In an exam, answer drug questions with general biology: what the substance acts on and what follows. Do not tell a person what to take, how much, or when. That is a decision for a doctor or pharmacist who knows the real situation.
This lesson finishes drugs and biological effects. It works alongside distinguishing a medicine from a mechanism and the care with conclusions from correlation limits in data.
Why does wording matter in biology answers?
Two kinds of sentence can look similar.
A general statement describes how something works for anyone. Example: “Antibiotics act on bacterial cells, not on viruses.”
A personal instruction tells someone what to do. Example: “You should take an antibiotic for your cold.”
The general statement is correct, testable and what the mark scheme rewards. The personal instruction is not something a biology exam, a textbook or a tuition lesson can responsibly give.
A reliable way to check your sentence
Ask three questions before you finish an answer.
- Does the sentence describe what a type of substance does, rather than what a person should do?
- Does it use third-person, general wording such as “the drug”, “the bacteria”, “a person who is ill”?
- Is every claim something you can link to a biological reason?
If the answer to any is no, rewrite it.
Worked example
Question (invented scenario): A student has a cold caused by a virus and asks whether taking an antibiotic would help. Use biology to respond.
Step 1, identify the cause: a cold is caused by a virus.
Step 2, recall the mechanism: antibiotics act on features of bacterial cells. Viruses are not bacterial cells and do not have those features.
Step 3, link them: the antibiotic has nothing to act on, so it would not treat a viral illness.
Step 4, keep it general. Write “antibiotics are not effective against viral infections” rather than “you should not take one”.
Model answer: a cold is caused by a virus. Antibiotics act on bacterial cells, and viruses are not bacterial cells, so an antibiotic would not be effective against the cold.
If the question itself asks what the student should do, you may add one short sentence: “For a real health situation, a doctor or pharmacist gives advice.” The marks still come from the science in the lines above.
The mistake to watch for
Mistaken answer: “Yes, take the antibiotic for three days and you will feel better.”
This gives a personal instruction and a dose-style detail, neither of which the question asks for. It is also scientifically wrong for a viral illness, because the drug would have no bacterial target.
The correction is the model answer above: general wording, a biological reason and no instruction to the person.
Check yourself
1. Which sentence is suitable for an exam answer? (a) “You should stop taking your medicine when you feel well.” (b) “Some drugs reduce activity at synapses, so responses become slower.”
Show answer
(b). It is a general biological statement. Sentence (a) is a personal instruction about a real medicine, which a biology answer should not give.
2. Rewrite in general wording: “You should avoid alcohol because it will slow your reactions.”
Show answer
“Alcohol is a depressant that slows activity in the nervous system, so reaction times increase.” This states the biology and does not instruct anyone.
3. A question asks why antibiotics do not cure a viral illness. Write one sentence of model answer.
Show answer
“Antibiotics act on bacterial cells, but viruses are not bacterial cells, so the antibiotic has no target in a viral infection.”
Where this leads next
Put all five skills together in the drugs and biological effects practice set. Keep a record of any wording slips in the mistake log and retest queue.
This page is a study guide and does not give health advice. If wording slips keep costing you marks, our teachers can work on them with your own answers in online one-to-one Biology tuition.