:P Flashcards
the muscles in the pharynx are innervated by which nerve, except for the stylopharnygeal muscle - which is innervated by which nerve?
- all pharynx muscles innervated by: vagus nerve
EXCEPT:
- stylopharyngeus muscles which is innervated by the glossopharyngeal nerve (CNIX).
what is the migrating motor complex?
where can it originate?
what is its functions? (2)
migrating motor complex: propagating contractions every 90-120 mins. 3 phases
- *originates**:
a) stomach - vagus dependent
b) small intestine - vagus independent
functions:
a) clear undigested material
b) prevents bacteria overgrowth
what anatomical features of the colon ensure that peristalsis is modified? [2]
how does bolus move along colon? (2)
what anatomical features of the colon ensure that peristalsis is modified?
- get bulges of outer circular muscle (haustra), which are held together by three bands of circular muscle: taenia
- taenia can contract in either direction
how does bolus move along colon? (2)
- constrictive ring occurs (giant migrating concentration) and haustra disappear (!) from a portion of the ascending colon
~20cm of the colon distal to the constrictive ring lose their haustrations and contract as a unit, propelling faecal material into the transverse colon
cardia and pyloric mucosa:
- where find?
- cell types?
- function?
- what are nuclei like?
cardia and pyloric mucosa:
- *- location**
i) cardia: start / oesph -> stomach
ii) pyloric: end / stomach -> duo
- cell types: columnar epithelium - mucous secreting cells
- function: protec the oesphageal epithelium and pyloric mucosa against gastric juices
- nuceli: small & close to basal domain
Q
sensory innervation of the pharynx is from which nerve?
what are the constrictor muscles called in pharynx? - innervated by?
sensory innervation of the pharynx is from glossopharnygeal nerve
constrictor muscles: superior, middle and inferior constrictors. **vagus nerve innervation
_baso:
- sensory innervation = CNIX
- motor inneration = CNX_**
- which nerve plexuses do u find in the oesphagus? (2) and where do find them?
- *- meissner plexus:** submucosal tissue
- *- auerbach’s plexus:** myenteric - betweeen circ and long. muscle layer
(in the whole body): rank antibodies in their order
IgG most common 75% of Ig are IgG
IgM 3rd most common but 1st to be made
IgA 2nd most common
IgD very low
IgE least common in serum as binds tightly to basophils and mast cells even before interacting with antigen
name of the sphincter muscle which encircles the mouth:?
name of the sphincter muscle which encircles the mouth: orbicularis oris
in the anal and rectal area what are the different cell types in:
colorectal zone?
anal transitional zone?
squamous zone?
in the anal and rectal area what are the different cell types in:
colorectal zone: simple columnar epi
anal transitional zone: transition betwen simple columnar and and stratified squamous epi
squamous zone: stratified squamous
which part of muscaluris muscosa
- becomes internal anal sphincter?
2 extends over sphincter & attaches to CT? - becomes external anal sphincter?
which part of muscaluris muscosa:
circ muscle: becomes internal anal sphincter
long muscle: extends over sphincter & attaches to CT
skeletal muscle: external anal sphincter
which hormone is released when have hypocalcemia?
what is it effects? (3)
what is 1. inhibited by?
fall in calcium: PTH (parathryoid hormone) rises - restores calcium back to normal by:
- Increased renal Ca++ reabsorption.
- Increased bone Ca++ release.
- Increased gut absorption via release of vitamin D (1,25vitD).
The release if PTH is inhibited by raised Ca++ levels.
what is the differnece in the role of the intrisic and extrinsic muscles of mouth?
intrinsic muscle: change shape
extrinsic muscle: change position
orbicularis oris and buccinator are both innnervated by which nerve? [1]
orbicularis oris and buccinator are both innnervated by facial nerve [1]
Q
which antibody is commonly (1/200) deficient?
why is this very often not recognised?
A
IgA deficiency is quite common, yet no one knows they have it.
This is because IgM has a J chain so IgM undergoes a compensatory response and does the same job IgA would
what are two seperate roles of aldosterone? [2]
- restores BP, reabsorbed salt & water lvls (not excrete as much)
- restores K loss !
(two totally differnet systems! )
which muscles of mastiication are involved in:
a) elevation and retraction?
b) elevation and protrusion?
c) depression and protrusion?
d) elevation and protrusion?
a) elevation and retraction: temporalis
b) elevation and protrusion: masseter
c) depression & protrusion: lateral pterygoid
d) elevation and protrusion: medial pterygoid
Q
what is the special and general sensory innervation for the a) anterior 2/3 tongue? b) posterior 1/3 tongue
- *a) anterior 2/3 tongue**
- special: facial -> chorda tympani
- general: lingual nerve (V3)
- *b) posterior 1/3 tongue**
- special: glossopharyngeal
- general: glossopharyngeal
what are the two groups of muscles in the tongue?
how do they move the tongue?
innervated by?
