Diffusion Through a Membrane

Front

What is diffusion?

Back

Diffusion is the process by which molecules move from an area of higher concentration to an area of lower concentration until equilibrium is reached.

Front

What is a selectively permeable membrane?

Back

A selectively permeable membrane allows certain molecules to pass through while blocking others, facilitating controlled diffusion.

Front

What factors affect the rate of diffusion?

Back

The rate of diffusion is affected by temperature, concentration gradient, size of molecules, and the nature of the medium.

Front

What is osmosis?

Back

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

Front

What is the role of the cell membrane in diffusion?

Back

The cell membrane regulates the movement of substances in and out of the cell, allowing for selective diffusion.

Front

What is the starch indicator used for?

Back

The starch indicator, iodine, is used to test for the presence of starch in a solution, turning blue-black in its presence.

Front

What does a positive test for glucose using Benedict's solution indicate?

Back

A positive test for glucose using Benedict's solution indicates the presence of reducing sugars, changing the solution from blue to green, yellow, or brick red.

Front

Why can't macromolecules diffuse through the cell membrane?

Back

Macromolecules are too large to pass through the small pores of the cell membrane, preventing their diffusion.

Front

What is equilibrium in the context of diffusion?

Back

Equilibrium is the state reached when the concentration of molecules is equal on both sides of a membrane, resulting in no net movement.

Front

What is facilitated diffusion?

Back

Facilitated diffusion is the process by which specific molecules are transported across a membrane via protein channels without energy expenditure.