In the process of albumin synthesis, carbohydrate chains that will be eventually transferred to the protein component of albumin are synthesized on which of the following substrate molecules?

A. Arachidonic acid
B. Ceramide
C. Dermatan sulfate
D. Dolichol
E. Hyaluronic acid

The correct answer is D. In the synthesis of glycoproteins (which are mostly protein with some attached sugars), the very long, phosphated lipid, dolichol, serves as the substrate for forming the branched carbohydrate "trees" that are then transferred to proteins. This process occurs on the rough endoplasmic reticulum, and the resulting glycoproteins are then transferred to the Golgi complex for further processing before incorporation into the plasma membrane, transfer to lysosomes, or release as a secreted protein.
Arachidonic acid (choice A) should be remembered as the precursor of prostaglandins, thromboxanes, and leukotrienes.

Ceramide (choice B) is the lipid precursor to which sugars are added to form gangliosides and galactocerebrosides.

Dermatan sulfate (choice C) is a glycosaminoglycan chain that helps form proteoglycans, not glycoproteins.

Hyaluronic acid (choice E) is a glycosaminoglycan chain that helps form proteoglycans, not glycoproteins