Note to Educators:
The Botany of Desire examines
the human desire to alter consciousness by telling the story of cannabis,
which is one of several psychoactive plants that affect our brains.
This lesson focuses on another of those plants, the opium poppy, and
explores the molecular structures of some of the drugs that are derived
from it, such as morphine and codeine, or synthesized in labs. These
drugs, which are regulated as controlled narcotics by the federal government,
provide people who are sick or injured with effective pain relief, but
can also lead to addiction. The purpose of this lesson is to provide
tools that can help students better understand what happens when psychoactive
plants alter the brain, and how the chemical compounds in those plants
produce their effects. It also provides an opportunity and a forum for
students to consider the consequences of intoxication. This subject
of drugs and their mind-altering affects is clearly a sensitive and
controversial one, not only for students but also for parents and other
stakeholders in education. Therefore, we urge you to consider carefully
the appropriateness of using this lesson plan in your school and community,
and to have whatever discussions may be necessary before doing so.
"In every culture and in every age of history, an enormous amount of human energy has gone into the production, distribution and consumption of psychoactive plants."
– Dr. Andrew Weil in The Botany of Desire
In every society except the
Inuit, whose climate is too harsh for vegetation, people have sought
to change the way they experience the world by using a variety of mind-altering
plants. Some of them, such as coca, poppy, and cannabis, are considered
intoxicating because they can cause profound changes to our consciousness.
Other plants that yield psychoactive products (products that affect
the mind or behavior), like coffee, tobacco and tea, affect our thoughts
and perceptions in subtler ways. The relationships between these various
plants and the people who use them have evolved over time, both influencing
and reflecting the values of the societies in which they are used. And
all of these plants contain molecules that cause changes to the biochemical
processes that go on deep inside our brains.
The opium poppy and the family of drugs that can be made from it present humanity with a paradox. Because of their remarkable effectiveness at relieving pain, opiates are a shining example of the good that plant drugs can do for us. But, unfortunately, opiate use can turn people into drug addicts. Opiates actually mimic chemicals produced by the brain. While the human body can tolerate these substances in low doses, our system cannot handle higher doses without extreme changes in biochemistry that ultimately lead to craving for them.
Opium itself is a resin that's
naturally produced by the seedpods of a species of poppy flower called
Papaver somniferum. In the early 19th century, a German
scientist discovered the chemical that is opium's primary active ingredient.
He named it morphine, after Morpheus, the Roman God of dreams, because
it is so effective at inducing sleep. Morphine is also one of the most
effective painkillers ever discovered. But doctors and patients soon
realized that some people become addicted to morphine. In the late 19th
century, scientists developed a chemical variant of morphine that they
thought would be less addictive. It is called diacetylmorphine — but
it is better known as heroin. Unfortunately, the scientists were wrong,
and heroin turned out to be even more addictive than morphine. These
two chemical cousins show how powerfully the molecules found in the
opium poppy plant can alter what goes on in the human mind.
This lesson consists of two
distinct and complementary parts. First, using movie clips from The Botany of Desire and then the online interactive feature
Altering Consciousness, students will study the background science
about these mind-altering plants. Next, students will explore the molecular
structures of several of the drugs derived from plants, learn about
their physiological effects on humans, and explore their portrayals
in popular culture. Finally, using gumdrops and toothpicks, students
will build several models of alkaloid compounds. These models will show
how the number and position of carbon, hydrogen, and oxygen atoms on
a benzene ring are all that separates one opiate compound from a close
chemical relative that is more or less psychoactive.
This lesson is an opportunity
to explore the connections between chemistry, culture, and anthropology.
Both the film and the interactive web feature provide useful background
information to help frame the students' exploration.
Science National Content Standard 1: Science as Inquiry
Science National Content Standard 2: Physical Science
As a result of their activities in grades 9-12, all students should develop an understanding of:
Science National Content Standard 5: Science and Technology
As a result of activities in grades 9-12, all students should develop:
Science National Content Standard 7: History and Nature of Science
As a result of activities in grades 5-8, all students should develop understanding of:
120 – 150 minutes
The following background information on the opium poppy provides some context for this lesson. One of the oldest known pain remedies, opium, a resin that can be harvested from a particular species of the poppy plant, originated in the Fertile Crescent region, bordered on the east by the Tigris/Euphrates River basin and on the west by the Mediterranean Sea. A 6,000 year-old Sumerian text refers to the powerful little poppy.
In Homer's classic Greek epic The Odyssey, Helen spikes the wine of a grieving son with opium, suggesting that opium was also used as a remedy for depression.
In the early 19th century, a German scientist discovered morphine – the chemical that is the principal active ingredient in opium. Morphine has a much stronger effect on the brain than does raw opium and soon became one of medicine's most relied-upon painkillers. It also became a widely used treatment on battlefields, to soothe the excruciating pain of wounded soldiers. But morphine also has a dark side: it makes many of its users into addicts. Those who took it over a sustained period found it very difficult to stop. If they tried to wean their bodies off the drug, they would become sick with chills, shakes and nausea – symptoms that would dramatically ease if they started using morphine again. The social and political battles over opium, and the drugs that can be made from it, stem from its dual nature as a pain reliever and cause of addiction. Between 1839 and 1842, Great Britain and China fought a war over opium. China had tried to halt the trade of the drug, which had made addicts of many of its citizens.
