cell bio ch. 8
___-Type ATPases are ATP-Binding Cassette, they compromise a large superfamily of transport proteins that are related to each other in amino acid sequence and molecular mechanism
ABC
___-Type ATPases transport ions, sugars, amino acids, peptides, and polysaccharides
ABC
____-Type ATPases transport a variety of solutes, but the solute transported is specific to the particular ABC transporter of the superfamily
ABC
F-Type ATPases function to use either the energy from sugar oxidation (respiration) or the energy or solar radiation (phosphorylation) to produce a transmembrane proton gradient that drives ____ ____
ATP synthesis
_-Type ATPases are factor type, are found in bacteria, mitochondria, and chloroplasts, they have 2 components (integral membrane and peripheral membrane ATPase)
F
_-Type ATPases, are phosphorylation types, reversibly phosphorylated by ATP as part of the transport mechanism, with an aspartic acid residue phosphorylated, located on the plasma membrane, pumps protons and cations
P
there are 4 types of transport ATPases 1. 2. 3. 4.
P-Type, V-Type, F-Type, ABC-Type
Indirect/secondary active transport is a ___/___ symporter
Sodium/Glucose
_ - Type ATPases are vacuole type and pump protons into such organelles as vacuoles, vesicles, lysosomes, endosomes, and golgi complexes. integral membrane protein and a peripheral ATPase
V
____ transport occurs when a substance needs to be transported against a gradient, and goes from an area of low concentration to an area of high concentration
active
a carrier protein is an ____ protein that alternates between two conformational states, such that the solute binding site of the protein is open or accessible first to one side of the membrane and then the other
allosteric
carrier proteins are _____ to their enzymes in their specificity and kinetics
analogous
indirect active transport is a ____ of calcium and potassium ions
antiport
transmembrane channels that allow the rapid passage of water
aquaporins
active transport always moves solutes ___ from thermodynamic equilibrium, ____ the concentration gradient or ______ the electrochemical potential, and always ____ the input of energy
away, up, against, requires
___ _____ bind one or more solute molecules on one side of the membrane and then undergo a conformational change that transfers the solute to the other side of the membrane
carrier proteins
_____ can either be uniporters, symporters, or antiporters
carriers
transporters are subject to _____ _____
competitive inhibition
the rate of simple diffusion is directly proportional to the ______ ______
concentration gradient
active transports enables the cell to maintain ____, _______ intracellular concentrations of specific inorganic ions
constant, non-equilibrium
____ always moves solutes toward equilibrium
diffusion
depending on the energy source, active transport is regarded as being either ____ or ____
direct, indirect
distinction between active transport and simple or facilitated diffusion concerns _____ __ ______
direction of transports
active transport has ____, it transports a solute across a membrane in one direction and will not transport that solute actively in other direction
directionality
active transport mechanisms can be divided into categories depending on the 1. source of ______ 2. whether or not two solutes are transported _______
energy, concomitantly
simple diffusion is always an ____ process requiring no input of metabolic energy
exergonic
direct or primary active transport is the accumulation of solute molecules/ions on one side of the membrane and is couple directly to an ______ chemical reaction, most commonly the ______ of ATP
exergonic, hydrolysis
if no input of energy is required it is called _____ _____ because the solute still diffuses down the concentration gradient
facilitated diffusion
P Type ATPases pump protons and cations are some are ____
flippases
most ion channels are ___, meaning that they open and close in response to some stimulus
gated
example of facilitated diffusion
glucose transport
transporters or permeases are carrier proteins and they have a ___ degree of specificity for the solutes
high
ion channels are ____ selective, allowing the transport of a ____ type of ion
highly, single
channel proteins facilitate diffusion by forming _____ transmembrane channels
hydrophilic
ABC-Type ATPases are either ____ or ____ of molecules
importers, exporters,
transport proteins involved in facilitated diffusion of small molecules are ____ _____ proteins that contain several _______ segments
integral membrane, transmembrane
V type ATPases contain an ____ membrane protein and a ____ ATPase
integral, peripheral
in most cells osmosis makes water move _____ because the concentration of solutes is almost always higher inside a cell than outside
inward
transmembrane proteins that allow rapid passage of specific ions in the direction of the electro-chemical gradient
ion channels
three kinds of transmembrane protein channels
ion channels, porins, aquaporins
Indirect active transport is driven by ___ _____
ion gradients
lipid bilayers are relatively impermeable to ____
ions
porins are larger and ___ specific
less
____ gated channels are triggered by binding specific substrate to channel
ligand
_________ channels respond to mechanical forces that act on the membrane and are triggered by pressure
mechanosensitive
individual molecules are free to diffuse in both directions, but the ____ ____ will always be in the direction of the minimum free energy
net flux
simple and facilitated diffusion are both _____ with respect to the membrane; solute can move either in or out, depending on the concentration gradient
nondirectional
lipid bilayers are permeable to _____ molecules
nonpolar
membranes have a hydrophobic interior, so simple diffusion is good for small, relatively _____ molecules, such as carbon dioxide, oxygen, ethanol, water
nonpolar
_____ is the diffusion of water across a selectively permeable membrane in response to differences in solute concentrations
osmosis
P Type ATPases are located on the ____ membrane
plasma
transmembrane proteins that allow rapid passage of various solutes, are found in the outer membrane of the mitochondria, chloroplast, and many bacteria.
porins
there are two types of channel proteins 1. 2.
porins, ion channels
F-Type ATPases are involved in _____ transport
proton
V type ATPases ____ protons into organelles
pump
active transport allows various substances to be ____ from the cell or organelle
removed
F-Type ATPases also facilitate ____ process to synthesize ATP
reverse
carrier proteins show ____ kinetics, and the Vmax and Km for a transporter can be determined
saturation
ions associate with water to form a ____ __ _______
shell of hydration
unassisted net movement of a solute from a region of high concentration to a low concentration region
simple diffusion
three different mechanisms involved in the movement of solutes across membranes
simple diffusion, facilitated diffusion, active transport
3 main factors that affect the diffusion of solutes
size, polarity, and charge
generally lipid bilayers are more permeable to ____ molecules than larger molecules
smaller
indirect active transport uses ____ ion if an animal or ____ gradients if a plant/bacteria/fungi for transport
sodium, proton
direct/primary active transport is a ___/___ pump that is a P-Type ATPases
sodium/potassium
some transporters are also _____
stereospecific
Indirect active transport is a ____ of sugars and amino acids
symport
indirect or secondary active transport can be ____ or _____
symport, antiport
active transport provides ___ major functions in cells and organelles
three
molecules that are too large or too polar to cross the membrane can move in and out of cells with the help of ___ ___
transport proteins
active transport is a _____ or _____ process
unidirectional, vectorial
indirect or secondary active transport depends on the co-transport of two solutes with the movement of one solute ____ the concentration gradient driving the movement of the other solute ___ its gradient.
up, down
active transport makes the ____ ____ _____ _____ from the environment possible
uptake of essential nutrients
____ gated channels respond to changes in membrane potential
voltage