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 statements about chronic obstructive pulmonary disease (COPD) are correct? 1 The disease can often be reversed by treatment. 2 The patient's ...
Which of these causative agents of disease can be transmitted by droplet infection? 1 Vibrio 2 Mycobacterium 3 Morbillivirus
The table compares total antibiotic use (X) and the percentage of antibiotic-resistant pneumonia cases (Y) in five countries. [Figure 36.1] What is...
Which statement about the development of resistance to antibiotics in bacteria is correct?
A blood cell count can indicate how many white blood cells there are in the blood. Where else in the body are white blood cells found? 1 bone marro...
Myasthenia gravis is a disease that results from the immune system failing to distinguish between self and non-self. Antibodies bind to a component...
A monoclonal antibody, specific for a virus, was treated with an enzyme to break the bonds between the variable and constant regions. The separated...
Answer all questions. 1 Fig. 1.1 shows five biological molecules. [Figure 1.1]
2 Fig. 2.1 shows some stages of the cell cycle in the meristematic tissue in the root tip of a plant. Three of these stages, P, Q and R, are identi...
3 The enzyme glucose 6-phosphate dehydrogenase (G6PD) is composed of two identical polypeptide chains. (a) Students investigated the activity of tw...
4 Fig. 4.1 shows the site of gas exchange in the mammalian lung. [Figure 4.1]
5 The vaccine used to control tuberculosis (TB) is known as Bacillus Calmette-Guérin (BCG). The vaccine contains live bacteria that have been selec...
6 Fig. 6.1 shows the formation of a polypeptide during translation in a eukaryotic cell. [Figure 6.1]
Picornaviruses are small viruses that are 30 nm in diameter. Picornaviruses are able to enter the cells of mammals and birds and can replicate with...
In a healthy mammalian heart, contraction of the four chambers is coordinated by the action of the sinoatrial node (SAN) and atrioventricular node ...
The Bacillus Calmette-Guérin (BCG) vaccine is the only vaccine used to provide protection against the infectious bacterial disease tuberculosis (TB...
Collagen is a major component of the cartilage found in some of the structures of the human gas exchange system. Cells that synthesise and secrete ...
In most plants, sucrose is the main sugar that is transported from sources to sinks. Fig. 5.1 shows part of one pathway that is used in plant cells...
The mitotic cell cycle in dividing cells is very carefully controlled. Some of the stages have been completed for you. At various points during the...
Water and mineral ions are transported up the stem of a plant to the leaves within xylem vessels. Some water and mineral ions can pass out of xylem...
In 2016, the highest number of cases of malaria and deaths caused by the disease were in sub-Saharan Africa. In many areas of sub-Saharan Africa, m...
Fig. 3.1 is a photomicrograph of a section through two different types of blood vessels, X and Y. [Figure 3.1] Name the two types of blood vessel s...
Saccharomyces cerevisiae is a unicellular fungus that is important in the brewing and baking industries. Fig. 4.1 is a diagram of a transmission el...
Blood cells are formed from tissue stem cells in the bone marrow. These bone marrow stem cells go through a number of mitotic cell cycles to form t...
A student carried out an investigation to estimate the water potential of potato tissue. The main steps in the procedure and in the analysis of res...
Invertase is an enzyme found in honey. Invertase breaks down sucrose into reducing sugars, as shown in Fig. 1.1. sucrose invertase reducing sugars ...
Water moves through xylem vessel elements in plants. The diameter of xylem vessel elements varies between different species of plant. You will meas...
Energy drinks contain a high concentration of carbohydrates, such as glucose, as a source of energy. Glucose is a monosaccharide which can be quick...
In mammals, the hormone ACTH is released from the anterior pituitary gland. ACTH stimulates the cells of the adrenal glands to synthesise the hormo...
The patty pan squash plant, Cucurbita pepo, produces edible fruits that vary in colour. (a) The colour of the fruits is controlled by two genes, A/...
Cats are members of the Felidae family. Two genera of Felidae are Leopardus and Panthera. (a) The genus Leopardus consists of species of wild cats ...
Mitochondrial complex I is a large enzyme complex that forms part of the electron transport chain. The enzyme is composed of many different polypep...
Yeast cells are unicellular eukaryotes. Yeast cells respond to changes in the concentrations of the sugars galactose and glucose by switching on ge...
(a) At the end of glycolysis in mammalian muscle tissue, pyruvate is formed. Pyruvate can be further metabolised along two different pathways, path...
(a) Structures, processes and compounds involved in photosynthesis in C4 plants include: A - carbon dioxide B - phosphorylation C - palisade cells ...
(a) Sampling is used to find out the variety of species in an ecosystem and the size of the population of each species. A study was carried out to ...
Describe how the polymerase chain reaction is used to clone and amplify DNA.
Describe the ultrastructure of a striated muscle fibre.
The enzyme alanine transaminase (ALT) is found in the liver. The function of ALT is to convert the amino acid α-ketoglutarate into another amino ac...
The summer squash plant, Cucurbita pepo, produces edible fruits that vary in shape. [Figure 2.1] shows the fruits of three different varieties of s...
A subspecies is a genetically distinct population within a species that has some phenotypic differences from the rest of the species, but is not ye...
Gene therapy can be used to treat some genetic disorders. An appropriate vector is chosen to carry the normal allele into the target cell. Three ty...
Yeast cells respond to changes in glucose concentration in their environment by using transcription factors to switch off genes. When glucose is pr...
Thyrotoxic myopathy (TM) is a neuromuscular disorder caused by overproduction of the thyroid hormone thyroxine. One of the main symptoms of TM is m...
Define the term respiratory quotient (RQ).
Most organisms are classified according to a taxonomic hierarchy. The hierarchy is shown in [Figure 8.1] but the group names are not in the correct...
The courgette plant, Cucurbita pepo, produces edible fruits that vary in colour and shape. Fruit colour in courgettes is controlled by the gene A/a...
Diabetes insipidus (DI) is a condition in humans that causes a person to have an excessive thirst, which leads to increased drinking. One form of D...
The collared flycatcher, Ficedula albicollis, and the pied flycatcher, F. hypoleuca are two closely related species of bird. DNA analysis has shown...
Lung epithelial cells have a thin layer of watery mucus on their surface. The normal allele of the CFTR gene codes for a transport protein that tra...