King Saud University
College of pharmacy 351 PHG Final exam (17.5 marks)
Pharmacognosy Department First semester 1428 Time : 50 minutes
Dr. Hanan Al.Yousef
All questions are to be attempted.
Question I: Read the following statements. Make (True) for the correct answer and (False) for the false one.
T.F. 1- C-glycosides are very stable (need oxidative hydrolysis).
T.F. 2- α and β sterio-isomers of the same glycoside are usually hydrolysed by the same enzyme.
T.F. 3- Glycosides can be precipitate by lead acetate.
T.F. 4- Glycosides are not reduced Fehling’s unless they are hydrolysable by enzymes or acids.
T.F. 5- Myrosin enzyme is specific for thioglycosides e.g., Sinigrin and Sinalbin.
T.F. 6- The saturation and/or cleavage of the lactone ring destroys the cardiac activity.
T.F. 7- The presence of tannins in senna makes the drug constipating.