U2T7 – Transport Across Membranes

Other than glucose, which substance can be absorbed from the ileum via co-transport?

During co-transport of glucose in the ileum, active transport is needed to establish a concentration gradient of which substance?

Which protein needs to be used first in the co-transport of glucose across a membrane. For example in the ileum.

In the above diagram, there are three membrane proteins: A, B and C. Which represents where facilitated diffusion occurs?

In the above diagram, there are three membrane proteins: A, B and C. Which represents where co-transport occurs?

Would the number of carrier proteins present affect the rate of active transport across a membrane?

True or False: Facilitated diffusion can use ATP

True or false : Active transport can go down a concentration gradient, or up a concentration gradient.

True or false : Facilitated diffusion can use channel proteins or transport proteins, but active transport only uses transport proteins.

In the above experiment, two flasks contained identical masses of animal tissue, identical volume of a solution containing sodium ions, but an inhibitor of ATP production in flask F. Why did flask F plateau?

In the above experiment, two flasks contained identical masses of animal tissue, identical volume of a solution containing sodium ions, but an inhibitor of ATP production in flask F. Scientists concluded that flask G took up sodium ions by active transport. What is the evidence of this?

a) Uptake in flask G much greater than in flask F , showing use of ATP in flask G

b) Sodium ion concentration in flask G falls to zero, showing uptake against a concentration gradient

In the above experiment, two flasks contained identical masses of animal tissue, identical volume of a solution containing sodium ions, but an inhibitor of ATP production in flask F. Calculate the rate of the uptake of sodium ions in flask G, in the first 20 minutes.

True or False: In order to function, carrier proteins have to change shape.

Which type of membrane protein is not involved in facilitated diffusion?

Does a concentration gradient need to be established before facilitated diffusion can take place?

Which of the following factors when increased, will decrease the rate of diffusion?

a) The Concentration Gradient

b) The Surface Area

c) The Diffusion Pathway

Which of the following factors when increased, will increase the rate of diffusion?

a) The Concentration Gradient

b) The Surface Area

c) The Diffusion Pathway

Which part of the phospholipid bilayer prevents sodium ions leaving via simple diffusion?

Why can't glucose diffuse directly through the phospholipids?

Which of the following molecules can diffuse directly through the phospholipid bilayer?

a) Oxygen
b) Carbon Dioxide
c) Lipids