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.
Which of the following statements are true of all enzymes? 1 soluble in water 2 catalyse the breakdown of large molecules into smaller molecules 3 ...
The graphs show the effects of temperature and pH on enzyme activity. [Figure: Two graphs, one of rate of reaction vs temperature with points P and...
The diagram shows part of a cell surface membrane. [Figure: Diagram of a cell surface membrane with labelled components 1, 2, 3, 4, 5] Which molecu...
Increasing which type of bond helps to increase the fluidity of the cell surface membrane?
When cylinders of potato tissue were immersed in a 0.35 mol dm-³ sucrose solution, they showed no change in mass. What will happen when cylinders a...
The graph represents the changes in the quantity of DNA present in one nucleus at different stages in the life cycle of a mammal. [Figure: Graph sh...
At which stage of mitosis do these events occur? [Figure: Table with columns 'centromeres separate' and 'spiralisation and condensation of DNA']
During which process does only mitosis occur?
The table shows the tRNA anticodons for four amino acids. [Figure: Table showing amino acid and corresponding tRNA anticodon] A cell makes a polype...
What does the enzyme RNA polymerase synthesise?
The diagram shows part of a DNA molecule. [Figure: Diagram of a DNA double helix with bases A, T, G, C labelled on strands] How many hydrogen bonds...
Which features enable the aorta to withstand high pressure at ventricular systole?
There is a decreased partial pressure of oxygen at high altitude compared to sea level. Which row is a correct description and reason for the respo...
What events occur during contraction of the left ventricle?
Blood, tissue fluid and lymph each have a different composition. Which row shows the composition of lymph? [Figure: Table with columns 'contains wa...
Which processes are involved in transport in both phloem and xylem? 1 diffusion 2 mass flow 3 osmosis
Which features of xerophytes are adaptations to reduce water loss by transpiration? [Figure: Table with columns 'rolled leaves', 'fleshy leaves', '...
The graph shows the results of measuring the concentration of sucrose in the xylem, phloem and leaves of a plant during 24 hours. [Figure: Graph sh...
Water that is present inside a root hair cell may leave the cell and pass to the xylem. Through which pathway must the water travel?
What are the approximate diameters of a trachea, an alveolus, a bronchiole and a bronchus? [Figure: Table with columns 'trachea/mm', 'alveolus/mm',...
What could occur as a result of inhaling the nicotine in tobacco smoke?
Which effects does emphysema have? 1 surface area to volume ratio of lungs decreases 2 distance of the diffusion pathway increases 3 volume of oxyg...
Which of the diseases listed in the table are only treatable using antibiotics? [Figure: Table with columns 'cholera', 'measles', 'TB' and symbols ...
The diagram shows properties of diseases. [Figure: Venn diagram with circles 'bacterial', 'infectious', 'transmitted by airborne droplets' and labe...
The disease smallpox has been eradicated by a worldwide vaccination programme. Which set of reasons correctly identifies the problems associated wi...
Anaerobic bacteria are abundant in waterlogged soils. Which effect does this have on soil fertility and why? [Figure: Table with columns 'soil fert...
What name is given to all the organisms in an area and their interactions with their environment?
What is the function of nitrifying bacteria in the soil?
Which range of sizes would include most eukaryotic cells?
A student was asked to draw a plan diagram of the plant tissue shown in the photomicrograph and to annotate two observable features. [Figure 2.1] W...
Which structure is present in all eukaryotic cells but not present in prokaryotic cells?
What restricts the resolution of the light microscope?
The diagram shows an electron micrograph of virus particles in a human nucleus. [Figure 5.1] What is the diameter of the labelled virus particles?
A student carried out a series of tests on an extract from a plant. The table shows the results of the tests. [Table 6.1] Which row shows the molec...
Glycogen is a polymer of glucose. Which description summarises its structure?
Which molecules contain C=O bonds? 1 amino acids 2 fatty acids 3 proteins
Which of the statements about polysaccharides can be used to describe both amylose and amylopectin? 1 contains 1,4 glycosidic bonds 2 contains 1,6 ...
Which carbohydrate gives a brick red colour when heated with Benedict's solution?
The diagram shows two molecules of glucose. Four possible bonding positions are labelled p, q, r, and s, and t, u, v, w. [Figure 11.1] When these t...
Which graph represents the changes in concentration of a substrate and its product in the same enzyme-catalysed reaction?
Glucose in urine can be detected using a biochemical test. When the end of a test strip, which is impregnated with the enzyme glucose oxidase, is d...
What is the role of cholesterol in the cell surface membrane?
The following are all processes by which substances can enter a cell. 1 endocytosis 2 facilitated diffusion 3 osmosis Which processes are passive?
The diagram shows the water potential of three adjacent plant cells. [Figure 16.1] In which directions will there be net movement of water by osmosis?
Each of the following events takes place during mitosis. 1 centromeres divide 2 chromatids move to opposite poles of the cell 3 chromosomes line up...
The diagram shows the cell cycle. [Figure 18.1] When radioactive nucleotides are supplied to dividing cells, at which point will they be incorporat...
What does the process of transcription require?
A peptide consists of ten amino acids of four different kinds. What is the theoretical minimum number of different tRNA molecules required to trans...
Which statements about tRNA structure are correct? 1 There is a binding site for the attachment of a specific amino acid, as well as a different bi...
Which statements describe why a large animal has had to evolve a transport system? 1 diffusion occurs slowly over long distances 2 it has a high ra...