Scientists developed other pain-killing drugs from opium, such as codeine, which, like morphine, can be isolated directly from opium resin. Around the turn of the 20th century, the German pharmaceutical company Bayer brought to market a new opium derivative: heroin. First synthesized from morphine in 1874, heroin was thought to be (and was marketed as) less addictive than morphine. But by 1910, studies showed that heroin was not only no less addictive, but also faster acting and more powerful.
As scientists learned more about the ability of poppy-derived opiate drugs to treat pain, governments around the world began controlling these drugs more strictly. Nonetheless, during the 20th century, heroin became a popular recreational drug in many countries. Its use led to the deaths of celebrities such as Janis Joplin in 1970 and John Belushi in 1982.
Today, opium poppies are grown mainly in the "Golden Triangle" region of Southeast Asia (Myanmar/Burma, Thailand, and Laos) and in Afghanistan.
(Sources: Napoleon's Buttons: 17 Molecules That Changed History by Penny Le Couteur and Jay Burreson; www.pbs.org/wgbh/pages/frontline/shows/heroin/etc/history.html; opiates.net/)
Image source: upload.wikimedia.org/wikipedia/commons/6/62/Morphine-from-xtal-3D-balls.png (Creative Commons)
The structures of morphine, codeine, and diacetylmorphine (heroin) are very similar, but the physiological effects of each of these molecules are different. Compare morphine to heroin and codeine. Heroin has a CH3COO group that replaces the HO of morphine and codeine has a CH3O that replaces the HO of the morphine at the upper left of the molecule.
Interactive Molecular Model online
Morphine (requires Java and/or
CHIME plug in)
The Physiological Effects
C17H19NO3 is a highly potent opiate used for pain relief. It is the principal active agent in opium. Like other opiates, such as diacetylmorphine (heroin) and the milder pain reliever codeine, morphine acts directly on the central nervous system.
Morphine blocks pain receptors inside the brain, changing how it responds to pain messages traveling to it along nerve pathways from other parts of the body. In addition to euphoria and pain relief, morphine can also cause serious side effects such as nausea, constipation, and confusion. It can also cause addiction, inhibit respiration, and lead to unconsciousness, coma, and even death. Morphine is a powerful and dangerous substance.
After an intravenous injection of heroin, users report feeling a surge of euphoria ("rush") accompanied by dry mouth, a warm flushing of the skin, heaviness of the extremities, and clouded mental functioning. Following this initial euphoria, the user goes "on the nod," an alternately wakeful and drowsy state. Users who do not inject the drug may not experience the initial rush, but other effects are the same.
With regular heroin use, tolerance develops, in which the user's physiological (and psychological) responses to the drug decrease and more heroin is needed to achieve the same intensity of effect. Heroin overdoses frequently involve a suppression of respiration. Heroin users are at high risk for addiction. The NIH's National Institute on Drug Abuse estimates that about 23 percent of individuals who use heroin become dependent on it. Heroin can also cause serious side effects such as nausea, constipation and confusion. It can also lead to unconsciousness, coma, and even death.
Codeine is used medically to relieve moderate pain and suppress coughs. Codeine increases tolerance to pain, decreasing discomfort, but the pain remains apparent to the patient. In addition to reducing pain, codeine causes drowsiness and depresses breathing. Compared to morphine, codeine produces less analgesia (pain relief), sedation, and respiratory depression, and is usually taken orally.
In addition to euphoria and pain relief, codeine can also cause side effects such as nausea, constipation, confusion, unconsciousness, coma, and even death. Although not as addictive as heroin, sustained use of codeine can lead to addiction.
For more information on the effects of these drugs, visit the following sites:
PART 1: INTOXICATION DISCUSSION (25 – 30 minutes)
In the film, scientists assert that human beings have an innate drive to experience other states of consciousness. Do you agree? If so, why do you think that is? How do we most commonly explore altered mental states? What evolutionary benefits do you think there might be to this drive?
Which drugs are tolerated in particular cultures? How have drugs been used in various cultures? How was cannabis used in the United States in the 19th century?
What is the psychoactive molecule found in marijuana and what does it do to the brain?
Why is forgetting important to the normal functioning of the brain? Part of the value of sleep is that it gives the brain an opportunity to process and organize the day's experiences – retaining some and discarding others. How does this understanding of sleep expand on the notion that forgetting can be good?
PART 2: INQUIRY PATH (10 – 15 minutes)
PART 3: MOLECULAR RESEARCH & PRESENTATION (50 – 75 minutes)
Note to Teachers: This section makes use of the Altering Consciousness web interactive available at www.pbs.org/thebotanyofdesire/altering-consciousness.php. Take some time to go through the interactive and familiarize yourself with its content, as it contains much of the information referenced in the lesson steps below.
PART 4: MODEL BUILDING (15 – 20 minutes)
Note: The Altering Consciousness web interactive will, once again, be a useful resource for this modeling activity.
Option 1: Evaluate the group presentations and the models of molecules on the basis of achieving the objectives of the lesson.
Option 2: Discussion or essay questions
Ask your students the following questions. Then, discuss their answers or have them submit them in writing.