Transporters Quiz Chapter 12

for glucose transporters, are they active or passive

passive (facilitated diffusion)

for glucose transporters, how many conformations are there, what other important factors are there

3 conformations

randomly occuring

reversible

what stimulates glucose uptake

insulin

what happens to glucose when uptaken in liver

glucose is phosphorylated and maintains gradient

what is the stored version of glucose

glycogen

what happens when you are hungry

glucagon stimulates glycogen breakdown, increased sugar level, glucose binds to internally displayed sites, release of glucose from liver

what is important about Na and Glucose symport

they must bind together

entry is favored over leaving the cell

what is the process of glucose and Na being taken up in gut

Na and glucose take up in symport

Na leaves basally through na K pump

glucose leaves through glucose passivetransporter

What is important about calcium pumps

it has 4 domains

releases 2 calcium ions

ATP binds, releasing phosphorus which brings domains together

What are the 4 domains

Activator

Cabinding

ATP binding

Phosphorylation domain

where is the concentration of H+ mainly located in plants and animals

Vacuole and lysosome

what is different between plant and animal H pumps

plants do not have Na-K symports

H+ symport and H+ ATPase drive movement of H+ ions

is the H+ leaving the bacteriorhodopsin the same as the one that enters

NO

What is important about the NA-K pump

moves both against graident

ATP hydrolysis is energy source

Plant glycoside Oubain halts production

1/3 of all energy consumption

what type of protein is a Na/K pump

tetramer

2 alpha- transport

2 beta- assembly

how does the Na/K pump function

Na enters pump, is ejected after phosphorylation, and causes conformational change

when K binds, phosphate removes, allowing entry of K

what way does calcium normally move

into the cell

where does sodium normally move

inside the cell

where does potassium normally move

outside the cell

where does hydrogen normally move

inside the cell to the lysosome or the vacuole

where does glucose normally move

inside the cell

where does Na and glucose normally move

inside the cell