Drugs and Alcohol
Drugs change body chemistry; some are addictive.
About this topic
Drugs are chemicals that alter how the body works. Medicinal drugs treat disease; recreational drugs affect the nervous system. Stimulants (caffeine, nicotine) speed it up, depressants (alcohol) slow it down, and hallucinogens alter perception. Many are addictive, causing dependence and withdrawal symptoms.
Many drugs act at synapses, changing how neurotransmitters work. With repeated use the body builds tolerance, so more is needed for the same effect. Alcohol is broken down by the liver, and heavy drinking causes liver damage (cirrhosis), brain damage, heart disease and increased accident risk. Alcohol slows reactions, which is why drink-driving is dangerous.
In the short term alcohol reduces inhibitions and impairs judgement, coordination and memory; in the long term it harms the stomach and liver and can cause dependence. During pregnancy it can cause foetal alcohol syndrome, harming the baby's development.
Medicines go through trials to test safety and effectiveness, using placebos and double-blind designs. Painkillers such as aspirin and antibiotics have different actions. A common misconception is that legal drugs are safe; alcohol and tobacco cause huge harm. Another is that addiction is only a lack of willpower, when it involves changes in the brain.
Key ideas
- Medicinal vs recreational
- Depressants slow the brain
- Addiction and withdrawal
Quick check
Use cases: where Drugs and Alcohol helps
- Homework: review the key idea behind Drugs and Alcohol before you start a problem set.
- Exam revision: use the quick check to test whether you can recall Drugs and Alcohol without notes.
- Visual learning: play with the interactive lab to see how Drugs and Alcohol changes when you adjust its inputs.
- Teaching a friend: explain Drugs and Alcohol in your own words, then compare your version with the key ideas.
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Frequently asked questions
What is Drugs and Alcohol?
Drugs change body chemistry; some are addictive.
What will I learn in Drugs and Alcohol?
Medicinal vs recreational. Depressants slow the brain. Addiction and withdrawal.
Is Drugs and Alcohol part of Biology?
Yes. It is one of 150 Biology topics on LearnViz HighSchoolEdu, with 3 key ideas, a live animation and a quick check.
Does the Drugs and Alcohol lab work on a phone or tablet?
Yes. The animation resizes to fit your screen and supports touch, so you can drag, tap and slide with your finger.
How should I study Drugs and Alcohol?
Read the summary and key ideas first, play with the interactive lab to see the idea in motion, then answer the quick check. If you get a question wrong, go back to the key idea it tests.
Do I need an account, and is my progress saved?
No account is needed. Marking a topic as learned is saved in your own browser, so it stays on that device and is not sent to a server.