3.2 Passive vs. Active Transport

Front

What is passive transport?

Back

Passive transport is the movement of substances across a cell membrane without the use of energy, relying on concentration gradients.

Front

What is active transport?

Back

Active transport is the movement of substances across a cell membrane using energy, often against a concentration gradient.

Front

Define hypertonic solution.

Back

A hypertonic solution has a higher concentration of solutes outside the cell than inside, causing water to move out of the cell.

Front

Define hypotonic solution.

Back

A hypotonic solution has a lower concentration of solutes outside the cell than inside, causing water to move into the cell.

Front

Define isotonic solution.

Back

An isotonic solution has equal concentrations of solutes inside and outside the cell, resulting in no net movement of water.

Front

What is diffusion?

Back

Diffusion is the process by which molecules spread from areas of high concentration to areas of low concentration.

Front

What is osmosis?

Back

Osmosis is the diffusion of water molecules across a selectively permeable membrane.

Front

What is endocytosis?

Back

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

Front

What is exocytosis?

Back

Exocytosis is the process by which cells expel substances by vesicles fusing 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.