Module 3/ Transport proteins

Question 1

Transport proteins

Answer 1

Transport proteins are membrane proteins that can modify the permeability of the membrane by allowing only specific molecules to cross.

Question 2

Passive transport

Answer 2

Passive transport does not require energy

Question 3

Facilitate diffusion

Answer 3

Membrane protein can facilitate diffusion following the concentration gradient.

Question 4

Uniporter

Answer 4

Transports a single molecules. Activated by ligand, physical deformation, change membrane potential or always “ON”.

Question 5

Ion channel

Answer 5

Open on both sides at the same time. E.g., N+ voltage-dependent channel =”voltage-gated”

Question 6

Carrier

Answer 6

Are not open on both sides at the same time, they change shape to let the molecule pass.

Question 7

Active transport

Answer 7

Membrane protein can transport molecules against their concentration gradient.

-These carriers (pumps) requires energy from:
1.The hydrolysis of ATP(primary active transport)
2.The potential energy stored in ionic gradients maintained by the cell (secondary active transport)

Question 8

Cotransporter

Answer 8

Secondary active transporter that can carry 2+ molecules at a time, one ion provides the energy (down its concentration gradient), while the other molecules is carried against.(cotransporter).

Question 9

Primary active transport

Answer 9

uses ATP as a source of energy

Question 10

Secondary active transport

Answer 10

use the potential energy stored in ionic concentration gradients