Membrane Transport

Front

What is active transport?

Back

Active transport is the movement of substances across a cell membrane against their concentration gradient, requiring energy (ATP).

Front

What is passive transport?

Back

Passive transport is the movement of substances across a cell membrane without the use of energy, moving down the concentration gradient.

Front

Define selectively permeable membrane.

Back

A selectively permeable membrane allows certain molecules to pass through while blocking others.

Front

What is facilitated diffusion?

Back

Facilitated diffusion is a type of passive transport that uses transport proteins to help move substances across a membrane.

Front

What is the sodium-potassium pump?

Back

The sodium-potassium pump is an active transport mechanism that moves sodium ions out of the cell and potassium ions into the cell, using ATP.

Front

What is endocytosis?

Back

Endocytosis is the process by which cells engulf substances from their external environment, bringing them into the cell.

Front

What is exocytosis?

Back

Exocytosis is the process by which cells expel materials to the outside environment, often using vesicles.

Front

What is osmosis?

Back

Osmosis is the diffusion of water across a selectively permeable membrane from an area of low solute concentration to an area of high solute concentration.

Front

What is a concentration gradient?

Back

A concentration gradient is the difference in the concentration of a substance across a space.

Front

What is the role of transport proteins?

Back

Transport proteins facilitate the movement of substances across a cell membrane, either passively or actively.