Cell Structure and Function

Which part of the cell wall is the first to develop in a growing plant cell?

• Secondary wall
• Middle lamella
• Tertiary wall
• Primary wall

What makes the cell membrane semi-fluid?

• Rigid protein scaffolding
• Solid phospholipid layer
• DNA strands within the membrane
• Lipid bilayer with mobile proteins

What is the function of the plasma membrane in secretion?

• Storing secretions
• Generating ATP
• Synthesizing hormones
• Transporting molecules out of the cell

How does the Na+/K+ pump maintain ion balance in cells?

• By letting ions diffuse freely
• By storing ions in vacuoles
• By blocking ion movement
• By transporting sodium out and potassium into the cell

What is the main difference between simple diffusion and facilitated diffusion?

• Facilitated diffusion requires ATP
• Simple diffusion uses proteins
• Facilitated diffusion uses carrier proteins
• They are the same process