June 2026 exams are close. If your child is sitting IGCSE Biology Paper 2, these are the MCQs they need to revise right now.
Why MCQ Revision Matters More Than Most Students Think
Most IGCSE Biology students spend the majority of their revision time on long answer questions. They practise written responses, work on diagrams, and memorise definitions.
And then they sit Paper 2 and lose marks on MCQs they thought would be easy.
This happens more often than parents and students expect. MCQs in IGCSE Biology Paper 2 are not simple recall questions. They are carefully written to test understanding. The wrong answer options are designed to catch students who have half understood a concept. One small gap in knowledge and the mark is gone.
The good news is that MCQ revision for IGCSE Biology is very targeted. The same topic areas come up again and again. If your child revises the right areas carefully before June 2026, they can walk into Paper 2 feeling genuinely prepared.
Here are the top 20 MCQ topics and questions your child must go through before exam day.
Cell Biology and Transport
Question 1 Which process moves glucose molecules from a region of high concentration to low concentration without using energy?
A. Active transport B. Osmosis C. Diffusion D. Facilitated diffusion
Answer: C
Why students get this wrong: Many students confuse diffusion with facilitated diffusion. Both move substances down a concentration gradient without energy. The difference is that facilitated diffusion uses protein channels. Plain diffusion does not. Glucose moving across a simple concentration gradient without any mention of protein channels means the answer is diffusion.
Question 2 A red blood cell is placed in a solution with a lower water potential than the cell. What happens?
A. The cell swells and bursts B. The cell shrinks C. The cell stays the same D. The cell takes in water by active transport
Answer: B
Why students get this wrong: Students mix up which direction water moves. Water always moves from higher water potential to lower water potential by osmosis. If the outside solution has lower water potential, water moves out of the cell. The cell shrinks.
Question 3 Which structure controls what enters and leaves the cell?
A. Cell wall B. Nucleus C. Cell membrane D. Vacuole
Answer: C
Why students get this wrong: Some students write cell wall out of habit. The cell wall provides structure but does not control what passes through. The cell membrane is selectively permeable and controls entry and exit.
Enzymes
Question 4 An enzyme is placed in a solution at pH 2. Its activity is very low. The pH is changed to 7 and activity increases. What explains this?
A. More substrate molecules are present B. The enzyme is now at its optimum pH C. Temperature has increased D. The enzyme concentration has increased
Answer: B
Why students get this wrong: Students sometimes choose A because they associate more activity with more substrate. But the question is specifically about pH change. At pH 7 the enzyme is closer to its optimum, so the active site shape is better suited to the substrate.
Question 5 What happens to an enzyme at very high temperatures?
A. It becomes more active B. It is digested C. It is denatured D. It dissolves
Answer: C
Why students get this wrong: Students sometimes say the enzyme is killed. Enzymes are not living things. The correct term is denatured. The shape of the active site changes permanently and the enzyme can no longer bind to its substrate.
Question 6 Which statement correctly describes enzyme specificity?
A. Enzymes work on all substrates B. Each enzyme works best at pH 7 C. The active site fits only one specific substrate D. Enzymes are used up in reactions
Photosynthesis and Respiration
Question 7 Which raw materials are needed for photosynthesis?
A. Oxygen and glucose B. Carbon dioxide and water C. Carbon dioxide and oxygen D. Glucose and water
Answer: B
Why students get this wrong: Students mix up the inputs and outputs. Carbon dioxide and water go in. Oxygen and glucose come out. This question comes up in almost every past paper in some form.
Question 8 A plant is kept in darkness for 48 hours. What happens to the rate of photosynthesis?
A. It increases B. It stays the same C. It stops completely D. It slows but continues
Answer: C
Why students get this wrong: Some students think photosynthesis continues at a slower rate without light. It does not. Light is essential for the light dependent reactions. Without light, photosynthesis stops.
Question 9 Which process releases energy from glucose in the absence of oxygen?
A. Aerobic respiration B. Photosynthesis C. Anaerobic respiration D. Transpiration
Answer: C
Why students get this wrong: Students sometimes write aerobic respiration by mistake because they associate respiration with energy release. The key word in this question is absence of oxygen. That points directly to anaerobic respiration.
Genetics and Inheritance
Question 10 A tall plant (TT) is crossed with a short plant (tt). What is the expected phenotype of all offspring?
A. All short B. All tall C. Half tall, half short D. Three tall, one short
Answer: B
Why students get this wrong: Students sometimes expect a mix of phenotypes. When one parent is homozygous dominant and the other is homozygous recessive, all offspring are heterozygous (Tt) and show the dominant phenotype.
Question 11 Which term describes an organism that has two different alleles for a trait?
A. Homozygous B. Dominant C. Heterozygous D. Recessive
Answer: C
Why students get this wrong: Students mix up homozygous and heterozygous. Homozygous means two identical alleles. Heterozygous means two different alleles.
Question 12 A gene has two alleles. One allele codes for brown eyes and is dominant. One allele codes for blue eyes and is recessive. Two heterozygous parents have children. What is the probability of a child having blue eyes?
A. 0 percent B. 25 percent C. 50 percent D. 75 percent
Answer: B
Why students get this wrong: Students who do not draw the Punnett square often guess 50 percent. Drawing out the cross (Bb x Bb) gives BB, Bb, Bb, bb. Only bb shows blue eyes. That is 1 out of 4, which is 25 percent.
Human Biology
Question 13 Which blood vessel carries oxygenated blood away from the heart to the body?
A. Pulmonary vein B. Vena cava C. Aorta D. Pulmonary artery
Answer: C
Why students get this wrong: Students confuse the pulmonary vessels with the systemic vessels. The pulmonary artery carries deoxygenated blood to the lungs. The aorta carries oxygenated blood from the left ventricle to the rest of the body.
