Aquaporins facilitate the transport of:
Ions
Glucose
Amino acids
Water
Related Questions
A researcher is studying facilitated diffusion of a novel solute 'X' across a cell membrane using an artificial lipid bilayer system. They observe that increasing the concentration of X on one side of the membrane increases the rate of transport, but only up to a certain point. Beyond this point, further increases in X concentration do not affect the transport rate. Which of the following BEST explains this observation?
The membrane has reached its maximum permeability for X.
The solute X is being actively transported at higher concentrations.
Saturation of the carrier proteins
The solute X is inhibiting its own transport through feedback regulation.
If two molecules A & B move in the same direction. This movement can be called
Antiport
Symport
Uniport
Guttation
Facilitated diffusion is different from simple diffusion because it:
Moves molecules against the concentration gradient
Uses carrier proteins
Requires ATP
Occurs only in plant cells
Facilitated diffusion
Needs a carrier protein
Is an active process
Occurs against the concentration gradient
Needs ATP
Active transport
    Releases energy
Requires energy
Produces ATP
Produces a toxic substance
What are the aquaporins in facilitated diffusion process?
    Membrane proteins
Carrier proteins
Channel proteins
Carrier lipids
If two molecules A & B move in the same direction. This movement can be called
Antiport
Symport
Uniport
Guttation
    Consider the following statements and choose the correct answer
I.    Carrier proteins are needed by both facilitated diffusion and active transport and are sensitive to inhibitors that react with protein side chain
II.    Different types of proteins present in the membrane plays a major role in both active as well as passive transport
III.    The carrier proteins needed by facilitated and active transport are specific
IV.    There is no need of energy to pump molecule against a concentration in active transport
V.    Transport rate reaches to saturation point, when all the active proteins are used
I, II, II, IV and V
I, II and III
V, IV and I
I, II, III and V
Which factor does NOT influence the rate of facilitated diffusion?
The concentration gradient of the transported substance
The number of carrier proteins in the membrane
The amount of ATP available
The temperature
In facilitated diffusion, saturation occurs when:
The concentration gradient disappears.
All carrier proteins are occupied by the transported substance.
The cell runs out of ATP.
The temperature decreases significantly.
