Cambridge Past Paper Questions
Browse 23,045questions from 25 years of O-Level & A-Level exams. Click any question to practice.
Control of heartbeat is myogenic. This means the electrical activity controlling the rhythm of a regular heartbeat begins in the heart muscle itsel...
Fig. 6.1 is a diagram showing the structure of part of a DNA molecule. [Figure 6.1] (b) Fig. 6.2 shows the RNA base sequence of a short length of p...
You will investigate the water potential of potato cells. When pieces of potato are put into a sucrose solution, water will move by osmosis into an...
J1 is a slide of a stained transverse section through a plant stem.
The European hedgehog, Erinaceus europaeus, is a small omnivorous mammal. Its body is covered in spines, which are usually brown. A rare variant, w...
Giant axonal neuropathy (GAN) is a rare autosomal recessive disease, which affects neurones. (a) Mitochondria can move freely within the axons of n...
The red blood cells of people with sickle cell anaemia have reduced oxygen-carrying capacity.
(a) Meiosis is an important process that contributes to genetic variation in a population. Fig. 4.1 shows a pair of homologous chromosomes during p...
Factor VIII can be made as a recombinant human protein.
(a) The banana plant, Musa acuminata, is a tall herbaceous plant with very large leaves. Fig. 6.1 shows a banana plant. [Figure 6.1] An investigati...
(a) In aerobic respiration, ATP is synthesised by substrate-linked reactions and by oxidative phosphorylation. Outline the process of oxidative pho...
Natural selection and artificial selection (selective breeding) both have important roles in evolutionary change. (a) Seahorses are fish with an un...
10 (a) Fig. 10.1 shows the structure of two guard cells. [Figure 10.1]
Some students wanted to investigate the effect of light intensity on the rate of photosynthesis in the Brazilian waterweed, Egeria densa. This plan...
An invasive alien species is a species that has been introduced into an ecosystem where it is not normally found and causes harm to this ecosystem....
Mussels, Mytilus edulis, are molluscs that live in sea water on the shorelines of coastal regions around the world. Mussels are a popular seafood a...
The photomicrograph shows cells from a human blood smear. [Figure 1.1] Which calculation shows a correct method to calculate the actual diameter of...
A student calibrated an eyepiece graticule using a stage micrometer. • Each division of the stage micrometer was 0.01 mm. • With a ×10 magnificatio...
Which statements are correct for chloroplasts and also for mitochondria? 1 They contain 80S ribosomes. 2 They can transcribe their circular DNA. 3 ...
The electron micrograph shows some cells from a root. Which cell structure is not usually found in cells from a root?
Dialysis (Visking) tubing is an artificial partially permeable membrane with pore sizes of approximately 2.5 nm. Glucose molecules have a diameter ...
What is present in all viruses?
To estimate the concentration of glucose in an unknown solution, equal volumes of a range of known concentrations of glucose were each mixed with t...
Which statements are correct for amylose and also for amylopectin? 1 They are carbohydrate molecules. 2 They are formed by condensation reactions. ...
Which statement is a correct comparison between saturated triglyceride molecules and unsaturated triglyceride molecules of approximately the same m...
The diagram represents a molecule from a cell surface membrane. [Figure 10.1] Which description of one of the labels is correct?
Which row correctly shows levels of protein structure that can be held together by each type of interaction?
Which molecules contain at least three double bonds? [Figure 12.1]
Which diagram correctly shows hydrogen bonding between two water molecules? [Figure 13.1]
Which statement describes an example of an extracellular enzyme?
Which row is correct for enzymes that catalyse reactions using the lock-and-key hypothesis?
A scientist investigated the rate of breakdown of hydrogen peroxide. Four experiments were carried out using different mixtures. • substrate only •...
What happens to the surface area to volume ratio of a cube when the length of each side is doubled?
Which events are part of the mitotic cell cycle? 1 interphase 2 telophase 3 cytokinesis
The estimated total number of red blood cells in the human body is 2.5 × 10¹³. It is estimated that, each day, 2.5 × 10¹¹ red blood cells are remov...
DNA polymerase catalyses condensation reactions between molecules during semi-conservative replication of DNA. What is joined by DNA polymerase?
Two polynucleotide strands make up a DNA molecule. Which description is correct?
The PDx1 protein is found in a wide range of animal species where it is regarded as essential for normal metabolism. In sand rats, the gene coding ...
Different tissues in a plant were supplied with a radioactively labelled substance to identify which tissues were actively synthesising mRNA. Which...
Which row correctly matches the structure and function of phloem sieve tube elements?
Which feature of xylem vessel elements helps adhesion during transpiration?
Mass flow is the bulk movement of materials from one place to another. How many of the vessels listed carry fluids by mass flow? • artery • phloem ...
Cellulose, lignin and suberin are components of various plant cell walls. Descriptions of these cell wall components are listed. 1 a component of t...
The arrows show the direction of water movement across a plant root, from water in the soil to the xylem. [Figure 29.1] Which arrows show water mov...
Which row correctly identifies sources and sinks of sugars?
The photomicrograph shows a section through a tissue with an artery. [Figure 31.1] Which row correctly shows the type of artery and whether the blo...
Heart surgery may cause a decrease in the transmission of impulses in the Purkyne tissue to the right side of the heart. What is a possible effect ...
The diagram shows a network of blood vessels that supply blood to muscle tissue in the human body. [Figure 33.1] What is a correct comparison betwe...
Scientists have shown that the oxygen dissociation curves for haemoglobin of smaller mammals are to the right of those of larger mammals. What does...