Download Option D IB Chemistry Definitions SL

Chemistry: Definitions
Option D – Medicine and Drugs – SL
Addiction:
Problem with opiates, in which a dependency on a drug is created.
Adrenaline:
A naturally occurring hormone and stimulant. Released during stress. Responses:
1) Increased pulse;
2) dilation of pupils;
3) sweating;
4) diversion of blood to muscles;
5) decreased blood clotting time. Fat insoluble. Both amphetamine and
adrenaline are based on the framework of a benzene ring with a two carbon chain and
an amine (NH2 or NH) group at the end.
AIDS:
Acquired Immune Deficiency Syndrome. Develops from HIV.
Alginates:
Often combined with antacids. Prevent acid in stomach from rising into esophagus and
causing ‘heartburn.’
Amine:
Primary amines have one R group attached to N atom. Secondary have two on at least
one N atom. Tertiary have three on at least one N atom.
Amphetamine:
Fat soluble molecule which mimics noradrenaline. Similarity is so strong that it can
replace noradrenaline in its storage sites, resulting in a flood of displaced
noradrenaline molecules that bind to other neural proteins and set of a number of
signals  euphoria.
Analgesic, mild:
Have triad of properties:
1) analgesic (pain relief);
2)antipyretic (fever reduction);
3) anti-inflammatory (reduces swelling). Believed that they work by blocking
synthesis of prostaglandins.
Analgesic, strong:
Analgesics that bind with specific chemical receptors in brain that receive pain
messages  stopping the transmission of pain. They are almost all related to
morphine. Family is called the opium alkaloids.
Analgesic:
A drug which relieves pain without the aid of sleep. Two types:
1) mild;
2)strong.
Antacids:
Bases that neutralize excess acid. They are just barely soluble  neutralize gradually.
Antibiotics, broad spectrum: Antibiotics that are effective against a wide range of bacteria. This is initially
prescribed until the specific diagnosis is found.
Antibiotics, narrow spectrum:
Antibiotics only effective against certain types of bacteria. Prescribed once
the specific diagnosis is found.
Anti-coagulant:
Has blood-thinning properties.
Antivirals:
Three possible approaches:
1) Trojan Horse (joins the replication process, inhibiting replication of the
virus. Selectively toxic as it is activated by viral enzyme);
2) Retrovirus inhibitor (inhibits RNA from acting as a template for DNA
replication);
3) blunting (preventing escape of new viruses by inhibiting neuraminidase
enzyme which cuts open cell membrane).
Aspirin:
Derived from salicylic acid, which was unpleasant to use due to its acidity. The phenol
group is substituted with an acetyl group in aspirin, but it is still acidic due to its
alkanoic acid group. Has anti-coagulant properties, but there can be allergic
reactions to it and it can induce Reye’s Syndrome in children, a potentially fatal liver
and brain disorder.
Bacteria:
Have slightly different structure to mammalian cells: have a cell wall. Penicillin prevents
this wall from being made, and the internal pressures within the cell builds up and
causes it to burst.
Benzodiazepenes:
Class of depressants, including valium, prozac and mogadon. Benzodiazepenes work on
chemical receptors in brain by binding to a special protein at the synapse of nerve
junctions, causing gap between nerves to widen  prevents nerve cell from producing
signal. The ethanol works on a different part of the same protein. The synergistic
effect of these two working together can result in neural shutdown.
Blood-brain barrier:
Can only by passed by fat soluble molecules.
Caffeine:
A tertiary amine. Can
1) promote mild dependence;
2) act as a mild diuretic;
3) increase anxiety (when taken in excess);
4) cause insomnia. Known as respiratory stimulant, as it increases rate of
respiration, by blocking inhibition of ATP. It does so by mimicking the shape of the
ATP and causes the inhibiting enzyme to bind to it instead.
Cephalosporins:
Variants of penicillin created to overcome the action of penicillinases. Broad spectrum
antibiotics.
CNS:
Central Nervous System.
Codeine:
Derived from morphine by replacing H in one of alcohol groups with methyl group.
Depressant:
Drugs which depress CNS by interfering with transmission of nerve impulses in the
neurons. Effects depend on dosage: no effect  tranquilizing effect  sedative 
sleep-inducing  lethal.
Designer drugs:
Modifications to structure of natural drugs.
Dimethicone:
An anti-foaming agent often used with antacids. Allow gas bubbles to coalesce and be
expelled.
Drug administration:
Five methods:
1) Oral (subjected to digestive process; easiest);
2)Rectal (efficient, cultural biases);
3) inhalation (drug can only be absorbed through lungs);
4) Parenteral (see PARENTERAL);
5) Patches (absorbed directly through skin barrier, allow absorption to take
place gradually).
Drug development:
A disease is selected, and targets along the disease process are identified, which may
be vulnerable to interference by a drug. Lead molecules are considered, and selected
according to the drugs which seem most effective, easiest to manufacture, have an
advantage over existing drugs and are profitable. Phase I trials assess toxicology of
drug. Phase II trials are clinical; the efficacy and dosage are determined. Phase III
trials give the drug to thousands of closely monitored patients. If approved at this
stage, drug is launched, after which comes the Phase IV trials, which is the postlaunch monitoring of drug, which may lead to product extension.
Drug:
A chemical which does one or more of the following:
1) alter mood or emotions;
2) alter incoming sensory sensations;
3) alter physiological state.
Endorphins:
Pain killers produced in the brain. Explain how people under great trauma feel little pain
despite terrible injuries. Withdrawal symptoms of a heroin addict might be behavior
of body without any endorphins at all.
