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.
Photosynthesis is an energy transfer process that takes place in chloroplasts of plant cells. [Figure 3.1, Figure 3.2]
Haemophilia is a blood clotting disorder in humans caused by a mutant allele on the X chromosome. Table 4.1 compares two forms of haemophilia: haem...
Myosotis is a genus of small flowering plants. Many different Myosotis species grow on the islands of New Zealand, which are an important site of M...
The lac operon of prokaryotes contains a group of structural genes that are under the same control and are transcribed together. Another operon fou...
The determination of sex in domestic turkeys is different from that in humans. The sex chromosomes in turkeys are named Z and W. Male turkeys are Z...
Selective reabsorption takes place in the proximal convoluted tubule of a kidney nephron. Fig. 8.1 is a diagram of two cells of the proximal convol...
Voltage-gated channels are involved in the generation of an action potential. Fig. 9.1 is a diagram of the voltage-gated channels of sodium ions an...
Glucagon has a role in the maintenance of blood glucose concentration. Fig. 10.1 shows the relationship between blood glucose concentration and blo...
(a) Fig. 8.1 is a diagram of a kidney nephron. [Figure 8.1] [Figure 8.2]
Antibiotic resistance in bacteria is a global problem that has caused scientists to research into antibacterial substances other than antibiotics. ...
Holstein cattle have been selectively bred for their high milk production. The seed of the cotton plant, Gossypium spp. is a good source of fibre,...
Egg albumen (egg white) is a good source of protein. Some eggs contain up to 10.0% w/v (100gdm-³) protein. A biuret assay can be used to determine...
A main feature of Huntington's disease (HD) is a loss of neurones from a region of the brain known as the striatum. A study of brain tissue taken f...
Holstein cattle have been selectively bred for their high milk production. The seed of the cotton plant, Gossypium spp. is a good source of fibre, ...
The diagram shows an electron micrograph of virus particles in a human nucleus. [Figure 2.1] What is the diameter of the labelled virus particle?
What is correct about the synthesis and release of the glycoprotein mucin in goblet cells? 1 The protein is produced on ribosomes and a carbohydrat...
What are functions of microtubules? 1 allowing movement of cilia in a bronchus 2 attachment to centromeres during metaphase 3 moving secretory vesi...
Which organelles contain nucleic acids? [Figure 5.1]
Which bonds are present in all viruses? 1 phosphodiester 2 peptide 3 covalent
A student carried out the Benedict's test on four different concentrations of glucose solution and then recorded the time taken for the first appea...
Which statements about amylopectin and glycogen are correct? 1 Amylopectin and glycogen contain 1-4 glycosidic bonds. 2 Amylopectin contains ẞ-gluc...
How many statements about fatty acids are correct? • Fatty acids are either saturated or unsaturated. • Fatty acids always have at least two double...
The diagram represents an amino acid. [Figure 11.1] R represents a variable side chain. What is not a possible side chain?
The graph shows the effect of an enzyme on a reaction. [Figure 12.1] Which row identifies X, Y and Z?
The graph shows the results of two experiments on the effect of increasing substrate concentration on the rate of an enzyme-catalysed reaction. One...
Which statements about the Michaelis–Menten constant (Km) of an enzyme are correct? 1 At the Km value, half the active sites of the enzyme should b...
Which component of cell surface membranes helps to reduce fluidity of the phospholipids at high temperatures?
Plant cells were left for 50 minutes in three different sugar solutions, 10%, 5% and 1%. The water potential in the cytoplasm of the three cells wa...
The graph shows the effect of increasing the side length of agar cubes on the surface area and the volume of the cubes. [Figure 17.1] Which row cor...
A human embryo consists of 12 cells at the start of day 1. The cells divide by mitosis for 4 complete days at a rate of 1 division every 32 hours. ...
Which diagrams show roles of mitosis? [Figure 19.1]
Which events are part of the mitotic cell cycle? 1 interphase 2 anaphase 3 cytokinesis
Which statement correctly describes a feature of a DNA molecule?
Which diagram correctly shows the replication of DNA? [Figure 22.1]
The RNA codon wheel is a tool used to find which amino acid would be translated from an mRNA sequence. [Figure 23.1] Codon position 1 is in the cen...
Four students sketched diagrams of the apoplast pathway and the symplast pathway. Which sketch is the most accurate diagram of the two pathways? [F...
The photomicrograph shows some xerophytic adaptations in leaf tissue. [Figure 25.1] Which row shows the correct functions for structures 1, 2 and 3?
Which processes are required for the transfer of assimilates from a source cell into a phloem sieve tube?
When sucrose is loaded into the phloem it has to travel from mesophyll cells to a companion cell and then into the phloem. Which row shows the rela...
Which feature of transport in plants is correct for xylem and phloem?
The diagram shows an anterior view of a vertical section through the human heart. [Figure 29.1] Which row shows the correct labels for the diagram?
What does the inner layer of veins and capillaries contain?
The graph shows the changes in blood pressure and water potential across a blood capillary from the arterial end of the capillary to the venous end...
Which statement is correct about a red blood cell that has just entered a capillary in a respiring muscle?
The graph shows some blood pressure changes that occur in a human during one cardiac cycle. [Figure 33.1] When does systole start and end in the ri...
Which statements about all bronchioles are correct? 1 They have goblet cells. 2 They have epithelial cells. 3 They have muscle tissue.
What is shown in the electron micrograph? [Figure 35.1]
Which statement correctly describes infectious diseases?
Organism X produces molecule Y, which blocks the activity of 70S ribosomes. An experiment was carried out to investigate the effect of Y on bacteri...
A patient has had repeated infections from the same pathogen over a few months. The patient has been treated with the same antibiotic on each occas...