Cambridge & Pearson Edexcel Past Paper Questions
Browse 35,704 questions from Cambridge O-Level & A-Level and Pearson Edexcel IGCSE & IAL exams. Click any question to practice.
How many of the listed structures typically contain genetic material that has telomeres? • bacterial cell • chloroplast • mitochondrion • nucleus
What does the enzyme DNA polymerase synthesise in a cell?
21.2% of the bases in a molecule of DNA are cytosine. What percentage would be adenine?
One gene provides the code for the production of which type of molecule?
The table shows the mode of action of two antibacterial drugs that can affect the synthesis of proteins. If bacteria are treated with both drugs, w...
The diagrams show transverse sections of parts of a plant. In the transverse sections, which tissues transport sucrose? [Figure 23.1]
Which statement describes movement through a plant in the apoplast pathway?
Which changes to the water potential and the volume of liquid in the phloem occur when sucrose is moved from the phloem sieve tube to an actively d...
The diagram shows the results of an experiment using leaves with the same surface area from two different species of plant. Each leaf was left on a...
Which evidence supports the cohesion-tension theory for the movement of water in flowering plants? 1 When the rate of transpiration of a tree is at...
Cardiac muscle is made up of many fibres that form the walls of the chambers of the heart. When the heart contracts, these fibres shorten in length...
Which reactions take place at a higher rate in a capillary in an alveolus than in a capillary in active muscle? 1 carbon dioxide + water → carbonic...
The diagram shows the effect of three different concentrations of carbon dioxide on the oxygen dissociation curve for human haemoglobin. What effec...
The graph shows the changes that take place in the volume of the left ventricle during one cardiac cycle. Which point on the graph represents the s...
The following tissues carry an electrical impulse during the cardiac cycle. 1 atrioventricular node 2 muscle wall of atria 3 Purkyne tissue 4 sinoa...
Some of the effects of smoking are listed. 1 It causes coughing. 2 It increases blood pressure. 3 It decreases the transport of oxygen. 4 It increa...
The photomicrograph shows a section through part of a bronchus wall. What is the function of the tissue labelled X? [Figure 34.1]
Which of the following increase the risk of contracting TB? 1 drinking unpasteurised milk 2 eating shellfish which have fed on raw sewage 3 living ...
One control method to reduce the spread of malaria is to use an insecticide. It can be used to treat mosquito nets. Another control method is to co...
What is not an example of antibiotic action?
Which row correctly identifies the roles of B-lymphocytes and T-lymphocytes? [Figure 38.1]
A person's blood group is determined by antigens present on the red blood cells. The table shows the antigens and antibodies in the blood of people...
An enzyme hydrolyses the two heavy polypeptide chains of an antibody molecule. The hydrolysis occurs at the hinge region and breaks the antibody in...
The diagram shows the ultrastructure of a typical animal cell. Which structure synthesises and transports lipids? [Figure 1.1]
A light microscope is used to observe two structures that are 200 nm apart. How far apart are the structures when the magnification is changed from...
The diagram shows a stage micrometer scale viewed through an eyepiece containing a graticule. The small divisions of the stage micrometer scale are...
Some features of cells are listed. 1 cytoplasm 2 cell surface membrane 3 ribosomes Which features are found in both animal and prokaryotic cells?
Which size of ribosomes is found in chloroplasts?
In which of these organelles is ATP synthesised? [Figure 6.1]
A sample of milk is tested with Benedict's solution. After boiling, a yellow colour is observed. Which conclusion is correct?
The table shows some information about carbohydrate polymers. Which row describes amylose? [Table 8.1]
Which row about α-glucose and β-glucose molecules is correct? [Table 9.1]
Some of the molecules found in animal tissues are grouped into three lists. 1 glucose, cholesterol, triglycerides, water 2 glycogen, antibodies, ad...
Haemoglobin consists of two α chains and two β chains. Approximately 5% of all humans have one amino acid in the β chain that has been changed, aff...
Which row gives the correct description of both a collagen molecule and a collagen fibre? [Table 12.1]
The diagrams show the structures of two amino acids, each of which has two amine (–NH2) groups. A peptide bond is formed between the two amino acid...
An enzyme was added to a small excess of its substrate. All variables were kept constant. A student was asked to sketch a graph to show how the con...
The table contains results recorded by a student from an investigation into the effect of temperature on an enzyme-catalysed reaction. All other va...
What is the correct range of measurements for the width of the cell surface membrane?
The cells in the roots of beetroot plants contain a red pigment. When pieces of root tissue are soaked in cold water, some of the red pigment leaks...
The cell surface membrane structure is described as a 'fluid mosaic'. Which statement describes the 'mosaic' part of the cell surface membrane?
The diagram shows two pathways, X and Y, through which molecules can diffuse across a cell surface membrane. Which row correctly shows possible pat...
Some stem cells divide and give rise to phagocytes. Where in the human body do these stem cells divide? 1 blood 2 bone marrow 3 lymph nodes
What is the correct sequence of stages in the mitotic cell cycle?
The enzyme telomerase repairs telomeres. It stops the telomeres from getting shorter each time a chromosome is replicated. Telomerase is not normal...
The statements describe events during the mitotic cell cycle. 1 Chromosomes migrate to opposite poles of the spindle. 2 Chromosomes arrange themsel...
Which statement about nitrogenous bases is correct?
Rifampicin is an antibiotic used to treat tuberculosis. It works by inhibiting RNA polymerase in bacteria. Which of these processes will be directl...
Meselson and Stahl investigated DNA in bacteria. They grew bacteria in a medium with only heavy nitrogen, 15N, until all of the bacterial DNA conta...
The diagram shows the stages in the production of part of a polypeptide. Which feature of the triplet code is illustrated by the information given?...