Cell Membrane and Passive Transport

Front

What is the main function of the cell membrane?

Back

The cell membrane regulates what enters and exits the cell, providing protection and support.

Front

Define passive transport.

Back

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

Front

What is simple diffusion?

Back

Simple diffusion is the process by which small or nonpolar molecules move directly through the phospholipid bilayer from an area of high concentration to an area of low concentration.

Front

What is facilitated diffusion?

Back

Facilitated diffusion is the process by which larger or polar molecules pass through the cell membrane via protein channels, moving from high to low concentration.

Front

What is osmosis?

Back

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

Front

What are phospholipids?

Back

Phospholipids are molecules that make up the cell membrane, consisting of a hydrophilic (water-attracting) head and two hydrophobic (water-repelling) fatty acid tails.

Front

What does selectively permeable mean?

Back

Selectively permeable means that a membrane allows certain substances to pass through while blocking others.

Front

What is the role of proteins in the cell membrane?

Back

Proteins in the cell membrane assist in transport, act as receptors, and provide structural support.

Front

What is the hydrophobic part of a phospholipid?

Back

The hydrophobic part of a phospholipid is the fatty acid tails, which repel water.

Front

What is the concentration gradient?

Back

The concentration gradient is the difference in the concentration of a substance across a space, driving the movement of molecules.