Cambridge Past Paper Questions
Browse 23,045questions from 25 years of O-Level & A-Level exams. Click any question to practice.
The statements are all descriptions of cell structures. 1 surrounded by a single membrane and enclosing a large fluid-filled space 2 surrounded by ...
Which structures are found in both typical eukaryotic cells and typical prokaryotic cells? 1 70S ribosomes 2 80S ribosomes 3 circular DNA
Which sequence shows some of the stages in the production and secretion of an enzyme?
Which plan diagram of a transverse section of a dicotyledonous leaf correctly shows the position of xylem and phloem in a palisade mesophyll layer ...
Proteases are a group of enzymes that digest proteins. Which statement about proteases is correct?
Two disaccharides are maltose and sucrose. Maltose is formed from two molecules of glucose whilst sucrose is formed from fructose and glucose. Whic...
The diagram shows a carbohydrate molecule. [Figure 9] Of which polymers could this be a part?
Which of the bonds stabilising the tertiary structure of a protein would be least likely to break when the temperature is increased above the optim...
The diagram shows the structure of four amino acids in solution. [Figure 11] Which amino acids have no overall charge?
The statements are about the properties of water. 1 It requires a lot of heat to evaporate. 2 It retains a lot of heat. 3 It is able to form hydrog...
Which words from the table correctly complete the paragraph about enzymes? When the pH of an environment is decreased below an enzyme's optimum pH,...
Lipase is a digestive enzyme produced by the pancreas that catalyses the hydrolysis of dietary lipids. The table shows how the pH of a liquid food ...
The AIDS virus produces a long polypeptide that is hydrolysed by a protease enzyme to several smaller peptides. This viral protease is the target o...
What is the width of the cell surface membrane?
Some functions of molecules found in cell surface membranes are listed. 1 cell recognition 2 ion transport 3 maintaining fluidity 4 mechanical stab...
The enzyme lactase is found in the membranes of epithelial cells lining the small intestine. The enzyme is formed by a single polypeptide that fold...
A student examined the cells in the growing region (meristem) of an onion root and recorded the data below. [Figure 19] What percentage of cells co...
Which definitions of diploid and haploid are true for typical eukaryotic cells? 1 diploid – any cell with an even number of homologous chromosomes ...
Which type of sugar and types of bonds are found in a DNA molecule?
Which nucleic acid bases are purines?
A short piece of DNA 15 base pairs long was analysed to find the number of nucleotides in each of the polynucleotide strands. Some of the results a...
The diagram shows a transverse section of a stem. [Figure 24] Which area is the phloem?
A leafy shoot was attached to a potometer and exposed to a variety of conditions. The time taken for the meniscus to move 50 mm along the capillary...
The diagram shows four plant cells. [Figure 26] In which direction could there be net movement of water by osmosis?
How will the root pressure in a plant be affected by waterlogged soil?
Small arteries (arterioles) are found near tissues. One function of an arteriole is to increase or decrease the flow of blood to the tissues. Which...
The graph shows a dissociation curve for haemoglobin. [Figure 30] Which are suitable labels for the x-axis and the y-axis?
One type of congenital heart defect is called atrial septal defect (ASD) where the left and right atria are not completely separated. ASD usually r...
Which are effects on the body of carbon monoxide in tobacco smoke? 1 It reduces the amount of haemoglobin available to transport oxygen. 2 It reduc...
The graph shows the volume of air breathed out quickly and with force, following a deep breath in, for three different people, X, Y and Z. [Figure ...
Which statements about people infected with HIV/AIDS are correct? 1 They can be treated and completely cured. 2 They may live for many years after ...
The statements refer to polio and tuberculosis (TB). 1 Macrophages present antigens in vaccines to stimulate an immune response. 2 The TB antigens ...
Which explains why sickle cell anaemia has not been eradicated?
Which method of gaining immunity can be described as natural active immunity?
Which stage of energy transfer has the lowest efficiency?
The diagram shows a simplified nitrogen cycle. [Figure 40] During which stage does decomposition take place?
Which size of ribosome is found in mitochondria?
Different units are used when measuring biological specimens. Which measurement in mm has not been correctly converted into both µm and nm?
Which features of microvilli and root hairs are correct?
Lysosomes have a variety of different shapes and sizes, making them difficult to identify. What describes a lysosome?
Radioactively-labelled amino acids were introduced into a tracheal cell that uses them to make mucus (a glycoprotein). [Figure 5.1] What route will...
Which structures are present in a Vibrio cholerae cell? [Figure 6.1]
The colour of a positive Benedict's test is due to the formation of copper oxide. The mass of copper oxide is proportional to the mass of reducing ...
Which diagram shows the bond linking the individual units of both cellulose and glycogen?
Which row describes a triglyceride?
The diagrams show the amino acid serine. Which circled area is different in all other amino acids?
Which statements describe some enzyme actions? 1 Enzymes hold reacting molecules in such a way that their reactive groups are brought close togethe...
The diagram shows the mass of product formed over time in three reactions using the same substrate and enzyme. The volumes of substrate, enzyme and...
Tyrosinase is an enzyme that catalyses the conversion of the amino acid tyrosine into the black pigment melanin. It is responsible for the black fu...
Which descriptions are correct for transport across cell surface membranes?