Ethanol:
Mild depressant in which side effect mask the main effect in moderate doses.
Physiological effects:
1) decreasing inhibitions;
2) short term reduction in reaction speed;
3) short term hangover;
4) long term liver damage.
Social and economic effects:
1) violent behavior;
2) increase in car accidents;
3) absenteeism;
4) cost of intensive medical care.
The amount of alcohol that can be safely drunk depends on
1) body mass;
2) tolerance.
Gas chromatography:
Test for ethanol. Under pressure, sample can be passed through thin tube containing
inert material. Components of sample separate and can be identified.
Heroin:
Derived from morphine by replacing H’s from both alcohol groups with acetyl (-COCH3)
groups. More soluble in fatty tissue due to removal of both -OH groups.
HIV:
Human Immunodeficiency Virus. Specific proteins on HIV bind to receptor protein on
certain WBC’s called T cells. Quick mutation.
In vitro:
Testing potency of molecule and selectivity; done in a laboratory environment.
In vivo:
Meaning “in life.” Tests conducted in living species, to test for side effects and the
effect of the body on the drug.
Intoximeter:
Test for ethanol. Work by infrared spectroscopy, where the vibration of OH bond in
ethanol can be detected.
LD50 value:
The Lethal Dose of a substance that kills of 50% of a population. The lower the number
the more toxic the substance.
Maximum daily tolerance: How much of a chemical can be taken into the body before undesirable symptoms occur.
Related to rate at which body’s biochemistry is able to get rid of the same agent.
Minimum doses should be used due to body’s increasing tolerance to drug.
Medicine:
A drug used to cure a disease.
Nicotine:
Sympathomimetic. Quickly reaches CNS.
Short term effects:
1) Increased pulse and BP;
2) reduction in urine output;
3) decrease in reflex times,
4) increases concentration;
5) relieves tension.
Long term effects:
1) Risk of heart disease;
2) coronary thrombosis;
3) peptic ulcers;
4) number of diseases, incl. lung cancer.
Nicotine is a tertiary amine.
Noradrenaline:
Variation of adrenaline which is produced in the brain. A neurotransmitter which sends
signals to brain by binding with neural proteins.
Opiate:
Cause addiction and lead to tolerance.
Short-term effects:
1) euphoria;
2) depression of CNS;
3) high doses  coma/death.
Long-term effects:
1) constipation;
2) loss of sex drive;
3) social problems (e.g. theft, prostitution, etc).
Paracetamol:
Has none of the side effects of aspirin given that the correct does is used. If doses
are exceeded, it can induce massive liver damage.
Parenteral:
Administering drugs by injection. Can be administered locally  reducing dose
necessary and also possibility that body will alter molecular structure. Often
required medically trained staff to administer. Three types:
1)intravenous (bypasses digestive system, quick arrival; still spreads out
dose);
2) subcutaneous (directly into body fat – only for fat soluble molecules);
3)intramuscular (into muscle tissue).
Pathogen:
Organism or virus that causes disease.
Penicillin:
Discovered by Alexander Fleming, who noticed that some of the bacteria in his petri
dish had died off after some foreign appearance. Prevent cell walls from being made
in bacteria; does not affect mammalian cells or viruses as they do not have a cell wall
 selectively toxic. [Relatively] narrow spectrum antibiotic.
Penicillinases:
New enzymes produced by bacteria to counter the action of penicillin. Degrade
penicillin molecule.
Physiological state:
Includes consciousness, activity level and co-ordination.
Placebo effect:
A drug with no chemical effects. Used to test brain’s ability to influence physiology and
to test the efficacy of new drugs.
Prostaglandins:
Local action hormones which have a range of functions in body. One of these may be
pyrogenic (raise body temperature). Also responsible for altering of signals across
synapse junctions of nerves. Mild analgesics are believed to work by blocking the
synthesis of these prostaglandins.
Retrovirus:
Virus that contains RNA instead of DNA.
Selective toxicity:
The process of inhibiting processes vital to the pathogen, but absent in the host (see
PENICILLIN).
Side effects:
Unwanted effects of a drug. Risk-to-benefit ratio has to be considered. Thalidomide
had an unacceptable ratio, while chemotherapy – causing hair loss and nausea – still
has life-saving potential.
Stimulant:
Drugs that increase a person’s state of mental alertness.
Sympathomimetic amine:
Amines which mimic chemical behavior of hormones of the CNS.
Synergistic effect:
Creating a cumulative effect greater than the sum of each individual effect.
Benzodiazepenes have synergistic effect with ethanol. Ethanol also has synergistic
effect with aspirin (may cause stomach bleeding).
Thalidomide:
Morning sickness drug sold world-wide despite severe side-effects. Early clinical trials
had shown problems, but due to profitability, drug was not withdrawn. Later
withdrawn, but many children had been born with absent or malformed limbs.
Tolerance:
The body’s adaptation to the action of a drug, resulting in a requirement for larger
doses to achieve original effect.
Toxicology:
Poisonous effect of drug.
Trial, blind:
A trial of drugs where half of the patients are given the real drug and the other half a
placebo. The administering doctors know which patient receives which drug.
Trial, double blind:
Similar to blind trial except that neither the administering doctor nor the patient
knows which patient receives which drug.
Virus:
Contains DNA but cannot replicate by itself. Works by sticking to the outside of a cell,
and inject its own DNA, effectively causing cell to replicate the virus for it. New
viruses break through cell and infect other cells. All viruses have a central core of
DNA or RNA surrounded by a capsid of regularly packed protein units (capsomeres).
Have no nucleus or cytoplasm.