- Active transport moves solutes against their concentration gradient using energy (ATP).
- The sodium-potassium pump is a common example, moving sodium out and potassium into the cell.
- This pump helps maintain the membrane potential, with the inside of the cell being negatively charged.
- Ions are driven across membranes by both a chemical force (concentration gradient) and a voltage gradient.
- Together, these forces form an electrochemical gradient.
- Endocytosis and exocytosis are forms of bulk transport requiring ATP.
- Pinocytosis engulfs fluids; phagocytosis takes in large particles; receptor-mediated endocytosis targets specific molecules.
- Exocytosis expels molecules from the cell, acting as the reverse of endocytosis.
Parent Tip: Review the logic above to help your child master the concept of active transport worksheet answers.
