Unit 5 Terpenes Quiz - Online Quiz answers PDF

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Unit 5 – Terpenes Question 1 The terpene menthone exists as eight stereoisomers.

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False

Question 2 Infrared (IR) spectroscopy is used to identify functional groups in terpenes.  True Question 3 One mole of beta carotene is broken down metabolically to give two moles of vitamin A.  True Question 4 Which of the following is a bicyclic monoterpene?  -pinene Question 5 A triterpene contains three isoprene units.  False Question 6 Which vitamin is formed by oxidative metabolism of carotenes?  A1 Question 7 Carotenes are examples of terpenes which contravene the isoprene rule.  True

Question 8 How many stereoisomers would you expect of the following compound? (Hint: draw out the structure showing carbon and hydrogen atoms.)

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8

Question 9 Which of the following compounds are precursors or intermediates in the biosynthesis of terpenes and carotenes? Isoprene, acetyl coenzyme A, mevalonic acid, arachidonic acid.  Acetyl coenzyme A and melvalonic acid Question 10 One mole of beta carotene is broken down metabolically to give two moles of vitamin A.

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True

Question 11 Which of the following terpene skeletons does not obey the isoprene rule?

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B

Question 12 Which of the following is a cyclic monoterpene occurring in peppermint oil?  menthol Question 13 Terpenes are formed from isopentenyl pyrophosphate (IPP) which is itself formed from isoprene and ATP.  False Question 14

Essential oils contain chiefly mono- and sesquiterpenes  True Question 15 The geometrical (cis-trans) isomers of terpenes show optical rotations which are equal in magnitude but opposite in sign.  False Question 16 Which of the following compounds is a pigment in red peppers?  capsanthin Question 17 Which terpene is an allelochemical inhibiting the growth of bacteria on the surface of pine trees?  -pinene Question 18 Which of the following are recruiting pheromones for honeybees?  citral Question 19 A terpene with the molecular formula C15H24 absorbs 3 molecules of hydrogen to form a saturated hydrocarbon, C15H30. How many double bonds and rings are present in the terpene?  3 double bonds, 1 ring Question 20 Grandlure is an aggregation pheromone for ants.  False...