D.5+Stimulants

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** D.5 Stimulants **

**D.5.1 **
** List the physiological effects of stimulants**

**Stimulants** The picture at right shows an artists version of the synaptic cleft between two neurons. The pinkish objects are intended to represent the chemical neurotransmitters which act as messengers, relaying information from neuron to neuron.
 * Drugs that alter the levels of neurotransmitters, chemicals which tell the nervous system to stimulate the speed at which information is transmitted between neurons.
 * Cause an increased state of mental awareness and alertness by stimulating the brain and central nervous system.
 * Act as opposites to depressants (which reduce a person's state of mental awareness.
 * Examples: amphetamines, epinephrine (adrenaline), nicotine, and caffeine
 * Physiological effects:**
 * increase in heart rate and blood pressure
 * constriction of arteries
 * relaxation of air passages therefore an increase breathing rate (treatment of respiratory infections such as bronchitis)[[image:http://biotech.stofair.se/common/archive/images/26080.gif align="right" caption="Image from: biotech.stofair.se"]]
 * dilation of pupils
 * sweating
 * reduced appetite (treatment for obesity)
 * Increase concentration
 * Other long term side effects:**
 * emotional instability or depression
 * restlessness
 * sleeplessness
 * delusions and hallucinations

 **D.5.2 **    **Comparison of the Structures (similarities and differences)** > > **D.5.3 ** <span style="color: rgb(0, 0, 255);">**Discuss** **the short and long term effects of nicotine consumption** > <span style="color: rgb(255, 0, 0);">  The following blogs look at <span class="wiki_link_ext">opposing viewpoints on whether [|smoking is harmful or harmless] and whether [|smoking should be banned from public places].
 * Compare amphetamines and epinephrine (adrenaline)**
 * Physiological Similarities**
 * Increase physical energy by: 1) Increasing heart rate and blood pressure. 2) Increasing blood flow to the brain and muscles. 3) Increasing air flow to the lungs
 * Increase mental awareness; trigger the "fight or flight" syndrome
 * Dilation of the pupils
 * Reduce appetite
 * induce a sense of euphoria
 * Both can lead to the rapid development of both tolerance and dependence (addiction),
 * Both can have serious long-term effects if abuse/over used - depression and reduced resistance to infection. Abuse of amphetamines through overuse is a serious problem.
 * Physiological Differences**
 * epinephrine (adrenaline) is regulated/produced naturally by the brain
 * amphetamines are synthetic drugs
 * sympathomimetic
 * Sympathiometic drugs**
 * Mimic the effects of naturally produced epinephrine (adreneline)
 * speeds up heart rate
 * increases sweat production
 * increases breathing rate
 * examples: nicotine, amphetamine, methamphetamine, speed, ecstasy
 * Both based on the phenylethylamine structure
 * Both have a benzene (aromatic) ring with a hydrocarbon chain containing an amine.
 * Primary amine (1 C atom attached to N atom) in amphetamine and secondary amine (2 C atoms attached to N atom), NH in epinephrine.
 * Epinephrine has three hydroxy (-OH) groups while amphetamine has none.[[image:AMPHETHAMINE.jpg width="319" height="204" align="right" caption="amphetamine"]]
 * Nicotine is obtained from tobacco plants but is also found at low concentrations in tomato, potato, eggplant, and green pepper plants.
 * Usually it is taken in by inhalation of smoke from cigarettes, cigars, and pipe tobacco, but it can also be obtained by chewing.
 * It is lipid (fat) soluble molecule and so is easily able to blood-brain barrier (your brain is mostly made of fat) and thus affects brain activity.
 * Increases the release of adrenaline
 * As with other drugs, its effects change with time, bringing about dependence and increased toleration.
 * <span style="color: rgb(0, 0, 0);">If you are interested in how nicotine effects brain function go to: <span style="color: rgb(255, 0, 0);">__<span style="color: rgb(255, 0, 0);">[] __
 * Short term physiological effects of nicotine:**
 * increased heart rate / blood pressure
 * reduced urine output
 * Increased levels of concentration
 * Long term physiological effects:**
 * <span style="font-family: Verdana,Geneva,sans-serif; font-size: 110%;">Increased risk of cancer
 * <span style="font-family: Verdana,Geneva,sans-serif; font-size: 110%;">Increased risk of heart disease / stroke
 * <span style="font-family: Verdana,Geneva,sans-serif;">Increased risk of emphysema and bronchitis
 * <span style="font-family: Verdana,Geneva,sans-serif;"><span style="font-family: Verdana,Geneva,sans-serif;">Withdrawal symptoms / Weight gain on quitting
 * Other side effects:**
 * development of tolerance
 * risk of becoming dependent

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**<span style="color: rgb(0, 0, 255);">D.5.4 **
<span style="color: rgb(0, 0, 255);">**Describe the effects of caffeine and compare its structure with that of nicotine**. <span style="color: rgb(0, 0, 255);">


 * Effects of Caffeine**
 * Stimulates the nervous system by increasing the metabolic rate of nerve cells.
 * Widely used stimulant, present in coffee, tea, chocolate, and colas.
 * It is legal and unregulated almost everywhere (with nearly 90% of adults consuming it).
 * In general, an intake of more than four cups of coffee per day is excessive. Pregnant women are advised to limit their caffeine intake.


 * Comparison of the structures of nicotine and caffeine

Similarities**
 * <span style="font-family: Verdana,Geneva,sans-serif;">Both contain a tertiary amine group.
 * <span style="font-family: Verdana,Geneva,sans-serif;">Both contain and five member rings made of carbon and nitrogen atoms.
 * <span style="font-family: Verdana,Geneva,sans-serif;">Both contain a six member ring made of carbon and nitrogen


 * Differences**
 * <span style="font-family: Verdana,Geneva,sans-serif;">Caffeine contains two amide groups, nicotine does not.
 * <span style="font-family: Verdana,Geneva,sans-serif;">Both contain an alkene (C=C) group. Caffeine has one and nicotine has two
 * <span style="font-family: Verdana,Geneva,sans-serif;">In caffeine the six and five member rings are fused while in nicotine they separated.
 * <span style="font-family: Verdana,Geneva,sans-serif;">Caffeine contains two carbonyl (C=O)groups and two amide (-N-C=O) groups

<span style="font-family: Verdana,Geneva,sans-serif;">Works Cited Neuss, Geoffrey. __IB Diploma Programme Chemistry Course Companion.__ Oxford: Oxford University Press, 2007. Bro wn, Catra and Mike Ford. __Standard Level Chemistry.__ Heinemann Baccalaureate, 2008. <span style="font-family: Verdana,Geneva,sans-serif;">Derry, Lanna, Maria Connor and Carol Jordan. __Chemistry for use for the IB Diploma Standard level.__ Melbourne: Pearson Education, 2008. IB Chemistry Data Booklet