the pylorus
it is around the level of L1
What are the contents of the right upper quadrant?
Right lobe of liver Gallbladder Duodenum Head of Pancreas Hepatic flexure of colon Part of the ascending colon Part of the transverse colon
What are the contents of the right lower quadrant?
Cecum
Appendix
Ascending colon
Small intestine
What are the contents of the left upper quadrant?
Stomach Spleen Left lobe of liver Body of pancreas Splenic flexure of colon Part of the transverse colon Part of the descending colon
What are the contents of the left lower quadrant?
Small intestine
Descending colon
Sigmoid Colon
What are the processes of the digestive system?
Ingestion Secretion of digestive fluids Mixing and propulsion Digestion Absorption Defecation
What are the muscles in the outer layers of the intestine?
circular muscle
longitudinal muscle
What does circular muscle fibres allow for and how?
the circular muscle fibres contract inwards
so that the lumen constricts
What does longitudinal muscle fibres allow for and how?
the fibres runn in a longitudinal direction
this allows for that peristaltic movement
How does the circular muscle fibres work in conjunction with the longitudinal muscle fibres?
circular - makes the lumen would get smaller
longitudinal - moves the ingested material along
allows the propulsion of the material through the alimentary tract
What types of mucosal tissues is there?
sub mucosa
muscularis mucosa
What are the three main layers of the alimentary tract going inwards?
serous
muscular
mucosal
What is the function of the serous membrane?
to reduce friction so that damage to the tissues and the muscular layers is minimised
How does the serous layer reduce friction?
it secretes a lubricating fluid
What are the two layers of the serous membrane?
outer epithelial layer (secretory) inner layer (connective tissue with vessels)
What is the function of the mucosal membrane?
lines internal organs / cavities exposed to external environment
secretes mucus
involved in absorption
What are the divisions of the GI tract?
Oral cavity Pharynx Oesophagus Stomach Small intestine caecum Large intestine (colon)
What are the three divisions of the pharynx?
nasopharynx
oropharynx
laryngopharynx
What are the three divisions of the SI?
duodenum
jejunum
ileum
What are the three divisions of the colon?
ascending
transverse
descending
What structures are in the oral cavity or pharynx that help with digestion?
Teeth
Palate
Tongue
Salivary glands
What are the functions of the tongue?
mixing
taste
swallowing
What are the functions of the pharynx?
directs food to oesophagus
blocks entry to trachea
What is the function of the soft palate?
it blocks nasal cavity during swallowing
How long is the oesophagus in cm?
25cm
At what intervetebral level is the oesophageal hiatus in the diaphragm?
around T10
Where is the stomach located?
between the oesophagus and the SI
lies under the diaphragm and under the heart
What is the shape / topography of the stomach?
J-shaped
What are the two openings of the stomach?
cardiac orifice
pyloric orifice
How does the stomach participate in digestion?
mechanical digestion - uses muscle
chemical digestion - uses gastric juices
Why does stomach rumbling occur?
the stomach muscles are contracting and trying to move around the contents but there aren’t any
What are the two types of omenta?
lesser
greater
What are the three layered muscles of the stomach?
longitudinal
oblique
circular
How long is the SI in length?
5 metres
Why is the SI so long?
to allow more time for the digestion and absorption
How long is the duodenum?
about 20-25 cm long
Is the duodenum retroperitoneal or intraperitoneal?
retroperitoneal - behind the peritoneum
What is the shape / topography of the duodenum?
C shaped
What are the four parts of the duodenum?
superior
descending
horizontal
ascending
Which ducts empty out into the duodenum?
pancreatic duct - pancreatic juices
gall bladder duct - bile
Where does the duodenum end?
the duodenal – jejunal flexure
Why do the jejunum and ileum get treated as one part?
bc it’s almost impossible to find the transition from one to the other
How long is the jejunum?
at least 3m long
Where is the jejunum measured from?
from the duodenal - jejunal flexure
to the ileocaecal junction
How do the projections on the jejunum help them with motility?
bc one attached and one free edges
bc they’re only attached at one end so they can move about so they don’t get damaged
From where does the LI span to?
end ileum to anus
How long is the LI?
1.5 m length; greater cross section compared to small
What are the four parts of the LI from RHS to LHS?
ascending
transverse
descending
sigmoid
Where are the ascending and descending parts of the LI located?
secondarily retroperitoneal - behind the peritoneum
What is the function fo the LI
absorption of water
forms faeces
expelling faceces
How did the ascending and descending parts of the LI become secondarily retroperitoneal?
they started off intraperitoneal
there were lots of the rotations and the movements in the gut
this causes them to posteriorly sit in the position that they will eventually exist in (on the flank of the body)
the rotations cause their peritoneum to obliterate when it comes into contact with the posterior wall
What is the role of sphincter muscles?
decide when substances should and shouldn’t exit through the digestive tract
What does the superior mesenteric artery supply?
the midgut
What are the branches of the superior mesenteric artery?
Jejunal arteries ileal branches arteries Middle colic arteries Right colic arteries Ileocaecal arteries
What does the Ileocaecal artery supply?
the ilium/caecum structure
What does the inferior mesenteric artery supply?
the distal third of the transverse colon
What are the three branches of the inferior mesenteric artery?
Left colic
Sigmoid
Superior rectal
Where are the superior and inferior mesenteric nodes located?
sup - towards the superior mesenteric artery branch
inf - towards the inferior mesenteric artery branch
What is the role of the mesenteric nodes?
drain the instestines of lymph
lymph travels through
lymph is constantly being checked for pathogens
Is somatic or autonomic innervation in charge of regulating the digestive tract?
somatic - don’t have conscious control over it
What is the effect of para and sympathetic activity on the rate of digestion?
para - increases rate; typically stimulates digestive activities (rest and digest)
sympa - decreases rate; inhibits GI secretion and motor activity, instead - GI sphincter and blood vessel contraction
Which nerves are responsible for the sympathetic autonomic innervation of the digestive tract?
prevertebral - splanchnic nerves
paravertebral - sympathetic trunk and ganglia
Which nerves are responsible for the parasympatic autonomic innervation of the digestive tract?
Vagus nerve (CN X) Pelvic splanchnic nerves (S2-4)
Which glands are associated with the gut?
Liver
Spleen
Gall bladder
Pancreas
What is the function of the liver?
processing ingested material
removing any toxins contained in processed material
Where is the spleen located?
on the left superior side of the stomach
Where is the gallbladder located?
under the liver
Where is the pancreas located?
posterior to the stomach
What are the teeth made up of?
four different types of tissue
What are the four different types of tissue that make up the teeth? (DECP)
dentin, enamel, cementum, pulp
What structures are contained in the pulp of the teeth?
connective tissue, nerves, and blood vessels
What is the hardest substance in the body?
enamel
