• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

Card Range To Study

through

image

Play button

image

Play button

image

Progress

1/24

Click to flip

Use LEFT and RIGHT arrow keys to navigate between flashcards;

Use UP and DOWN arrow keys to flip the card;

H to show hint;

A reads text to speech;

24 Cards in this Set

  • Front
  • Back
permeability depends on?
size and solubility
which molecules are easier to diffuse?
small hydrophobic
protein-aided transport
transport depends on electrochemical gradient
permeability depends on?
size and solubility
2 types of transport
passive & active
which molecules are easier to diffuse?
small hydrophobic
passive transport
involves carrier protein carries high conc. to low
protein-aided transport
transport depends on electrochemical gradient
his180
narrows diameter of channel
arg195
repels cations like h30+
arrangement of dipoles in aquaporins
2 short helices with positively charged oriented
to the pore which prevents hydrogen bonding between adjacent water
molecule
glucose transporter
(structure, etc.)
12 transmembrane helices, contain hydrophobic and hydrophilic residues, pose is hydrophilic and h-bonds to glucose
diabetes insipidus
lack of ADH receptors, collecting duct aquaporins are messed up
primary active transport
energy released by atp hydrolysis drives solute movement against electrochemical gradient
secondary active transport
energy released during movement of a solute down its gradient is used as driving force to pump other solutes against
p-type ATPase:
reversibly phosphorylated by ATP as part of transport cycle
SERCA(what it does, structure, where to find?)
transports calcium, 10 transmembrane helices and 3 globular domains:nucleotide binding, actuator, phosphorylation
found in sarcoplasmic reticulum
What does Ca release do?
binds to troponin, causes tropomysin to move, exposes myosin binding site on actin
what causes cystic fibrosis?
loss of function of cl- transporter (which is abc) btw
ABC transporter (structure, etc.)
2 transmembrane, 2 nucleotide binding domains
ex. MDR, CFTR
ion channels
have hydrophilic pores that have high selectivity and transport efficiency;
transport of ions occur passivel
K+ channel (structure, etc.)
4 identical transmembrane subunits, have inner, outer, and pore helix, (pore has selectivity loop w/ carbonyl backbone)
voltage gated sodium channel
i. Structure: single, large polypeptide organized into 4 domains clustered around a
central channel
ii. Features:
1. Voltage sensor: helix 4 with a high density of Arg residues; moves into
membrane in response depolarization, which triggers opening of
activation gate of the channel
2. Inactivation gate: a ball-like protein domain on the cytoplasmic surface of
the sodium channel that blocks the channel; ensures the action potential
propagates in one direction
acetylcholine receptors
a. Structure: 5 subunits, each having 4 transmembrane helical segments (M1–M4)
i. Where does acetylcholine bind? On the two alpha subunits, so two Ach are
required to open the channel
ii. Explain how binding of Ach opens the channel.
Ach binding causes twisting of M2 amphipathic helices, so that smaller, polar
residues line the channe