Active Transport Introduction

Active Transport

• Definition: Active transport is a cellular process that moves molecules across a cell membrane against their concentration gradient, from a region of lower concentration to a region of higher concentration.
• Energy Requirement: Unlike passive transport, active transport requires energy. This energy is typically supplied by ATP (adenosine triphosphate).
• Metaphor (The Hotel Elevator):
  • Imagine an elevator in a hotel that requires a key card to operate. This represents active transport.
  • The act of entering and using the elevator is similar to molecules moving across a membrane.
  • The 'key card' is analogous to the ATP required for active transport, representing an extra step or requirement for the process to occur.
  • Contrast with Passive Transport: An elevator in a mall, which does not require a key card, can be compared to passive transport, where no extra energy (like ATP) is needed.