lecture 6 GI Flashcards
.5m^2 to 300m^2
after infoldings(fold of kerckring, villi, and microvilli)
exists in villi and microvilli transporters for absorbing enzymes to break down protein and carb 1 nd 2
1 and 2
tf cells in small intestine are most mature when at the crypts
F when at the microvilli
Label the channel and pump
channel on luminalside (requires Na to go downstream)
pump on basolateral
pump
gets Na secreted
doesnt require energy
gets Na absorbed
Na ends up in the lumen
gets Na absorbed
on interstitium and cap side
which of the following can pass paracellularly
ions
Water
Glucose
Nas
1 and 2
ions and water
1 and 2
TF tight junction are tight at proximal duodenum
F they are loosest at duodenum
Correct the statement
Tight Junction Form boundary between apical and basolateral domains of plasma membrane maintaining symmetrical distribution of membrane proteins
Tight Junction Form boundary between apical and basolateral domains of plasma membrane maintaining asymmetrical distribution of membrane proteins
what is absorbed after Na paracellularly?
Na H20 follow —-?
made of only alpha 1,4 glucose links?
amylose
cellulose
amylopectin
amylose
made of glucose beta 1,4 links
amylopectin
amylose
cellulose
sucrose
cellulose
tf cellulose cant be broken into single glucose mol.
T
made up of glucose alpha1,2 fructose bonds
sucrose
lactose
maltose
sucrose
made of glucose beta 1,4 galactose mol
sucrose
lactose
maltose
lactose
tf maltose makes up the least percentage of carbs and contains 2 glucose as it constituents
T
glu alpha 1,4 glu
where does alpha amylase cut?
internal glu alpha 1,4 glu
tf sucrase can break down maltase and maltriose
T
alpha dextrin is broken down into
glucose
galactose
fructose
Glucose
which of the following cant break down maltose and maltriose
lactase
sucrase
maltase
alpha dextrinase
lactase
digestion and absorption of monosach. happens
in the
1/3 of Si
2/3 of SI
3/3 of SI
1/3 of SI
SGLT1
na glucose/ galactose contrasport(only binds one)
na glucose/ galactose contrasport(only binds both)
na glucose/ fructose contrasport(only binds one)
na glucose/ fructose contrasport(binds both)
na glucose/ galactose contrasport(only binds one)
GLUT 5
transports Fructose into intestinal cell
transports fructose and glucose to blood
requires Na
is next to glut 2
transports Fructose into intestinal cell
Tf glut transport glucose, fructose, galactose into blood with Na
F
no Na
tf glut 5 is energized and carries fructose into the cell
f
its a facilitated carrier and does carry fructose into cell
tf
all proteins hve to be broken down into single aa to be transported
F
they can be di and tri peptides
tf peptidases are active in breaking down proteins(> 3 aa) to only single AA
F
it breaks down proteins(>3aa) to tri, di, single aa
1–>transfer di and tri peptide into cell. cytolosolic peptidase digest them to single aa once in cel
2single aa goes with Na into cell(using nrg of NA)
3 facilitated carrier of AA
TF on the Basolaateral membrane
the aa only gets to the cap side by facilitate transport
F
it can diffuse thru lipid bilayer
TF most water absorption comes from Smal intestine
T
which of the following does not absorb water by isoosmotic absorption
prox duodenum
jejunam
colon
ileum
prox duodenum
the proxima duodenum absorbs water thru
osmotic equilibration
tf absorption water is primary to absorption of solute
F it is secondary
tf most of the Na pumps are on the lateral side close to junction
T
Order it
then goes into interstitial space
Na goes downhill into cell.
pressure build up in interstitial space
attracts h20
and fluid travels to cap
Na goes downhill into cell.
and goes into interstitial space
attracts h20
pressure build up in interstitial space
and fluid travels to cap
tf the fluid absorbed in the small intestine cells
is isotonic to plasma
T
there isnt a huge requirement for increase in osmolarity for H20 to follor salt into interstitial space
TF small intestine proximal side has a large diff in voltage
f
small diff because leaky junctions and transfer of NA
tf during a meal CL is absorbed
F it is secreted
How does cholera affect Cl transport
camp is irreversibly act
Aden cyclase is irreversibly act
Dec Cl secreted
camp is irreversibly act
NT binds receptor and inc Camp thru aden cyclase. since it is irreversible it act a kinase to phos the CL channel. Cl leaves and Na and H20 subsequently follow. this happens in excess
Tf Ca is absorbed in the Small intestine
T
paracellular transport of ca in SI
is active
passive
happens at the duodenum
happens under low ca intake
passive
need adequate to high Ca intake and happens at ileum
Ca transport transceullulary
calbindin,channel, pump
pump channel, calbindin
channel , calbindin, pump
channel , calbindin, pump
tf the pump and calbindin are activated by vit d
in the transcellular transport of Ca
T
DMT1
proton dependent Fe import
Ferratin
stores Fe and is irreeversible
mobiferrin
form complex with fe
ferroportin
basolt. side
tf after Fe is transferred to blood it is transferred to transferrin(plasma protein)
t
Ferratin
inh by low body fe
when inh allows less absorbtion
inh by more body fe
when inh allows more absorption
more than 1 name which
1 and 4
hepcidin
degrades ferropotin and limits Fe absorption
which of the following doesnt supress hepcidin
anemia
hypoxia
erythropoeises
iron loading
iron loading increase hepicidin
hypoxia
increases hepcidin
increases HIF and transporters
decreases HIF and transporters
increases HIF and transporters
low iron levels
inc hif and transporters
high O2 and Fe cell levels
dec. HIF and transporters
hereditary chromatosis
deficiency in hepcidin
