Active transport

Question 1

What is active transport?

Answer 1

Active transport is the movement molecules/ions into or out of a cell from a region of lower concentration to a region of higher concentration by using ATP and carrier proteins

Question 2

What two components facilitate active transport?

Answer 2

ATP and carrier proteins are used to facilitate active transport for ions/molecules

Question 3

What is ATP used for in active transport?

Answer 3

ATP is used to directly move the molecules, individually moving molecules using a concentration gradient set up by active transport

Question 4

How is active transport different from passive transport? (4pts)

Answer 4

1* Active transport needs metabolic energy in the form of ATP

2* In active transport, substances are moved against a concentration gradient

3* Carrier proteins, which act as a pump, are involved in active transport

4* Active transport is a selective process, that only allows specific substances to be transported

Question 5

What is the process of the active transportation of a single molecule/ion? (6pts)

Answer 5

1* Firstly, carrier proteins spanning the plasma membrane, bind to a molecule/ion to be transported from one side to another

2* The molecule/ion binds to receptor sites on carrier proteins

3* Inside of the cell, the ATP binds to the protein causing it to split into ADP and a phosphate molecule

4* This results in the protein molecule changing shape and opening the opposite side of the membrane

5* The molecule/ion is then released to the other side of the membrane

6* The phosphate molecule is then released from the protein causing it to revert to its original shape and repeat the process

Question 6

What is a similarity between active transport and facilitated diffusion?

Answer 6

Active transport and facilitated diffusion are similar because both use carrier proteins during the processes

Question 7

What are the differences between active transport and facilitated diffusion? (2pts)

Answer 7

1) Facilitated diffusions occurs down a concentration gradient whilst active transport occurs against a concentration gradient

2) Facilitated diffusions does not require metabolic energy whilst active transport requires metabolic energy

Question 8

Does active transport always involve molecules moving in the same direction in/out?

Answer 8

No, active transport can have one molecule or ion move into the cell/organelle at the same time as a different one is being removed

Question 9

What is an example of molecules/ions being actively transported into and out of the cell/organelle?

Answer 9

The sodium/potassium pump

Question 10

Describe the process of the sodium/potassium pump:

Answer 10

In the sodium - potassium pump, sodium ions are actively transported out of the cell/organelle whilst potassium ions are actively transported into the cell from the surroundings