- two groups: intrinsic (superficial) & extrinsic (deep)
- *- intrinsic** changes shape
- extrinsic changes position
- both innervated by hypoglossal nerve (CN XII)
IgD
- role?
- shape??
- how common?
- contains?
IgD
- role: antigen receptor on B cells that have not been exposed to antigens.
- activates basophils and mast cells = make antimicrobrial factors
- *- activates B cells**
- how common: very low levels
describe the structure of IgA and IgM - how many binding sites do they have?
what do they both contain?
IgA: dimer !! (know this) - can form 4 binding sites
IgM: pentamer - can form 10 bindings sites
= form multimers
- both have J chain: (The joining (J) chain is a small polypeptide, expressed by mucosal and glandular plasma cells)
submanidublar gland recieves parasympathetic innervation from which nerve?
- submanidublar gland recieves parasympathetic innervation from facial nerve (CN VII) nerve
how does pit. gland control FSH & LH hormone release?
why is it more complex in women then men?
hypothalamic hormones: GnRH + kisspeptin
regulate release of: FSH and LH from pituitary.
FSH & LH cause sex steroid release (testosterone / oestrogen) , ovulation, spermatogenesis.
in women: estradiol +ve and -ve feedback depends on stage of menstruation
name for the muscle that causes upper oesphapgeal sphincter? [1]
- is produced by which skeletal muscle: cricopharyngeus muscle
- in the small intestine, enzymes are secreted by small intestinal cells called?
- what are the folds called in the small intestine?
- what are the main histological feature of small intestine? (2)
- what are the lieberkuhns crpyts?
- in the small intestine, enzymes are secreted by small intestinal cells called enterocytes
- what are the folds called in the small intestine: plicae circularis
- what are the main histological feature of small intestine: villi (projections of the mucosa) & microvilli
4. lieberkuhns crpyts: gland found in between villi
which nerve provides sensory innervation for the entire face?
- how is it split up? (3)
- which of ^ supply superior teeth?
- which of ^ supply inferior teeth?
- *trigeminal nerve (CN V):**
- ophthalamic (V1)
- maxillary (V2)
- mandibular (V3)
- maxillary V2 —> superior alveolar nerve: supplies superior teeth
- mandible V3 —> inferior alveolar nerve ( –> mental nerve) supplies inferior teeth
how do u tell the difference between paneth and endocrine cells?
Paneth granules are above nucleus (supranuclear) & appear pink = P4P
endocrine granules are beneath the nucleus (subnuclear)
what type of hormones are thyroid hormones?
produced from what?
what is active / inactive names?
how does it circulate around body?
biological amines - produced from tyrosine
T4 (inactive) is produced by thyroid gland -> converted to T3 to be active (via deiodinise enzyme)
circulates as T3, but attached to thryoid binding globulin
Q
how does peristalsis occur in oesophagius ? (primary / secondary waves?)
peristalsis:
- bolus enters striated muscle, initiates primary peristaltic wave. pressures changes / waves of contraction push bolus down.
- this stimulates stretch receptors = secondary peristaltic wave of smooth muscle (back up secondary wave) pushes the bolus into the stomach
what is the ileal brake caused by? [1]
what does cause secretion of ? [2]
- fats reach the ileum (even tho theyre meant to have been absorbed in duodenum)
- causes release of peptide YY & glucagon-like peptide-1 (GLP-1) by enteroendocrine cells
= slows gastric emptying
parotid gland recieves parasympathetic innervation from which nerve?
parotid gland recieves parasympathetic innervation from glossopharyngeal nerve
Q
how do u tell histoligcally if you have significant oesophagitis? (2)
how do u tell histoligcally if you have barret oesph? (1)
how do u tell histoligcally if you have CD? (3)
significant oesophagitis: eosinophils in squamous mucosa & neutrophils
barret oesophagus: complication of chronic gastro reflux disease (GERD). characterised by change of squamous mucosa in oesph to simple columnar epithelim
CD: atrophy of villi (1), hyperplasia of intestinal crypts, more lymphocytes
whats the role of the soft palate?
soft palate: elevates during swallowing to prevent food moving into nasal cavity
muscles of mastication are supplied by which nerve?
manidublar nerve V3
for anterior 2/3 tongue:
which nerve supplies the
a) special sensory (taste)
b) general sensory (pressure etc)
c) motor sensory?
anterior 2/3 tongue:
nerve supplies the
a) special sensory (taste): CN VII - facial nerve - chorda tympani
b) general sensory (pressure etc): CN V - trigeminal nerve (V3, mandibular nerve)
c) motor sensory: hypoglossal nerve - CN XII
for posterior 1/3 tongue:
nerve supplies the
a) special sensory (taste): glossopharnyngeal nerve (CN IX)
b) general sensory (pressure etc): glossopharnyngeal nerve (CN IX)
c) motor sensory: hypoglossal nerve - CN XII
describe how movement of stomach smooth muscle is initated? at which cells?
