Chapter 5: The Dynamic Cell - Active Transport Mechanisms

Vocabulary flashcards for reviewing active transport mechanisms from the lecture notes.

Active Transport

Energy (ATP) required to move molecules across the cell membrane.

Primary Active Transport

Directly uses ATP to move ions across a membrane, creating a charge difference.

Secondary Active Transport

Does not directly use ATP; relies on the electrochemical gradient established by primary active transport.

Co-transport

Movement of a substance due to the electrochemical gradient established by primary active transport.

Electrical Gradient

Difference in charge across the plasma membrane.

Electrochemical Gradient

Combined concentration gradient and electrical charge that affects an ion.

Pumps (in Active Transport)

Cells expend energy to move molecules against a concentration gradient, requires transport protein and ATP.

Uniporter

Carries one specific ion or molecule.

Symporter

Carries two different ions or molecules, both in the same direction.

Antiporter

Carries two different ions or molecules, but in different directions.

Sodium-Potassium Pump

Active transport protein that pumps sodium ions (Na+) out of cells and potassium ions (K+) into cells, using ATP.

Co-transport

Active transport of a solute indirectly drives transport of other solutes.

Bulk Transport

Cells take in or expel larger molecules and particles via vesicle formation.

Endocytosis

Cell's plasma membrane invaginates, forming a pocket around the target particle; movement into cell.

Phagocytosis

Cell takes in large particles or other cells.

Pinocytosis

Takes in molecules, including water, which the cell needs from the extracellular fluid; cellular drinking.

Receptor-Mediated Endocytosis

Uses receptor proteins in the plasma membrane to target specific substances for uptake.

Exocytosis

Expels material from the cell into the extracellular fluid.