Unit 2 · 2.5 — Membrane Transport [cite: 9, 28]

Everything to learn here

• Concept: Passive transport represents the net movement of molecules down their concentration gradient without the input of metabolic energy [cite: 13, 14].
• Concept: Active transport requires a direct input of ATP energy to force molecules to move against their natural concentration gradient [cite: 13, 14, 15].
• Vocabulary: Exocytosis — bulk transport where internal cellular vesicles fuse with the plasma membrane to secrete large macromolecules outward [cite: 13, 14].
• Vocabulary: Endocytosis — bulk transport where the cell takes in macromolecules by engulfing them in new vesicles formed from the plasma membrane (includes phagocytosis and pinocytosis) [cite: 13, 14].
• Skill: FRQ Task Verb "Explain" — Explain why a specific transport scenario requires an input of ATP based on the directionality of the concentration gradient [cite: 16, 17].
• Concept: Explain how organisms utilize passive and active transport to maintain proper solute and water balance.
• Concept: Explain how endocytosis and exocytosis use energy to transport large quantities of materials via vesicles.

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