Diffusion and Cell Membrane Concepts

This video tutorial explains diffusion, a process where particles move from high to low concentration until evenly distributed. It uses a beaker example to illustrate equilibrium and constant particle motion. The concept is applied to cells, highlighting the semi-permeable membrane's role in diffusion. The tutorial discusses concentration gradients and provides examples like oxygen and carbon dioxide diffusion in red blood cells. Diffusion is passive, requiring no energy, unlike active processes.

What is the basic principle of diffusion?

• Particles move randomly without any pattern.

• Particles remain stationary.

• Particles move from low to high concentration.

• Particles move from high to low concentration.

In the beaker example, what is the state called when particles are evenly distributed?

• Balance

• Inertia

• Equilibrium

• Stasis

What characteristic of the cell membrane allows certain particles to pass through?

• Impermeability

• Permeability

• Non-permeability

• Semi-permeability

Which factor does NOT affect a particle's ability to move across a cell membrane?

• Size

• Charge

• Color

• Lipid solubility

What is a concentration gradient?

• A difference in particle color

• A difference in concentrations across a space

• A difference in particle charge

• A difference in particle size

How do oxygen and carbon dioxide move in and out of red blood cells?

• By osmosis

• By active transport

• By facilitated diffusion

• By diffusion

What is the net movement of particles during diffusion?

• From low to high concentration

• From high to low concentration

• No net movement

• Random movement

What type of process is diffusion?

• Passive

• Static

• Energetic

• Active

Which process requires energy: diffusion or active transport?

• Neither

• Active transport

• Both

• Diffusion

What is the main difference between diffusion and active transport?

• Diffusion requires energy, active transport does not.

• Active transport requires energy, diffusion does not.

• Both require energy.

• Neither require energy.