Diffusion and Osmosis REVIEW

Front

What is facilitated diffusion?

Back

Facilitated diffusion is a process that moves substances across a cell membrane with the help of membrane proteins, down their concentration gradient, without using the cell's energy.

Front

What does it mean for a membrane to be selectively permeable?

Back

A selectively permeable membrane allows certain substances to pass through while blocking others, thus regulating the movement of materials in and out of the cell.

Front

What role do membrane proteins play in facilitated diffusion?

Back

Membrane proteins assist in the transport of molecules across the cell membrane during facilitated diffusion, enabling substances that cannot directly cross the lipid bilayer to enter or exit the cell.

Front

What is the difference between semi-permeable and impermeable membranes?

Back

A semi-permeable membrane allows some substances to pass through while blocking others, whereas an impermeable membrane does not allow any substances to pass through.

Front

What is passive transport?

Back

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

Front

What is osmosis?

Back

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

Front

What is the concentration gradient?

Back

The concentration gradient is the difference in the concentration of a substance across a space, which drives the movement of molecules from areas of high concentration to areas of low concentration.

Front

What is active transport?

Back

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

Front

What is the significance of the cell membrane in cellular processes?

Back

The cell membrane is crucial for maintaining homeostasis, protecting the cell, and regulating the movement of substances in and out of the cell.

Front

What is the difference between diffusion and facilitated diffusion?

Back

Diffusion is the passive movement of molecules from high to low concentration without assistance, while facilitated diffusion requires specific proteins to help transport molecules across the membrane.