Cambridge Past Paper Questions
Browse 23,045questions from 25 years of O-Level & A-Level exams. Click any question to practice.
After an immune response, memory cells remain in the blood for a long time. What is the function of memory cells?
What are produced by B-lymphocytes?
Scientists are concerned that avian (bird) flu caused by the H5N1 virus, could infect humans and cause a pandemic. If this occurs, which factors co...
A country has fewer than 2.5 deaths per 100 000 people from TB in one year and the next year this rose to 25 deaths per 100 000. What may have cont...
The diagram shows an arctic ecosystem. [Diagram of an arctic food web] How many trophic levels are represented?
A tree carries out photosynthesis and provides organic compounds for other organisms in a forest. It takes carbon dioxide from and returns oxygen t...
In an investigation, discs of 2.5 cm diameter were cut from leaves. Fifty discs were p identical bags with different net sizes and buried in newly ...
Which steps are needed to find the actual width of a xylem vessel viewed in transv using a ×40 objective lens? 1 Convert from mm to µm by multiplyi...
A specimen is viewed under a microscope using green light with a wavelength of 510nm. If the same specimen is viewed under the same conditions, but...
Which cell organelle does not contain nucleic acid?
The diameter of living cells varies considerably. The typical diameters are a eukaryote, such as a white blood cell 1.5 × 10¹ μm a prokaryote, such...
Cells consist of a number of different components. Which row shows the components present (✔) in both a prokaryotic and eukaryotic cell? lysosomes ...
The diagram shows part of a carbohydrate molecule. [Figure 6.1] If all the 1,4 glycosidic bonds in this molecule are hydrolysed, how many water mol...
A peptide bond is formed between atoms of which two elements?
An amino acid can be represented as [Figure 9.1 showing a central carbon atom bonded to N, H, C(=O)OH, and R] where R represents a variable side ch...
When red cells leave the lungs, haemoglobin is 98% saturated. How many molecules of oxygen will be carried by the majority of haemoglobin molecules?
A fixed volume of the enzyme catalase was added to a fixed volume of hydrog solution. The diagram shows how the rate of the reaction changed over t...
The diagram shows the transport of ions across the cell surface membrane. Inside is a low concentration of sodium ions (Na+) and a high concentrati...
Plant cells were immersed in solutions of different water potential and left for one hour. Which row shows the effect of the different solutions on...
Which molecules, found in cell surface membranes, contribute to cell recognition? 1 glycolipids 2 glycoproteins 3 phospholipids
In which process does mitosis not have an important role in living things?
The diagram shows the chromosomes of a typical plant cell at the metaphase stage [Figure 18.1 showing chromosomes arranged at metaphase plate]. Whi...
The table shows the percentages of bases in DNA from various types of cell. [Table showing percentages of adenine, guanine, thymine, cytosine for c...
Which row shows the correct combination? triplet code codon anticodon
A culture of bacteria had all its DNA labelled with the heavy isotope of nitrogen (15N). A sample was taken and spun in a centrifuge. The diagram s...
S and T are products of a biochemical pathway. A different enzyme, coded for specific genes, catalyses each step in the pathway. [Figure 22.1 showi...
Which processes are involved in transpiration? 1 the diffusion of water vapour from stomata 2 the mass flow of water through the xylem 3 the evapor...
What is the main function of a companion cell in mature phloem tissue?
Water passes across leaf tissues by different routes as a result of • differences in water potential • the pull transmitted by cohesive forces betw...
The diagram shows a transverse section of a stem. [Figure 26.1 showing a TS of a stem with regions A, B, C, D labeled] Which area is the phloem?
The diagram shows the water potential (Y) in some plant cells and in their environment. [Figure 27.1 showing three plant cells and environment with...
In mammals, some carbon dioxide is transported by red blood cells in combination with haemoglobin. What is the product of this combination?
The graph shows pressure changes during a cardiac cycle. [Figure 30.1 showing a graph of pressure vs time with points W, X, Y, Z] Which row correct...
Some babies are born with a hole between the right and left atria. These newly born babies are found to have an increased number of red blood cells...
Which row correctly shows the areas of the respiratory tract that contain cartilage, epithelium), goblet cells and smooth muscle? cartilage cilia g...
Which of the effects listed occur as a result of inhaling both carbon monoxide and nicotine from cigarette smoke? 1 increased heart rate 2 increase...
During an investigation on gas exchange, three measurements were made on four efficiency of gas exchange was the same in all four people. Which per...
The data shows how the number of human deaths caused by the bacterium Staphylococcus aureus has changed from 1997 to 2005. Methicillin is an antibi...
The diagram shows the response to a pathogen by the immune system. [Figure 38.1 showing an immune response pathway with P, Q, R, S] Which row corre...
The diagram represents part of the nitrogen cycle. [Figure 39.1 showing a nitrogen cycle diagram with processes A, B, C, D labeled] Which process i...
The diagram shows the flow of energy between organisms in an ecosystem. [Figure 40.1 showing an energy flow diagram with organisms 1, 2, 3, 4] Whic...
Where would cisternae be found in a cell? 1 endoplasmic reticulum 2 Golgi apparatus 3 mitochondrion
Ribosomes exist as separate subunits that bind together during protein synthesis. What do these subunits consist of?
Which cell components contain mRNA? 1 chloroplast 2 mitochondrion 3 nucleus 4 rough endoplasmic reticulum
The diagram shows a stage micrometer on which the small divisions are 0.1 mm. through an eyepiece containing a graticule. [Figure 5.1] The stage mi...
Which processes occur in eukaryotes and prokaryotes? 1 hydrolysis 2 mitosis 3 transcription 4 translation
High concentrations of urea break all bonds, except covalent bonds, in protein molecules. Which level of protein structure would remain unchanged w...
Two disaccharides are cellobiose and sucrose. Cellobiose is formed from two molecules of glucose, whilst sucrose is formed from fructose and glucos...
The diagram shows part of a carbohydrate molecule. [Figure 9] Which polymers could this be part of? 1 amylopectin 2 amylose 3 glycogen 4 starch
When a lake begins to freeze, which properties of water are needed for fish to survive? 1 Water has a high surface tension. 2 Water has a high lat...