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.
Therapeutic proteins are used to treat disease. The first purified therapeutic protein used was insulin, in 1922. The insulin was extracted from an...
Meiosis has an important role in sexual reproduction. Meiosis occurs during gametogenesis in humans and during the formation of pollen grains and e...
Fig. 5.1 shows the seaweed *Laminaria hyperborea*. This is a photosynthetic protoctist found in the coastal waters around Norway. The seaweed is gr...
The genus *Heliconius* contains more than 40 species of brightly patterned butterflies. Researchers have investigated in the laboratory how one spe...
The Venus fly trap, *Dionaea muscipula*, is a carnivorous plant, native to wetlands of the East Coast of the USA. Mineral ions from decayed organis...
The passage below outlines the process of oxidative phosphorylation in mitochondria. Complete the passage by using the most appropriate scientific ...
The stickleback fish, Gasterosteus aculeatus, has two distinct forms, the saltwater form and the freshwater form. The larger, freshwater form is th...
Fig. 5.1 shows the seaweed Laminaria hyperborea. This is a photosynthetic protoctist found in the coastal waters around Norway. The seaweed is grow...
The genus Heliconius contains more than 40 species of brightly patterned butterflies. Researchers have investigated in the laboratory how one speci...
The Venus fly trap, Dionaea muscipula, is a carnivorous plant, native to wetlands of the East Coast of the USA. Mineral ions from decayed organisms...
(a) Compare the characteristic features of members of the kingdoms Fungi and Animalia. [7] (b) Discuss the methods used in breeding programmes for ...
(a) Describe the features of ATP that make it suitable for its role as the universal energy currency of cells. [6] (b) Describe how you would carry...
1 (a) Fig. 1.1 shows part of a guard cell. [Figure 1.1] (b) With reference to Fig. 1.1, outline the events that occur in a guard cell during times ...
2 (a) The house mouse, Mus musculus, has a diploid number of 40 chromosomes. Fig. 2.1 shows 6 of these chromosomes. [Figure 2.1] (b) Fig. 2.2 shows...
3 Therapeutic proteins are used to treat disease. One example of a therapeutic protein is human growth hormone (hGH). hGH has important roles in gr...
4 A 28-year study of Magellanic penguins, Spheniscus magellanicus, found in Argentina, provides evidence of natural selection. Magellanic penguins ...
5 Mimulus is a plant genus containing a diverse range of species that have colourful flowers to attract pollinators, such as bees and hummingbirds....
6 Mining may result in the release of heavy metal ions, causing pollution of lakes and rivers. High concentrations of these heavy metal ions, such ...
7 (a) Gibberellin is involved in the germination of barley seeds. In an investigation, aleurone layers from barley seeds were extracted. One sample...
8 The passage below outlines the structure of the mitochondrion. Complete the passage by using the most appropriate scientific term(s). The mitocho...
9 (a) Viruses are not included in the three domain classification system as they have different features from most organisms. Describe the features...
10 (a) Describe the roles of the neuromuscular junction, transverse system tubules (T-tubules) and the sarcoplasmic reticulum in stimulating contra...
Chlorella is a photosynthetic, single-celled protoctist that lives in ponds. A group of students decided to investigate the effect of temperature o...
A fungal pathogen infects melon plants and causes the leaf cells to lose turgor. The melon plant then becomes permanently wilted.
A group of students investigated the growth of different varieties of yeast. The students learned that the rate of respiration in a yeast culture i...
Populations of European ash trees, Fraxinus excelsior, are susceptible to a chronic tree disease called ash dieback. Since 2012, this disease has s...
The size of the measles virus, Morbillivirus, is approximately 150 nm. The Mimivirus is approximately 4.5 times larger than Morbillivirus, whilst t...
The electron micrograph shows a type of virus at a magnification of ×60000. [Figure 2.1] What is the actual length of the virus?
The electron micrograph shows a structure found in the cytoplasm of an animal cell. [Figure 3.1] Which biological molecules are found in this struc...
Which are found in typical prokaryotic cells and in typical plant cells? 1 cell wall 2 circular DNA 3 cytoplasm
The diagram shows some features that occur in organisms. [Figure 6.1] Which features can be present in viruses?
Diastase is an enzyme that breaks down starch into maltose. Maltose is a reducing sugar. A sample of starch is treated with boiled diastase and lef...
Which pair of monosaccharides forms sucrose? [Figure 8.1]
The diagram shows the structures of two amino acids. [Figure 9.1] These amino acids will form part of a protein that has a tertiary structure. Whic...
Which row about the structure of proteins is correct? [Figure 10.1]
Which row correctly identifies structural features of a collagen molecule and a haemoglobin molecule? [Figure 11.1]
Which statements describe some enzyme actions? 1 Enzymes hold reacting molecules so that their reactive groups are close together. 2 In an enzyme-c...
Lipase is an enzyme that catalyses the hydrolysis of lipids. An experiment was carried out to investigate changes in pH when lipase is added to a f...
The painkiller ibuprofen reduces the activity of an enzyme involved in the production of prostaglandin. Ibuprofen binds reversibly to the active si...
Equal-sized potato pieces were placed into test-tubes containing equal volumes of different concentrations of sucrose solution and left for 30 minu...
Four agar blocks are stained green using universal indicator and suspended in 1 moldm⁻³ hydrochloric acid. [Figure 16.1] The time taken for the aga...
During the cell cycle, the mass of DNA in a cell is doubled. At which stage in the cell cycle is the mass of DNA in a cell reduced?
In eukaryotes, the chromosomes become shorter and thicker during mitosis. The thickening may be increased by molecules called protamines. The prota...
How many hydrogen bonds are holding the two strands of this section of a DNA molecule together? [Figure 20.1]
Which description of a eukaryotic gene is correct?
The DNA sequence CCAAGAAGTCGACAAACA is translated to synthesise the amino acid chain gly-ser-ser-ala-val-cys. As a result of a mutation, the sequen...
Which combination of features is correct for a phloem sieve tube element as it unloads into a sink? [Figure 23.1]
Mass flow is the bulk movement of materials from one place to another. Which vessels carry fluids by mass flow? 1 artery 2 phloem sieve tube 3 vein...
Which two rows are correct for the movement of water from the soil into a root? [Figure 25.1]
ATP is used in companion cells to provide the energy for loading a sieve tube element with sucrose. How does the co-transporter mechanism use this ...