Matching membrane molecule descriptions to carrier protein and glycolipid

Steps:

• X describes a non-polar lipid like cholesterol (C, H, O only, no hydrophilic part).
• Y describes an amphipathic lipid with a hydrophilic head (forms H-bonds with external water) and hydrophobic region inside, matching glycolipid structure.
• Z describes an integral protein with 1-2 hydrophobic transmembrane extensions, matching carrier protein function.
• Option D pairs Z as carrier protein and Y as glycolipid, aligning with definitions.

Why D is correct:

• Carrier proteins are transmembrane proteins with hydrophobic regions spanning the bilayer (Z); glycolipids are lipids with hydrophilic sugar heads extracellularly and hydrophobic tails embedded (Y).

Why the others are wrong:

• A: X is a non-polar lipid, not a protein.
• B: X is a non-polar lipid, not a protein.
• C: Y is a lipid, not a protein; X lacks a hydrophilic head.

Final answer: D