Cell Structure and Function

Which of the following is true about the fluid mosaic model?

• Proteins are immobile
• The membrane is solid
• All proteins span the entire membrane
• Proteins float in a fluid bilayer and can move laterally

What is the main reason why facilitated diffusion is still considered passive transport?

• It uses ATP
• It moves ions only
• It uses vesicles
• No energy is used despite moving against a gradient locally

What is the role of the cell wall in preventing excessive water uptake?

• Absorbs excess water
• Breaks down water molecules
• Repels water molecules
• Provides physical resistance

What happens to a cell placed in an isotonic solution?

• It bursts
• It shrinks
• It divides rapidly
• There is no net movement of water

What is the main difference between osmosis and diffusion?

• Osmosis requires energy
• Osmosis moves ions only
• Osmosis moves against the gradient
• Osmosis involves only water movement