active and passive transport

Front

What is active transport?

Back

Active transport is the movement of molecules across a cell membrane from a region of lower concentration to a region of higher concentration, requiring energy (ATP).

Front

What is passive transport?

Back

Passive transport is the movement of molecules across a cell membrane without the use of energy, occurring along the concentration gradient.

Front

What is osmosis?

Back

Osmosis is the diffusion of water molecules across a semipermeable membrane from an area of high water concentration to an area of low water concentration.

Front

What is diffusion?

Back

Diffusion is the net movement of molecules from an area of high concentration to an area of low concentration until equilibrium is reached.

Front

What is facilitated diffusion?

Back

Facilitated diffusion is a type of passive transport that uses transport proteins to help move molecules across the cell membrane without energy.

Front

What is endocytosis?

Back

Endocytosis is the process by which cells absorb external substances by engulfing them in a membrane.

Front

What is exocytosis?

Back

Exocytosis is the process by which cells expel materials in vesicles that fuse with the cell 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 against their concentration gradients.

Front

What is concentration gradient?

Back

A concentration gradient is the difference in the concentration of a substance across a space, which drives diffusion.

Front

What is a semipermeable membrane?

Back

A semipermeable membrane is a barrier that allows certain substances to pass through while blocking others.