Exploring Passive Transport Mechanisms

The video tutorial covers passive transport mechanisms in cells, including simple diffusion, osmosis, and facilitated diffusion. It explains how substances move across cell membranes without energy, driven by concentration gradients. The tutorial also discusses the concepts of isotonic, hypertonic, and hypotonic solutions, and how they affect cells. Facilitated diffusion is highlighted as a process involving protein channels to assist larger molecules in crossing the membrane.

What is a key characteristic of passive transport?

• It requires ATP.

• It involves the use of vesicles.

• It moves substances from low to high concentration.

• It moves substances from high to low concentration.

Which of the following is an example of passive transport?

• Active transport

• Exocytosis

• Endocytosis

• Simple diffusion

What happens to particles during diffusion?

• They move randomly but tend to spread from high to low concentration.

• They move from an area of low concentration to high concentration.

• They require energy to move.

• They stop moving once equilibrium is reached.

What is equilibrium in the context of diffusion?

• When particles stop moving.

• When particles require energy to move.

• When particles are evenly distributed throughout a space.

• When particles move from low to high concentration.

What is osmosis?

• The movement of large molecules through a membrane.

• The movement of particles using energy.

• The movement of solutes from high to low concentration.

• The movement of water across a semi-permeable membrane.

What does a hypertonic solution do to a plant cell?

• Makes it swell.

• Makes it shrivel.

• Keeps it the same size.

• Bursts it.

What happens to blood cells in a hypotonic solution?

• They become plasmalized.

• They remain the same.

• They shrivel.

• They swell and may burst.

What is facilitated diffusion?

• The movement of water through a membrane.

• The movement of particles using energy.

• The movement of large molecules through a channel protein.

• The movement of solutes from low to high concentration.

What role do channel proteins play in facilitated diffusion?

• They use energy to move particles.

• They create a hollow passage for large molecules.

• They stop particles from moving.

• They move water across the membrane.

What is the main difference between passive and active transport?

• Passive transport requires energy, active transport does not.

• There is no difference.

• Passive transport moves substances from high to low concentration without energy, active transport requires energy.

• Active transport moves substances from high to low concentration, passive transport does the opposite.