Practice Questions

Immune cells use recognition markers to identify infected or foreign cells (e.g., pathogens).

Cholesterol is a steroid, characterized by its four-ring hydrocarbon structure.

Both facilitated and simple diffusion are passive processes driven by concentration gradients.

Peripheral proteins sit on the outside (or inside) surface of the bilayer.

Carrier proteins bind specific molecules and shift conformation to move them across the membrane.

The phosphate group is negatively charged and highly attracted to water.

Saturated chains pack tightly, resulting in a more rigid, less fluid membrane.

The cell membrane's surface markers are crucial for identifying "self" vs "non-self" cells.

Plasmalemma is essentially the plasma membrane of a cell.

Small, non-polar molecules move easily through the non-polar lipid bilayer.