Question

1 multiple choice 5 points
long - term exposure to opioid drugs
has not been scientifically proven to cause damage to any tissue or organ system.
causes damage to the mesolimbic dopamine system.
is a common cause of kidney disease.
can weaken the heart.
2 multiple choice 5 points
heroin is more potent than morphine because
it is often injected instead of swallowed.
it more readily crosses the blood - brain barrier.
it is a natural opioid.
it is a synthetic opioid.
3 multiple choice 5 points
the two major active chemicals in opium are
morphine and codeine.
heroin and cocaine.
paregoric and laudanum.
meperidine and oxycodone.

Explanation:

• For the first question: Long - term opioid exposure is known to have various effects. While it may not be the most common cause of kidney disease compared to other factors like diabetes or hypertension, and it doesn't specifically target the mesolimbic dopamine system in the way some other drugs (like stimulants) do. However, opioids can have cardiovascular effects, and weakening the heart (e.g., through bradycardia in some cases and potential long - term hemodynamic changes) is a valid concern.
• For the second question: Heroin's greater potency is mainly due to its ability to cross the blood - brain barrier more readily than morphine. Injection vs. swallowing (route of administration) can affect onset but not the inherent potency difference. Heroin is a semi - synthetic opioid (derived from morphine), not a natural or purely synthetic opioid in the strictest sense.
• For the third question: Opium is the raw material from which many opioids are derived. Morphine and codeine are the two major active chemicals naturally present in opium. Heroin is a derivative of morphine, cocaine is a different class of drug (stimulant), paregoric and laudanum are opioid - containing mixtures, and meperidine and oxycodone are synthetic or semi - synthetic opioids not naturally present in opium.

Answer:

1. can weaken the heart.
2. it more readily crosses the blood - brain barrier.
3. morphine and codeine.