Practice Questions

Robertson used electron microscopy to observe the "railroad track" appearance of membranes, implying three distinct layers.

Glycoproteins are proteins covalently bonded to carbohydrate chains, playing key roles in cell-cell recognition.

Active transport moves solutes against their concentration gradient, which is an endergonic process requiring ATP.

The Fluid Mosaic Model dictates that proteins can move laterally within the plane of the lipid bilayer.

Cholesterol acts as a temperature buffer, preventing excessive fluidity at high temperatures and excessive rigidity at low temperatures.

The double bonds in unsaturated fatty acids create "kinks" that prevent tight packing, maintaining fluidity at low temperatures.

The hydrophobic core of the phospholipid bilayer prevents the free passage of polar/charged molecules.

The mosaic aspect describes the heterogeneous arrangement of proteins scattered throughout the phospholipid bilayer.

Distraction is the enemy of effective scanning.

You cannot read everything; you must select what matters.