Practice Questions

Simple diffusion occurs directly through the lipid bilayer for small, non-polar molecules.

Lipids can self-seal due to the hydrophobic effect, reforming the bilayer automatically.

Cholesterol intercalates between the fatty acid tails, stabilizing the membrane.

Plasmalemma is a biological synonym for the plasma membrane.

High heat increases the kinetic energy of lipid tails, increasing the membrane's fluidity.

The Na+/K+ pump moves ions against their gradients using ATP, defining it as active transport.

Amphipathic molecules are essential for forming the bilayer as they interact with both aqueous and non-aqueous environments.

Transmembrane pumps (like the Na+/K+ pump) use ATP to change conformation and transport ions.

Transmembrane proteins are a subset of integral proteins that traverse both leaflets of the bilayer.

Glycoproteins and glycolipids act as cellular "identity tags" and mediate cell-cell adhesion.