Q: About a patient receiving Cholestyramine (LM-12)



Cholestyramine is used to reduce serum cholesterol because of its ability to interfere with the enterohepatic circulation of bile salts in the feces. When this drug is prescribed to a patient, which of the following compounds will be found in high concentrations in feces?


a) Doxycholate


b) Palmitate


c) Glucuronate


d) Bilirrubin


e) Squalen


f) estercobilinogen


Q: About the Total Oxidation of a Fatty Acid (LM-11)





 The number of moles of reduced cofactors produced by the complete oxidation of 1 mol of capric acid to CO2 and water will be closest to which of the following?


a) 5 moles of  FADH2 and 10 moles of NADH.H+


b) 10 moles of  FADH2 and 10 moles of NADH.H+


c) 10 moles of  FADH2 and 15 moles of  NADH.H+


d) 10 moles of  FADH2 and 20 moles of  NADH.H+


e) 20 moles of  FADH2 and 20 moles of  NADH.H+





About Fat Mobilization

 Question About Lipid Metabolism (LM-10)

Which one of the following enzymes is involved in the mobilization of fatty acids from triacyglyerol stores in adipose tissue?


a)     carnitin acyl transferase


b)     gastric lipase


c)      hormone sensitive lipase


d)     lipoprotein lipase


e)     pancreatic lipase


f)       phospholipase A2


g)     phospholipase C








Some questions about Lipoproteins

(LM-06) This kind of lipoprotein is synthesized in the intestinal cells and releases fatty acids in muscle and adipose tissue.


a)     Chylomicrons

b)     HDL

c)      IDL

d)     LDL

e)     VLDL


(LM-07)Lipoprotein lipase acts in:


a)     Hydrolysis of triacylglycerols of plasma lipoproteins to supply fatty acids to various tissues.

b)     Intestinal uptake of dietary fat

c)      Intracellular hydrolysis of lipids from adipose tissue

d)     Hydrolysis of amino acids from lipoproteins

e)     Digestion of lipids contained in foods


(LM-08) This apoprotein is necessary for the activation of lipoprotein lipase:


a)     Apo A-I

b)     Apo A-II

c)      Apo A-IV

d)     Apo B-48

e)     Apo B-100

f)       Apo C-I

g)     Apo C-II

h)    Apo C-III

i)       Apo D

j)       Apo E




(LM-09) Fatty liver (hepatic steatosis) occurs in some conditions as obesity, uncontrolled diabetes mellitus and chronic ethanol ingestion, in which there is an imbalance between hepatic triacylglycerol synthesis and the secretion of the lipoproteins that transfer hepatic triacylglycerols and other lipids to peripheral tissues. These lipoproteins are:


f)     Chylomicrons

g)     HDL

h)     IDL

i)     LDL

j)     VLDL



Q LM-04: About a congenital disorder of lipid metabolism

Biochemistry Question LM-04





An adopted baby boy, (approximately 6-month-old), whose family history is unknown,  presents with dark greenish colored stools and excessive crying for four days. A physical examination of the child revealed a pallor skin with an enlarged liver and enlarged spleen.


Blood test reveals a lactescent  plasma and a lipid profile showed very high levels of triglycerides (2 500 mg/dL}. Lipoprotein electrophoresis demonstrated an abnormal extensive band of chylomicrons.  


Based in the information above, the most likely diagnosis for this patient is:


a)     Abetalipoproteinemia 


b)     Familial defective Apoprotein B


c)      Familial hypercholesterolemia


d)     Lipoprotein Lipase Deficiency


e)     Sphingolipidosis



Q: About a patient with Gaucher disease

Question about Lipid Metabolism (LM-03)


                                           autosomal recessive disorder wikipedia


A Russian Jewish mother presents to your office with a very pale child. The physical exam shows massively enlarged liver and spleen and extensive skeletal disease. Lab exams show anemia and low blood platelets.


Because of your findings and the fact that the child is an Ashkenazi Jewish girl, you suspect it could be a Gaucher Disease, so you refer the patient for a liver biopsy.


You expect that the results of the biopsy will confirm your diagnosis of this autosomal recessive disorder, and thus, it will  show an accumulation of sphingolipids in liver cells, as a consequence of a deficit of :


a)     a cytosol enzyme


b)     a lipoprotein lipase


c)      a liver hormone sensitive lipase


d)     a lysosomal enzyme


e)     a mitochondrial enzyme


f)       a peroxisomal enzyme




Q LM-05 About chest pain and xanthomas


                                             cholesterol structure 



A.W. is a 35-year-old male admitted to a hospital with chest pain.  On admission to the E.R. physical examination revealed tendinous xanthomas of the 2nd through 5th digits bilaterally.  Non-fasting lipid profile revealed :


            -Total cholesterol (TC): 310 mg/dL (Normal up to 200 mg/dl)



            -Low-density lipoprotein cholesterol (LDL-C): 237 mg/dL (100 – 190 mg/dl)



            -High-density lipoprotein cholesterol (HDL-C): 36 mg/dL (30 – 60 mg/dl)



            -Triglyceride (TG): 185 mg/dL (< 180 mg/dl)


He has a strong family history of cardiovascular disease (CVD). Screening lipid profiles of AW’s children reveal altered lipid patterns. Based on family history, lipid profile, and clinical observation,


I- Which is your diagnosis for this patient?


a)     Lipoprotein Lipase Deficiency


b)     Abetalipoproteinemia


c)      Sphingolipidosis


d)     Familial hypercholesterolemia


e)     Disbetahyperlipoproteinemia (Type III hyperlipidemia}



II.- Which is the biochemical alteration that causes this disease?


      a)     a mutation in LDL receptors


b)     a defective apoprotein B


c)      a deficit of Lipoprotein lipase


d)     a deficit of Apo C-II


e)     a deficit of cholesterol esterase