[Campbell Biology P.188] A patient is diagnosed with familial hypercholesterolemia. Based on... | Practice Question

A patient is diagnosed with familial hypercholesterolemia. Based on the provided text, what is the most likely underlying cellular issue causing high cholesterol levels in their blood?

  • A: Defective or missing LDL receptor proteins on plasma membranes.
  • B: Overproduction of low-density lipoproteins (LDLs) by liver cells.
  • C: Inability of cholesterol to travel in the blood in particles.
  • D: Excessive exocytosis of cholesterol from cells into the blood.

Explanation

The text explicitly states that in familial hypercholesterolemia, LDLs cannot enter cells because the LDL receptor proteins are defective or missing. This prevents cells from taking up cholesterol from the blood, leading to its accumulation.