Question

Which of the following are alkaloids?
A. Cellulose
B. Codeine
C. Morphine
D. Both B and C

Answer 1

Hint: Alkaloids have diverse and important physiological effects on human beings and on other animals. Some common alkaloids are morphine, strychnine, quinine, ephedrine and nicotine.
Alkaloids are found primarily in the plants and are especially common in the certain families of the flowering plants.

Complete step by step answer: Both codeine and morphine are alkaloids. Alkaloids are basic, naturally occurring organic compounds that contain one nitrogen atom in its chemical structure. It also includes some related compounds with neutral and weakly acidic properties. In addition to carbon, hydrogen and nitrogen, alkaloids may also contain oxygen, sulfur and other elements such as chlorine, bromine, and phosphorus. Some synthetic compounds that share a similar structure to alkaloids may also be termed as alkaloids.
i. Codeine: Codeine is the naturally occurring phenanthrene alkaloid that has analgesic, antidiarrheal and antitussive activities. Codeine mimics the action of endogenous opioids by binding to the opioid receptors at many sites within the central nervous system (CNS).
ii. Morphine: Morphine is a medication obtained from the plant that belongs to the opiate family. It also occurs naturally in a number of plants and animals, including humans. It acts directly on the central nervous system of the brain and decreases the pain.
Hence, the correct answer is option D.

Note: Alkaloids act as local anaesthetics, for example; cocaine to treat fibrillation, quinidine, act as anti-tumour agents, quinine as antibacterials, emetine as a pain killer. The nicotine is an unusual alkaloid. It has two nitrogen-containing heterocycles, pyridine and pyrrolidine. In pure form, most alkaloids are colourless, non-volatile and crystalline solids.