human stomach movement:
- random depolarisation of interstitial cells of cajal is communicated to smooth muscle cells, via gap junctions
- slow waves of electrical activity propagte from dominant pacemake in corpus (see photo)
eustachian tube is made from what?
fibrocartliage !
name the three papillae in the tongue
which have taste buds (2)
- fungiform papillae: located anteriorly
- filiform papillae: loacted centrally
- circumvallate papillae: located posteriorly
fungiform and circumvallate = taste buds
what are the main histological differences between the duodenum, jejunum and ileum?
duodenum:
- have brunner’s glands in submucosa: produce secretion that neutralises acidic chyme from stomach
- villi are shorter
jejunum:
- no brunners glands
- long, finger like villi with well developed lacteal (lympathic vessel) in the core
ileum:
- *- peyers patches** (lymphoid aggregations / nodules in the mucosa. form part of GALT
- shorter villi
- most goblet cells
- prominant fat in submucosa
where is endocrine fucntion of pancreas located?
islets of langerhans
what normally prevents defecation? (2)
- *defecation prevented by:**
- Tone of internal anal sphincter & puborectalis
- Mechanical effects of acute anorectal angle. The pubic symphysis and angle act as a mechanical obstruction to defecate moving to the anus.
why is the gut vulnerable to infections? (2)
- has only a single layer of epithelium (not much of distance between BV and lumen: blood in stools) [1]
- *- lumen = essentially outside the tissues** [1]
what are the 3 paired salivary glands?
what are they innervated by?
where do each of them drain into?
- *- parotid glands** = glossspharyngeal nerve = drain into upper 2nd molar
- *- sublingual glands =** facial nerve = drain into either side of frenulum of the tongue
- *- submandibular gland**s = facial nerve = drain into either side of frenulum of the tongue
which Ig is the only antibody capable of crossing the placenta to give passive immunity to the fetus?
a) IgG
b) IgM
c) IgA
d) IgE
e) IgD
which Ig is the only antibody capable of crossing the placenta to give passive immunity to the fetus?
- *a) IgG**
b) IgM
c) IgA
d) IgE
e) IgD
what are the dudenal and jejunal brakes?
dudenal and jejunal brakes:
- food goes into the duodenum, might be too big - like long chain fatty acids / amino acids. causes the release of CCK
- release of CCK activates vagal efferents
- as a result of vagal efferents:
* *- reduces opening of pyloric sphincter
- reductions contractions in corpus
- enhances relaxation of fundus**
within the GI:
where are the CD4 T cells usually found?
where are the CD8 T cells usually found?
what do each do there?
CD4 T cells usually found: cells sit in the lamina propria to produce lots of cytokines (primarily Th1 cells)
CD8 T cells usually found: epithelium, kill virally infected cells
out of submanidublar and sublingual duct orifaces - which is more medial to the frenelum?
submandibular
the hard palatine is composed of which bones (2)
where is the soft palate in relation to the hard palate?
what does soft palate do when eating?
soft palate is innervated by?
hard palate: maxilla & palatine
soft palate: composed of muscles posterior to the hard palate - elevates during swallowing to prevent food entering nasal cavity
soft palate is innervated by vagus nerve
main role of thryoid hormones? (1)
how controlled?
- negative feedback - how? (1)
- how else (4)
- increases metabolic rate
- negative feedback control: T3 inhibits pituitary release of TSH
- local control mechanism:
i) deiodinase expression
ii) thyroid hormone uptake transporter expression
iii) thyroid hormone receptor expression
iv) release from thyroid binding globulin
what is the correct label for this strucutre?
a) rotundudm foramen
b) manibular foramen
c) mental foramen
d) ovale foramen
e) hypoglossal foramen
what is the correct label for this strucutre?
a) rotundudm foramen
b) manibular foramen
* *c) mental foramen**
d) ovale foramen
e) hypoglossal foramen
how does hypothalamus communicate with the anterior pit. gland? and posterior pit gland?
- hypothalamic hormone binds to anterior pituitary cell target (all are stimulatory except Dopamine which is inhibitory) via portal system
- causes release of anterior pituitary hormone - releaed into blood
- hypothalamus have long axons that cause release of posterior pituitary hormones (ADH and oxytocin)
Adrenal gland has different cells: ZG, ZF and ZR that all secrete different hormones
how do u produce many different hormones from same organ?
- different enzymes expressed in the different zones (e.g. ZG/ ZF/ ZR will express different horomones) - causes cholerestrol to be turned into different things
what is the squamocolumnar junction?
squamocolumnar junction: abrupt change in the mucosa from stratified squamous (oesphagus) to columnar cells (stomach) (and glands)
Q
what two things specifically make u hungry?
- release of hormone ghrelin
- *- phase three of migrating motor complex**
draw basic structure of IgA, IgM, IgG, IgD, IgE
IgA = dimer ! = 4 binding sites
IgM = pentamer = 10 binding sites
IgG, IgD, IgE = monomers = 2 binding sites
