How Vaccines Train the Immune System: Reading Answers & Explanations
IELTS Reading practice test · 14 questionsAcademicmedium
Haven't taken this test yet?
Looking at the answers first spoils the practice — you only get one honest first attempt at a passage. Take the test with the 20-minute timer, get an instant score and estimated band, then come back here to study every answer.
About this passage
The passage opens: “The human body is constantly exposed to bacteria, viruses and other microorganisms, many of which can cause disease. To defend itself it relies on the immune system, a complex network of cells and molecules that recognises invaders and works to destroy them.”
- Passage length: about 769 words
- Questions: 14
- Question types: True / False / Not Given, Multiple Choice, Short Answer
“How Vaccines Train the Immune System” is an original IELTS-style practice passage written by IELTS-Bank. It is not taken from an official IELTS or Cambridge test, so these answers only apply to our version.
Answer key at a glance
How Vaccines Train the Immune System answers with explanations
Questions 1–6: True / False / Not Given
Do the following statements agree with the information given in the passage? Write TRUE if the statement agrees, FALSE if it contradicts, or NOT GIVEN if there is no information.
- 1
The immune system responds instantly the very first time it meets a harmful microbe.
Show answerHide answer
Answer: FALSE
Why: This sentence directly contradicts the statement, so the answer is FALSE.
Evidence · Paragraph 2 “When a harmful microbe enters the body for the first time, the immune system does not react instantly.”
- 2
A vaccine exposes the immune system to antigens without causing the disease.
Show answerHide answer
Answer: TRUE
Why: This sentence confirms the statement, so the answer is TRUE.
Evidence · Paragraph 3 “A vaccine works by presenting the immune system with these antigens in a form that does not cause the disease.”
- 3
All vaccines provide complete protection after only one dose.
Show answerHide answer
Answer: FALSE
Why: This sentence directly contradicts the statement, so the answer is FALSE.
Evidence · Paragraph 5 “Some vaccines do not produce lasting protection after a single dose. For this reason many are given as a series of injections”
- 4
Herd immunity can protect people who cannot be vaccinated themselves.
Show answerHide answer
Answer: TRUE
Why: This sentence confirms the statement, so the answer is TRUE.
Evidence · Paragraph 6 “This effect, known as herd immunity, indirectly shields those who cannot be vaccinated themselves, such as newborn babies or people whose immune systems are weakened by illness.”
- 5
Smallpox has been completely eliminated through a global vaccination campaign.
Show answerHide answer
Answer: TRUE
Why: This sentence confirms the statement, so the answer is TRUE.
Evidence · Paragraph 7 “…one, smallpox, has been eliminated entirely through a global vaccination campaign.”
- 6
Vaccines are more expensive to produce than most other medicines.
Show answerHide answer
Answer: NOT GIVEN
Why: The statement claims that vaccines are more expensive to produce than most other medicines, but the passage never confirms or denies this, only discussing the methods and challenges of vaccine production.
Question 7: Multiple Choice
Choose the correct letter, A, B, C or D.
- A. Its ability to work without any cells
- B. Its memory of threats it has previously defeated
- C. Its independence from antibodies
- D. Its ability to prevent all infections permanently
- 7
What does the passage say makes the immune system so remarkable?
Show answerHide answer
Answer: B — Its memory of threats it has previously defeated
Why: This is the part of the passage that supports B — Its memory of threats it has previously defeated.
Evidence · Paragraph 1 “One of the most remarkable features of this system is its memory: once it has encountered a particular threat and defeated it, it can respond far more quickly and effectively if the same threat ever returns.”
Question 8: Multiple Choice
Choose the correct letter, A, B, C or D.
- A. Weakened microbes used in vaccines
- B. Proteins that lock onto specific targets on a microbe
- C. The genetic instructions delivered by some vaccines
- D. Cells that live in the blood for a lifetime
- 8
According to the passage, what are antibodies?
Show answerHide answer
Answer: B — Proteins that lock onto specific targets on a microbe
Why: This is the part of the passage that supports B — Proteins that lock onto specific targets on a microbe.
Evidence · Paragraph 2 “…antibodies, proteins that lock onto specific targets on the surface of a microbe.”
Question 9: Multiple Choice
Choose the correct letter, A, B, C or D.
- A. One made from living microbes that have been weakened
- B. One that removes antigens from the body
- C. One that permanently prevents the immune system from forming memory
- D. One that replaces the body's own cells
- 9
Which of the following is described as a type of vaccine?
Show answerHide answer
Answer: A — One made from living microbes that have been weakened
Why: This is the part of the passage that supports A — One made from living microbes that have been weakened.
Evidence · Paragraph 4 “Some contain living microbes that have been weakened, or attenuated, so that they can no longer cause serious illness but still provoke a strong response.”
