new Flashcards
lyonisation works how
inactivates one x chromosome copy(–> transcriptionally inactive) by wrapping it in heterochromatin
missense vs nonsense
both point mutations (substitution)
missense causes amino acid change
nonsense causes stop codon
how do nasal sinuses drain into nasal cavity
frontal= frontonasal duct
ethmoidal and maxillary = hiatus semilunaris
sphenoid= sphenoethmoidal recess
nasal sinuses innervated by
frontal =v1
ethmoidal=v2
maxillary =v2
sphenoid =v1
which nasal sinus infects most, and why
maxillary, drains from top
sensory innervation to
- nasopharynx
- oropharynx
- laryngopharynx
- larynx
cn v2
cn IX
cn X
cn X (internal branch of superior laryngeal= false vocal cords and above. recurrent laryngeal= true vocal cords and below)
muscular innervation to pharynx and larynx
pharynx
- all muscles = cn X
- except stilopharyngeus = cn IX
larynx = cnX
- all muscles = recurrent laryngeal
- except cricothyroid = superior laryngeal
chief cells secrete=
in stomach- pepsinogen and lipase
in parathyroid - PTH
saliva ph
7.2 ish
what increases and decreases hunger and where produced
ghrelin increases - stomach
leptin decreases - fat cells (in obesity however, increases hunger due to resistance)
where are vitamins absorbed
water soluble in jej
fat soluble in ileum
how is sodium, chlorine, water, potassium absorbed
cl- pumped in (bicarb out)
na+ actively in – water follows
k+ passively in
histology of oesophagus muscle
skeletal to smooth distally
swallowing stages and muscles
1 (vol). tongue, suprahyoid and buccinator (cheek) muscles push food up against roof–> oropharynx
- (invol) soft palate rises (tensor palatin and levator palatini) and this blocks nasopharynx.
hyoid bone goes up (mouth floor muscles), pharynx widens and shortens. epiglottis closes trachea - (invol) constrictor muscle contracts sequentially
pharynx and hyoid go down (infrahyoid), relax
upper oesophageal sphincter relaxes, peristalsis
bolus
chyme
whats swallowed
in tumtum
b12 route
binds with r protein in mouth. this protects it within the stomach. it seperates from r protein in duodenum due to protease(/hcl). absorbed in terminal ileum– intrinsic factor required.
endopeptidases vs exopeptidases
endopeptidases= split polypeptide in MIDdle,
(trypsin, elastase, chymotrypsin, pepsin)
exopeptidases= brush border, remove one amino acid from chain
hepatocytes derive from
endoderm
bile made from
cholesterol
liver vs skeletal glycogenolyis (x2)
liver- fasting
- direct to glucose (enzymes)
muscle- excercise
- indirect to glucose (no enzymes, via lactate)
good vs bad lipoproteins
good
- hdl.
- formed in liver
- removes excess cholesterol from tissues and blood (As bile)
bad
- ldl.
- formed in blood
- delivers cholesterol to tissues (membranes, steroid hormone production)
purine to
purine source
pyramidine to
uric acid
meat fish outmeal soft drinks (like phosphate)
cos2, h2o, urea
transamination
uses aminotrasnferase
Alanine aminotransferase removes amine from glutamate and adds it to pyruvate to form alanine and an alpha keto acid (used in Kreb cycle)
glutamate and pyruvate –> alanine and alpha ketoglutarate
oxidative deamintation
glutamate and water –> alpha ketoglutarate and ammonia