This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
[{'content': 'Squalene is the intermediate product during synthesis of: \nSelect and explain. \nA. VLDL, B. Cholesterol, C. Tachysterol, D. Lonosterol', 'role': 'user'}, {'content': "Answer: B \nExplanation: Squalene is formed from six isoprenoid units. It cyclizes to give rise to parent steroid ionosterol from which cholesterol is formed. Must Know: The biosynthesis of cholesterol may be divided into five steps: (1) Synthesis of mevalonate from acetyl-CoA ; (2) Formation of isoprenoid units from mevalonate by loss of CO2 ; (3) Condensation of six isoprenoid units to form squalene ; (4) Cyclization of squalene give rise to the parent steroid, lanosterol. (5) Formation of cholesterol from lanosterol. Ref: Botham K.M., Mayes P.A. (2011). Chapter 26. Cholesterol Synthesis, Transpo, & Excretion. In D.A. Bender, K.M. Botham, P.A. Weil, P.J. Kennelly, R.K. Murray, V.W. Rodwell (Eds), Harper's Illustrated Biochemistry, 29e.", 'role': 'assistant'}]