Question 10: Multiple Choice
Choose the correct letter, A, B, C or D.
- A. Herd immunity becomes stronger
- B. Diseases that had almost disappeared may return
- C. Memory cells last longer
- D. The immune system stops producing antibodies
- 10
What may happen if vaccination rates in a population fall?
Show answerHide answer
Answer: B — Diseases that had almost disappeared may return
Why: This is the part of the passage that supports B — Diseases that had almost disappeared may return.
Evidence · Paragraph 6 “If vaccination rates fall, however, this protective barrier can break down, and diseases that had almost disappeared may return.”
Questions 11–14: Short Answer
Answer the questions below. Choose NO MORE THAN THREE WORDS from the passage for each answer.
- 11
What is the name for the specific molecules that the immune system learns to recognise?(max 2 words)
Show answerHide answer
Answer: antigens (also accepted: antigen)
Why: The answer “antigens” is taken from this sentence — copy the word(s) exactly as they appear. It fits the 2-word limit.
Evidence · Paragraph 2 “The particular molecules that the immune system learns to recognise are known as antigens.”
- 12
What long-lived cells does a vaccine generate so the body can recognise a microbe quickly later?(max 3 words)
Show answerHide answer
Answer: memory cells (also accepted: long-lived memory cells)
Why: The answer “memory cells” is taken from this sentence — copy the word(s) exactly as they appear. It fits the 3-word limit.
Evidence · Paragraph 3 “…by generating long-lived memory cells that remain in the blood and tissues for months, years or even a lifetime.”
- 13
What word describes a living microbe that has been weakened for use in a vaccine?(max 2 words)
Show answerHide answer
Answer: attenuated (also accepted: weakened)
Why: The answer “attenuated” is taken from this sentence — copy the word(s) exactly as they appear. It fits the 2-word limit.
Evidence · Paragraph 4 “Some contain living microbes that have been weakened, or attenuated”
- 14
What is the indirect protection called that occurs when a large proportion of a population is immune?(max 2 words)
Show answerHide answer
Answer: herd immunity (also accepted: herd)
Why: The answer “herd immunity” is taken from this sentence — copy the word(s) exactly as they appear. It fits the 2-word limit.
Evidence · Paragraph 6 “This effect, known as herd immunity, indirectly shields those who cannot be vaccinated themselves”
Estimated band score for this test
Your raw score out of 14 scaled to the 40-question IELTS Reading (Academic) conversion table. This is the same estimate the practice page shows after you submit. A single passage is a small sample, so treat it as a guide.
| Correct answers | Estimated band |
|---|---|
| 14 / 14 | 9.0 |
| 13 / 14 | 8.5 |
| 12 / 14 | 7.5 |
| 11 / 14 | 7.0 |
| 10 / 14 | 6.5 |
| 8–9 / 14 | 6.0 |
| 7 / 14 | 5.5 |
| 6 / 14 | 5.0 |
| 5 / 14 | 4.5 |
| 4 / 14 | 4.0 |
| 3 / 14 | 3.5 |
| 2 / 14 | 3.0 |
| 1 / 14 | 2.0 |
| 0 / 14 | 0.0 |
Full-test score? Use the IELTS band calculator.
Tips for the question types in this test
True / False / Not Given
- Read the statement first and underline the key idea, especially any qualifiers like "all", "only", "never", "always", "more than" or dates and numbers.
- Because the questions follow the order of the passage, scan for the paragraph that deals with the same topic rather than re-reading everything.
Common trap: Confusing "False" with "Not Given": choose False only when the passage actively contradicts the statement; if the passage is silent, it is Not Given.
Full True / False / Not Given strategyMultiple Choice
- Read the question stem carefully before the options so you know exactly what is being asked.
- Because multiple-choice questions follow passage order, locate the relevant section and read it in full — the answer usually depends on more than one sentence.
Common trap: Distractors that use exact words from the passage but distort the meaning.
Full Multiple Choice strategyShort Answer
- Read the instructions and note the exact word limit; going over it means zero marks even if the meaning is right.
- Turn each question into a set of keywords and predict what kind of answer it needs (a person, a date, a place, a noun).
Common trap: Exceeding the word limit (writing four words when only three are allowed).
Full Short Answer strategyPractise “How Vaccines Train the Immune System” under exam conditions
Free, auto-marked, with the 20-minute timer and an instant band estimate.
Take this test first (timed)More IELTS Reading tests with answers
Why the Sky Is Blue
medium
Working at Fairfield Foods: Conduct and Overtime
medium
A Beginner's Guide to Home Composting
easy
A Brief History of Money
medium
A History of the World in Board Games
medium
A Short History of Tea
medium