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 of these substances can pass directly through cell surface membranes without using a carrier protein or a channel protein? 1 Ca²⁺ 2 CO₂ 3 C₆H...
Companion cells use ATP to move hydrogen ions out of the cell and co-transporter proteins to allow hydrogen ions to return with sucrose molecules. ...
How many copies of each different DNA molecule will be found in a cell at the start of each of these stages of the mitotic cell cycle? [Table showi...
Three parts of a chromosome and their functions are listed. part P1 centromere P2 histone proteins P3 telomere function F1 packages DNA into compac...
The graphs show various distance measurements taken from metaphase of mitosis onwards. The graphs are to scale when compared to one another. [Figur...
A culture of bacteria was allowed to reproduce using nucleotides containing the heavy isotope of nitrogen (¹⁵N). After several generations, all of ...
The diagram represents a molecule of ATP. [Figure showing ATP molecule with parts P, Q, R labelled] What are the components of ATP labelled P, Q an...
The table shows three anticodons for different amino acids. [Table showing amino acid and anticodon] Which DNA triplet on the DNA template strand c...
The photomicrograph shows a transport tissue in the stem of a grape vine. [Photomicrograph with T labelled] What is the structure labelled T?
The diagrams show transverse sections of parts of a plant. Transport tissues are labelled 1 to 6. [Figures showing transverse sections of leaf, ste...
What will increase the rate of transpiration? 1 increasing the humidity 2 increasing the light intensity 3 decreasing the temperature 4 decreasing ...
Which properties of water are important for transport in xylem? 1 cohesion 2 adhesion 3 high energy requirement for evaporation 4 good solvent prop...
Which statement about the blood flow in the cardiac cycle is correct?
Which of these statements about the formation of haemoglobinic acid are correct? 1 It depends on the formation of carbaminohaemoglobin. 2 It remove...
What can combine with the haem group of a haemoglobin molecule? 1 oxygen 2 carbon dioxide 3 carbon monoxide
Which factors would help a person to adjust from living at a low altitude to living at a high altitude? 1 formation of fewer red blood cells 2 an i...
Chronic obstructive pulmonary disease (COPD) includes bronchitis and emphysema. Which symptom is specific to emphysema?
What identifies the structures present in a bronchus? [Figure showing a Venn diagram with circles for cartilage, cilia, goblet cells, and regions A...
Which of these terms can be used to describe the role of mosquitoes in the transmission of malaria? 1 malarial parasite 2 pathogen 3 vector
Bacteria that infect skin wounds can become resistant to the antibiotic commonly used to kill them. Which statement explains how these bacteria cou...
Some children are born with severe combined immunodeficiency (SCID). Children with this inherited disease do not normally have any T-lymphocytes an...
The hybridoma method is used for the production of monoclonal antibodies. Which two types of cell are used in this method?
A vaccine is used to create artificial active immunity. After being given a vaccine, it will take a period of time before a person develops long-te...
Fig. 1.1 is an electron micrograph of part of a eukaryotic cell. [Figure 1.1]
The main cause of tuberculosis (TB) in humans is the bacterium Mycobacterium tuberculosis. Most cases of the disease involve the lungs. The bacteri...
The unicellular fungus Kluyveromyces lactis is found in dairy products. It is a safe microorganism to culture for the extraction of the enzyme lact...
Fig. 4.1 is a diagram of a section through part of a young root. [Figure 4.1]
The sinoatrial node (SAN) and the atrioventricular node (AVN) are two regions of the heart. Fig. 5.1 shows features that are observed in transverse...
In a dividing cell, DNA replication occurs before mitosis. Steps in DNA replication are outlined in Fig. 6.1. [Figure 6.1]. Fig. 6.2 is a photomicr...
Mung bean seeds contain an enzyme that is used to hydrolyse (break down) sucrose into reducing sugars. This enzyme is essential to provide the redu...
P1 is a slide of a stained transverse section through a plant leaf. You are not expected to be familiar with this specimen. You are required to: • ...
The aye-aye, Daubentonia madagascariensis, is a primate native to Madagascar. Aye-ayes are nocturnal (active at night) and make their nests high up...
Motor neurones are cells within the nervous system.
The ẞ-globin gene codes for the ẞ-globin polypeptide of haemoglobin. It has two alleles, HbA (normal) and Hbs (sickle cell). The sickle cell allele...
Ribulose 1,5-bisphosphate carboxylase/oxygenase (rubisco) is an important enzyme involved in the light independent stage (Calvin cycle) of photosyn...
The contraction of striated muscle is explained by the sliding filament model.
The black pigment melanin, which contributes to hair, skin and eye colour, is produced by cells known as melanocytes.
Fig. 7.1 shows a red deer, Cervus elaphus. Red deer are herbivores that feed on a wide range of plants. [Figure 7.1] The number of red deer in the ...
Structures and compounds involved in respiration include: 1 coenzyme A 2 cytoplasm 3 pyruvate 4 NAD 5 outer mitochondrial membrane 6 carrier protei...
Describe the process of cyclic photophosphorylation and the structure of the photosystem involved.
Explain the role of auxin in cell elongation.
Biological washing liquids are solutions that contain enzymes to help remove stains caused by biological molecules. One of these enzymes is lipase....
The eye has sensory receptors that convert light energy into nerve impulses. The ability of the human eye to detect separate stimuli one after anot...
The diagram below was drawn from an electron micrograph of an animal cell. [Figure shows an electron micrograph of an animal cell.] Which diagram w...
The diameter of a red blood cell in a diagram was measured as 2.5 cm. The actual diameter of the red blood cell was 7 µm. Which calculation would g...
The diagram shows a fin whale drawn to scale. [Figure shows a fin whale with a scale bar of 3m.] A student made three statements about the diagram....
Which structures are found in both chloroplasts and mitochondria? 1 70S ribosomes 2 80S ribosomes 3 circular DNA
Radioactively labelled amino acids are introduced into a cell that is actively secreting an enzyme. In which cell structure will the radioactivity ...
Ribosomes exist as separate subunits that are bound together during protein synthesis. What do these subunits consist of?
Four solutions were tested with Benedict's solution. The table shows the colour of the solutions after testing. [Table with solution number and col...