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.
In the sweet pea plant, Lathyrus odoratus, one gene codes for flower colour and one gene codes for pollen grain shape. Flower colour is either purp...
Within a population, the variation for one characteristic is usually the result of genetic and environmental causes.
Adult Drosophila fruit flies feed on yeasts on the surface of ripe fruits. Female flies lay their eggs inside the fruit and the larvae feed inside ...
A severe reduction of blood flow to the brain causes cells to die. This is called a stroke. The after-effects of a stroke can range from recovery t...
Fig. 6.1 is an outline diagram showing two stages of aerobic respiration. [Fig. 6.1]
Fig. 7.1 shows part of a section through the leaf of a C4 plant such as maize. The letters A, B and C show three types of cell found in the leaf. [...
Describe how an action potential arriving at a presynaptic neurone can result in the release of acetylcholine into the synaptic cleft.
Outline the characteristic features of organisms in the domain Archaea.
Describe the process of selective reabsorption and explain how the cells of the proximal convoluted tubule are adapted to carry out selective reabs...
The Sulawesi macaque, Macaca nigra, is found on the large island of Sulawesi in Indonesia. The Sulawesi macaque is also found on other smaller isla...
In the fruit fly, Drosophila melanogaster, eye colour and wing shape are controlled by genes. • E/e are alleles of a gene involved in eye colour. ...
Meiosis is described as reduction division. Explain why meiosis is necessary in the life cycle of a sexually reproducing organism.
A study was carried out to investigate natural selection in the plant evening primrose, Oenothera biennis. Physiological changes associated with r...
People with Alzheimer's disease (AD) lose their ability to form new memories. One form of Alzheimer's disease, called familial Alzheimer's disease,...
Fig. 6.1 is a diagram of part of a mitochondrion showing some of the events occurring in oxidative phosphorylation. [Figure 6.1]
Fig. 7.1 is a transmission electron micrograph of part of a chloroplast of a leaf cell from maize. [Figure 7.1] Table 7.1 shows some substrates a...
Striated muscle is made of many fibres. Each fibre is composed of myofibrils. The striated appearance of the muscle fibre is due to the arrangemen...
Outline the characteristic features of organisms in the domain Eukarya.
Describe the effect of a high blood concentration of ADH on the kidney.
Some students were asked to use leaf discs to investigate photosynthesis in leaves of different types. The students decided to compare the rate of...
The red squirrel is a tree-living mammal native to woodlands in the United Kingdom. The population and distribution of the red squirrel have been d...
During the light dependent stage of photosynthesis, hydrogen ions and electrons are released by the photoactivation of chlorophyll and the photolys...
Red deer are herbivores common in the highlands of Scotland. They have no natural predators and in some areas culling of the deer is carried out in...
Sodium hydrogencarbonate indicator solution contains sodium hydrogencarbonate. Some students found out on the internet that this indicator solution...
Lionfish are a type of fish native to the tropical waters of the Indian Ocean and Pacific Ocean. Lionfish were first reported off the south east co...
The actual length of a cell structure is 8 µm. Which steps are used to calculate the magnification of an electron micrograph of this cell structure...
What is the typical resolution of a microscope using daylight as a light source with a ×10 eyepiece lens and a ×40 objective lens?
Two different types of cell, P and Q, were broken up using ultrasound and their contents analysed. Both types of cell contained small circular DNA....
Which features shown in the diagram can be present in viruses? [Figure: Diagram showing a central 'feature' connected to 1 DNA, 2 protein coat, 3 7...
After boiling a sample of milk with Benedict's solution, a yellow colour is observed. Which conclusion about the sample of milk is correct?
Which of the statements about polysaccharides can be used to describe amylose and cellulose? 1 contains 1,4 glycosidic bonds 2 contains 1,6 glycosi...
Which diagram shows the formation of a peptide bond?
In enzyme-catalysed reactions, the position of the amino acids found at the active site is important. During the synthesis of enzymes, amino acids ...
Which features affect the tensile strength of collagen? 1 the helical structure of collagen chains 2 the small R group of the amino acids in collag...
A fixed volume of the enzyme catalase was added to a fixed volume of hydrogen peroxide solution. The diagram shows how the concentration of product...
A fixed volume and concentration of substrate and enzyme were mixed. All other variables were kept constant. The enzyme-catalysed reaction was left...
The fatty acids elaidic acid and oleic acid have exactly the same structural formulae, with one double bond in the chain. However, the shapes of th...
The diagram shows a cell surface membrane. [Figure: Diagram of cell surface membrane with labelled molecules W, X, Y, Z] Which is a correct role fo...
The diagram shows a simple cell signalling pathway in which a signal molecule leads to a response, such as a secretion. [Figure: Flowchart signal m...
Three parts of a chromosome and their functions are listed. part function P1 centromere F1 holds the coils of DNA together P2 histone proteins F2 h...
The enzyme telomerase prevents loss of telomeres after many mitotic cell cycles. Which cells need to transcribe telomerase enzyme? 1 cancer cells 2...
The diagram shows some of the stages which take place during the cell cycle. [Figure: Flowchart showing cell cycle stages] Which two stages take pl...
Which statement correctly describes the base pairing in a molecule of DNA?
Which statements about complementary base pairing are correct? 1 It allows translation to occur. 2 Purines and pyrimidines are the same size. 3 The...
The diagram shows the possible organisation of DNA molecules after one replication. Which organisation is correct?
The diagram shows part of the DNA sequence of a gene and a mutated sequence of the same gene. normal DNA sequence ...CCG GAT TAT TGC GAG AAA TGG CA...
What is correct for phloem sieve tube elements?
The statements are descriptions of how water moves across the root to the xylem vessel elements. 1 Water enters cell walls. 2 Water enters cytoplas...
Four plants, A, B, C and D, were grown in the same conditions and their transpiration rates measured. [Figure: Graph showing transpiration rate for...
Sucrose moves from a mesophyll cell in a leaf into a phloem sieve tube element. Which changes to the water potential and the volume of liquid in th...