4.4 Active transport

Question 1

Define active transport.

Answer 1

The movement of molecules or ions into or out of yourself in the region of lower concentration to a higher concentration, using ATP and carrier proteins.

Question 2

How does active transport differ from passive forms? (4)

Answer 2

• metabolic energy in form of ATP needed
• substances are moved against a conc. gradient
• carrier protein involved, acts as a ‘pump’
• process is very selective

Question 3

Name an example of a pump that uses active transport.

Answer 3

Sodium-potassium pump