Summary Alimentary Flashcards
what compromises the pharyngeal plexus and what type of fibres are present in it?
Vegus nerve fibres
glossopharyngeal fibres
motor/sensory nerve fibres
what vessels are closely related to the pharyngeal plexus?
internal and external corroted artery
name the pharyngeal constrictors.
superior, middle, inferior
how to the pharyngeal constrictors differ in arrangement compared to the rest of the GIT?
they have inner longitudinal and outer circular arrangements of muscle
what role do pharyngeal constrictors perform?
what happens if the nerve supply to this became damaged?
how would you test for this?
constriction of pharynx
food can’t pass down sufficiently
ask patient to say ‘ahhh’ if uvula goes to 1 side the nerve supply is damaged
describe the muscle layers in the muscular externa as you move from superior to inferior?
muscle is strained in the upper third sad transitions to smooth muscle in its lower third.
what are the anatomical regions of the stomach?
cardia, funds, pylorus, body (antrum)
what attaches to the greater curvature of the stomach?
greater omentum (yellow fatty tissue)
what is contained within the greater omentum?
adipose tissue
lymphatics
blood vessels
nerves
what is the role of the greater omentum?
encases infection
what structures are closely related to the oesophagus?
- lines in neck thorax and abdomen
- posterior to trachea and heart
- pierces diaphragm
how do muscle types vary throughout the length of the oesophagus?
upper - skeletal
middle - mixed
lower - smooth
what form the lower oesphageal spincter?
diaphragm
what is the function of the temporalis?
elevation and retraction of mandible
what is the nerve supply of the temporalis?
trigeminal nerve (mandibular division)
what is the function and nerve supply of the buccinator?
maintains food in middle of oral cavity
- facial nerve (buccal branch)
what common pathology mat result in the buccinator not functioning and what are the functional consequences for patient?
stroke
- which leads to drooling
= can’t maintain food in the middle of the oral cavity
what are the origins and intersections of the masster muscle?
originates from zygotic arch (maxillary process of zygomatic bone).
inserts onto angle and lateral surfaces of the ramus of the mandible.
what is the function of the masster?
elevation and protrusion of the mandible
what is the nerve supply to the masster?
mandibular division of the trigeminal nerve
how would you clinically test the integrity of the masster muscle?
get patient to clench teeth
- feel the bulk and power of the muscle
how do the secretions produced by the parotid gland enter the oral cavity?
pass through buccinator to open opposite the 2nd upper molar tooth
what nerve passes through the buccinator muscle?
facial nerve
what type of secretions do the paranoid glands produce?
serous
(watery)
what are the 3 major salivary glands and what secretions do they produce?
parotid gland = serous
submandibular = mixed seromucinous
sublingual = mucous
what are the components of the pharynx?
nasopharynx
oropharynx
laryngopharynx
what are the anatomical boundaries of the nasopharynx?
base of skull and soft palate
what types of lymphoid tissue are closely related to the opening of the auditory tube?
pharyngeal and tubal tonsils
what does the auditory tube communicate with and why is this such a problematic site in children?
middle ear
its short and straight in children so allows easier access for infection
what are the folds called on the inner lining of the stomach?
rugae
what are the different cell types in cardia, body and pylorus of stomach?
c - mucous
b -parietal cells
p -mucous
what is the material called that is churned in the stomach?
chyme
what helps with the churning of chyme in the stomach?
muscularis propria and externa
what are the divisions of the gut and which one does the stomach come under?
foregut = stomach
midgut
hindgut
what type of cells exist in the gastric lining?
what are they produce?
parietal cells = produce hydrochloric acid
chief cells = found in lower regions and produce pepsin
mucous/surface mucous cells = produce mucosa
what rule can be applied (site, incidence, size, %) for population affected with meckel’s diverticulum?
RULE OF 2
- within 2 feet from ileocaecal valve
- it affects 2% of population
- if symptomatic it presents before the age of 2
- approximately 2 inches long.
what cell types are present in meckel’s diverticulum?
gastric, pancreatic or colonic mucosa
- mixture of these
what is periodontitis?
ill mucosa is eroded which leads to inflammation of peritoneum
- ruptures gastric tissue
what is the function of the gallbladder?
concentrate and store bile.
what is the duct called that comes from he gallbladder?
cystic duct
what is bile?
Contains water, cholesterol, bile pigments, phospholipids and bicarbonate
responsible for fat digestion
what is gallstones?
crystalline bodies made of cholesterol or bilirubin and calcium salts
what are they 2 main functional regions of the pancreas gland?
exocrine (hormonal)
endocrine (digestive)
what functional group forms the bulk of the pancreas?
exocrine (99%)
what is the most common pathology to affect the pancreas?
diabetes millitus
what is the blood supply for the pancreas?
where do these vessels arise from?
superior and inferior pancreaticoduodenal arteries
- from gastroduodenal and superior mesenteric arteries respectively
where does the blood in the hepatic portal vein arise from?
GI organs, non-paired abdominal organs ie. small and large intestine
what vessels unite to prom the hepatic portal vein?
superior mesenteric vein
splenic vein
where do anastomoses (joining vessels) occur?
oesophagus & stomach
- can become enlarged in portal hypertension
what is portal hypertension?
why is it so dangerous?
increase in pressure in the liver
- results in raised pressure in oesophageal and gastric vessels
- may rupture resulting in haematemesis
what division of the gut does the coeliac trunk supply?
foregut
what division of the gut does the superior mesenteric artery supply?
midgut
where do the coeliac trunk and the superior mesenteric artery originate from?
abdominal aorta
what are the 4 lobes of the liver called?
left
right
caudate
quadrate
what is the function of the liver?
produce bile
synthesise proteins
inactivate hormones and drugs
coagulation
where does bile produced in the liver open into in the intestinal tract?
via the major duodenal papilla
through the sphincter of oddi
into the 2nd part of duodenum
what is the arterial supply of the liver?
hepatic artery
where does the arterial supply of the liver (hepatic artery) arise from?
coeliac trunk
what other structures are closely related to the coeliac trunk?
hepatic portal vein
bile duct
what is the region called where all structures enter the liver?
porta hepatitis
what is the round ligament of the liver?
remnants of the umbilical vein which lies in the free edge of the falciform ligament
what is the purpose of the umbilical vein in foetal life?
bypasses the liver to allow nutrients to reach foetus directly rather than being processed in the liver
name some other anatomical structures closely related to the liver?
Diaphragm, stomach, gallbladder, large intestine (transverse colon/hepatic flexure), right kidney, right and left costal margins, inferior vena cava, duodenum, oesophagus
what cell types are present in the Islets of Langerhan’s?
alpha beta and delta cells
what do alpha, beta and delta cells secrete in the Islets of Langerhan’s?
a - glucagon
b - insulin
d - somatostatin
what pathology can be associated with defects of the beta cells in the pancreas?
diabetes melitus
