Opium and its derivatives, morphine and heroin, duplicate the action of which of the following?

• A. Serotonin
• B. Endorphins
• C. Melatonin
• D. Cortisol

Answer: (B)

Verified step by step guidance

1. Understand the context: Opium and its derivatives, such as morphine and heroin, are known to affect the brain's chemistry and influence mood and perception.
2. Identify the function of endorphins: Endorphins are neurotransmitters in the brain that act as natural painkillers and mood enhancers. They are released in response to stress or discomfort and help to alleviate pain and induce feelings of pleasure or euphoria.
3. Compare the effects: Opium and its derivatives mimic the effects of endorphins by binding to the same receptors in the brain, which leads to pain relief and feelings of euphoria, similar to the natural effects of endorphins.
4. Differentiate from other options: Serotonin, melatonin, and cortisol have different roles. Serotonin is involved in mood regulation, melatonin regulates sleep-wake cycles, and cortisol is a stress hormone. None of these directly duplicate the pain-relieving and euphoric effects of opium derivatives.
5. Conclude the comparison: Since opium and its derivatives mimic the action of endorphins by binding to the same receptors and producing similar effects, the correct answer is that they duplicate the action of endorphins.