Cambridge Past Paper Questions
Browse 23,045questions from 25 years of O-Level & A-Level exams. Click any question to practice.
4 A 28-year study of Magellanic penguins, Spheniscus magellanicus, found in Argentina, provides evidence of natural selection. Magellanic penguins ...
5 Mimulus is a plant genus containing a diverse range of species that have colourful flowers to attract pollinators, such as bees and hummingbirds....
6 Mining may result in the release of heavy metal ions, causing pollution of lakes and rivers. High concentrations of these heavy metal ions, such ...
7 (a) Gibberellin is involved in the germination of barley seeds. In an investigation, aleurone layers from barley seeds were extracted. One sample...
8 The passage below outlines the structure of the mitochondrion. Complete the passage by using the most appropriate scientific term(s). The mitocho...
9 (a) Viruses are not included in the three domain classification system as they have different features from most organisms. Describe the features...
10 (a) Describe the roles of the neuromuscular junction, transverse system tubules (T-tubules) and the sarcoplasmic reticulum in stimulating contra...
Chlorella is a photosynthetic, single-celled protoctist that lives in ponds. A group of students decided to investigate the effect of temperature o...
A fungal pathogen infects melon plants and causes the leaf cells to lose turgor. The melon plant then becomes permanently wilted.
A group of students investigated the growth of different varieties of yeast. The students learned that the rate of respiration in a yeast culture i...
Populations of European ash trees, Fraxinus excelsior, are susceptible to a chronic tree disease called ash dieback. Since 2012, this disease has s...
The size of the measles virus, Morbillivirus, is approximately 150 nm. The Mimivirus is approximately 4.5 times larger than Morbillivirus, whilst t...
The electron micrograph shows a type of virus at a magnification of ×60000. [Figure 2.1] What is the actual length of the virus?
The electron micrograph shows a structure found in the cytoplasm of an animal cell. [Figure 3.1] Which biological molecules are found in this struc...
Which are found in typical prokaryotic cells and in typical plant cells? 1 cell wall 2 circular DNA 3 cytoplasm
The diagram shows some features that occur in organisms. [Figure 6.1] Which features can be present in viruses?
Diastase is an enzyme that breaks down starch into maltose. Maltose is a reducing sugar. A sample of starch is treated with boiled diastase and lef...
Which pair of monosaccharides forms sucrose? [Figure 8.1]
The diagram shows the structures of two amino acids. [Figure 9.1] These amino acids will form part of a protein that has a tertiary structure. Whic...
Which row about the structure of proteins is correct? [Figure 10.1]
Which row correctly identifies structural features of a collagen molecule and a haemoglobin molecule? [Figure 11.1]
Which statements describe some enzyme actions? 1 Enzymes hold reacting molecules so that their reactive groups are close together. 2 In an enzyme-c...
Lipase is an enzyme that catalyses the hydrolysis of lipids. An experiment was carried out to investigate changes in pH when lipase is added to a f...
The painkiller ibuprofen reduces the activity of an enzyme involved in the production of prostaglandin. Ibuprofen binds reversibly to the active si...
Equal-sized potato pieces were placed into test-tubes containing equal volumes of different concentrations of sucrose solution and left for 30 minu...
Four agar blocks are stained green using universal indicator and suspended in 1 moldm⁻³ hydrochloric acid. [Figure 16.1] The time taken for the aga...
During the cell cycle, the mass of DNA in a cell is doubled. At which stage in the cell cycle is the mass of DNA in a cell reduced?
In eukaryotes, the chromosomes become shorter and thicker during mitosis. The thickening may be increased by molecules called protamines. The prota...
How many hydrogen bonds are holding the two strands of this section of a DNA molecule together? [Figure 20.1]
Which description of a eukaryotic gene is correct?
The DNA sequence CCAAGAAGTCGACAAACA is translated to synthesise the amino acid chain gly-ser-ser-ala-val-cys. As a result of a mutation, the sequen...
Which combination of features is correct for a phloem sieve tube element as it unloads into a sink? [Figure 23.1]
Mass flow is the bulk movement of materials from one place to another. Which vessels carry fluids by mass flow? 1 artery 2 phloem sieve tube 3 vein...
Which two rows are correct for the movement of water from the soil into a root? [Figure 25.1]
ATP is used in companion cells to provide the energy for loading a sieve tube element with sucrose. How does the co-transporter mechanism use this ...
Why is the mammalian circulatory system described as a double circulation?
Which sequence of letters correctly identifies the order of events during the cardiac cycle? T atrial walls contract U impulse is delayed a fractio...
Which factors affect blood pressure? 1 the diameter of the blood vessels 2 the systolic pressure of the heart ventricles 3 the volume of blood retu...
The diagram is a summary of the role of haemoglobin in the transport of carbon dioxide. [Figure 30.1] Which set of labels is correct?
The graph shows the oxygen dissociation curves of haemoglobin from two species of mammal, S and T. [Figure 31.1] Which statements could explain the...
Which are present in bronchioles? 1 endothelium 2 ciliated cells 3 smooth muscle tissue
The partial pressure of oxygen in air inside alveoli is 14 kPa. The partial pressure of oxygen in pulmonary capillaries is 6 kPa. What will be the ...
Which can be directly linked to a reduction in the surface area available for gas exchange in human lungs? 1 emphysema 2 lung cancer 3 smoking tobacco
Which row is correct about the affinity between haemoglobin and the gases carbon dioxide, carbon monoxide and oxygen? [Figure 35.1]
An earthquake caused damage to sanitation systems in a large tropical village. Drinking water became contaminated with sewage. Heavy rain then caus...
Which statements about the use of antibiotics could cause an increase in antibiotic-resistant bacteria? 1 Patients do not always complete the cours...
Which row is correct for neutrophils and B-lymphocytes? [Figure 38.1]
Rabies is usually a fatal disease. Rabies is transmitted to people in the saliva of infected animals. A person who has been bitten by an infected a...
Fig. 1.1 is a diagram of a human chromosome at a stage in mitosis. [Figure 1.1]
Fig. 2.1 shows the molecular structure of a triglyceride molecule. [Figure 2.1]