Question 14 What is the role of insulin in the body?
A. It increases blood glucose levels B. It converts glucose to glycogen when blood glucose is too high C. It breaks down glycogen when blood glucose is too low D. It is produced by the pituitary gland
Answer: B
Why students get this wrong: Students mix up insulin and glucagon. Insulin lowers blood glucose by converting it to glycogen. Glucagon raises blood glucose by breaking down glycogen. Both are produced in the pancreas, not the pituitary gland.
Question 15 Which part of the nervous system carries impulses from the sense organs to the central nervous system?
A. Motor neurone B. Effector C. Sensory neurone D. Relay neurone
Answer: C
Why students get this wrong: Students mix up motor and sensory neurones. Sensory neurones carry impulses towards the CNS. Motor neurones carry impulses away from the CNS to effectors like muscles and glands.
Ecology and Environment
Question 16 Which term describes all the organisms of the same species living in the same area at the same time?
A. Community B. Ecosystem C. Population D. Habitat
Answer: C
Why students get this wrong: Students confuse population with community. A population is one species. A community is all the species living in the same area. This definition question appears regularly in Paper 2.
Question 17 A food chain shows: grass, rabbit, fox. If the number of rabbits decreases sharply, what is the most likely short term effect on foxes?
A. Fox numbers increase B. Fox numbers decrease C. Fox numbers stay the same D. Foxes start eating grass
Answer: B
Why students get this wrong: Students sometimes think predators find other food immediately. In the short term, less prey means less food for the predator, so predator numbers fall. This is a standard food web question.
Plant Biology
Question 18 Which plant tissue is responsible for transporting water from roots to leaves?
A. Phloem B. Xylem C. Epidermis D. Mesophyll
Answer: B
Why students get this wrong: Students mix up xylem and phloem. Xylem transports water and minerals upwards. Phloem transports dissolved sugars in both directions. A simple way to remember: xylem for water, phloem for food.
Question 19 What causes the stomata to open during the day?
A. Guard cells lose water and become flaccid B. Guard cells gain water and become turgid C. Carbon dioxide concentration increases D. Temperature decreases
Answer: B
Why students get this wrong: Students sometimes get the direction of water movement wrong. During the day, guard cells take in water by osmosis, become turgid, and the stomata open to allow gas exchange and photosynthesis
Disease and Immunity
Question 20 Which type of immunity is provided by vaccination?
A. Natural passive immunity B. Artificial passive immunity C. Natural active immunity D. Artificial active immunity
Answer: D
Why students get this wrong: Vaccination is artificial because it is introduced deliberately, not through natural infection. It is active because the body produces its own antibodies in response to the vaccine antigen. Students often confuse active and passive. Passive immunity involves receiving ready made antibodies, not making your own.
How to Use These MCQs for IGCSE Biology Exam Preparation
Going through this list once is useful. But to really prepare for June 2026, here is how to use these questions properly.
Do not just read the answer. Try each question first without looking. Then check. If you got it wrong, read the explanation carefully and find that topic in your notes or textbook. Do not move on until you understand why the correct answer is correct and why the others are wrong.
Time yourself. In the actual Paper 2 exam, students often spend too long on MCQs and run out of time for the structured questions. Practice answering MCQs quickly and confidently so you do not lose time on exam day.
Go back to past papers. These 20 questions cover the most commonly tested areas but past papers have many more. Cambridge past papers from the last five years are the best resource for IGCSE biology MCQ revision
Still Losing Marks on MCQs?
If your child has gone through these questions and is still getting several wrong, the issue is usually one of two things.
Either there are concept gaps that need to be addressed properly, or your child understands the biology but is not reading the questions carefully enough. Both of these are fixable with the right guidance.
At BioKatalyst, Karishma and Khushbu personally work through past paper MCQs with students in one-on-one sessions. We identify exactly which topics are causing problems and fix them before exam day. No batch system, no assistants, no middlemen. Just direct, personal teaching from teachers with over 13 years of Cambridge biology experience.
FAQs
How many MCQs are in IGCSE Biology Paper 2? IGCSE Biology Paper 2 contains 40 MCQs. Students have 45 minutes to complete the paper. Each question carries one mark so speed and accuracy both matter.
Which topics come up most in IGCSE Biology Paper 2 MCQs? Cell biology, enzymes, genetics, human physiology, photosynthesis, and ecology come up most frequently. These topics are heavily tested across past papers and are the highest priority for MCQ revision.
How should my child prepare for IGCSE Biology Paper 2 before June 2026? Start with topic based revision, then move to full past papers under timed conditions. Go through mark schemes carefully and focus on the questions that were answered incorrectly. Personal guidance helps students identify patterns in their mistakes much faster.
Are these MCQs from real past papers? These MCQs are written in the style of Cambridge IGCSE Biology Paper 2 questions and cover the most commonly tested topics. For real past paper practice, Cambridge past papers are available through the Cambridge website and your school.
My child keeps getting MCQs wrong even after revising. What should we do? This usually means the concept has not been fully understood, just memorised. One-on-one tutoring helps because the teacher can identify exactly where the thinking is going wrong and correct it at that level.
Do you help with full IGCSE Biology exam preparation including Paper 2? Yes. At BioKatalyst we cover all papers including Paper 2 MCQ preparation, structured questions, and exam technique. Karishma and Khushbu personally teach every session.
Book a Free Demo Class With Us Today
June 2026 exams are closer than they feel right now. If your child needs focused personal support to prepare for IGCSE Biology Paper 2, one demo class will show you exactly how we work.
We are online biology tutors with over 13 years of experience in Cambridge biology. We teach IGCSE, AS Level, A Level, and IB Biology directly, personally, and with no middlemen.
Book a free demo class with us today
