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.
Why is the mammalian circulatory system described as a double circulation?
Which sequence of letters correctly identifies the order of events during the cardiac cycle? T atrial walls contract U impulse is delayed a fractio...
Which factors affect blood pressure? 1 the diameter of the blood vessels 2 the systolic pressure of the heart ventricles 3 the volume of blood retu...
The diagram is a summary of the role of haemoglobin in the transport of carbon dioxide. [Figure 30.1] Which set of labels is correct?
The graph shows the oxygen dissociation curves of haemoglobin from two species of mammal, S and T. [Figure 31.1] Which statements could explain the...
Which are present in bronchioles? 1 endothelium 2 ciliated cells 3 smooth muscle tissue
The partial pressure of oxygen in air inside alveoli is 14 kPa. The partial pressure of oxygen in pulmonary capillaries is 6 kPa. What will be the ...
Which can be directly linked to a reduction in the surface area available for gas exchange in human lungs? 1 emphysema 2 lung cancer 3 smoking tobacco
Which row is correct about the affinity between haemoglobin and the gases carbon dioxide, carbon monoxide and oxygen? [Figure 35.1]
An earthquake caused damage to sanitation systems in a large tropical village. Drinking water became contaminated with sewage. Heavy rain then caus...
Which statements about the use of antibiotics could cause an increase in antibiotic-resistant bacteria? 1 Patients do not always complete the cours...
Which row is correct for neutrophils and B-lymphocytes? [Figure 38.1]
Rabies is usually a fatal disease. Rabies is transmitted to people in the saliva of infected animals. A person who has been bitten by an infected a...
Fig. 1.1 is a diagram of a human chromosome at a stage in mitosis. [Figure 1.1]
Fig. 2.1 shows the molecular structure of a triglyceride molecule. [Figure 2.1]
(a) The circulatory system of mammals is a double circulation.
(a) Fig. 4.1 is a scanning electron micrograph of a section of a plant cell wall. In living plant tissue cytoplasmic strands form part of structure...
(a) Fig. 5.1 is a photomicrograph of a section through the lungs showing a bronchus and some alveoli. [Figure 5.1]
(a) Mutations in body cells can sometimes result in a tumour. Some tumours are cancerous.
Fig. 1.1 is a diagram drawn from a photomicrograph of a transverse section through part of a leaf. The arrows in Fig. 1.1 show the movement of wate...
The treatment for people with active tuberculosis (TB) lasts six months and involves a combination of antibiotics. This is usually very effective i...
Fig. 3.1 is a photomicrograph of a section through lung tissue. [Figure 3.1]
In the immune system, a plasma cell develops from an activated B-lymphocyte. Mature plasma cells synthesise and secrete antibody molecules. (a) Fig...
Sucrose phosphorylase is an enzyme found in some species of bacteria. One function of this enzyme is for the production of compounds that help to p...
(a) Fig. 6.1 shows an oxygen dissociation curve for adult human haemoglobin. [Figure 6.1] An increase in the partial pressure of carbon dioxide (pC...
Fig. 1.1 shows a section through the human chest. The gross structure of the human gas exchange system is shown. [Figure 1.1]
The veins of a leaf contain transport tissues. Fig. 2.1 is a drawing made from an electron micrograph showing a cross-section of the transport tiss...
Fig. 3.1 shows the nematode worm, Caenorhabditis elegans. [Figure 3.1] Stem cells of C. elegans have been studied. Fig. 3.2 shows the change in mas...
Antibiotic sensitivity tests can be carried out to choose appropriate antibiotics to use for treatment of bacterial diseases. A researcher carried ...
A molecule of collagen consists of three identical polypeptides that form a triple helix. The amino acid glycine forms one third of the amino acids...
Fig. 6.1 shows Vorticella, which is a single-celled organism that lives in freshwater. Vorticella has many cilia which it uses for feeding. [Figure...
Fig. 2.1 is a photomicrograph of a stained transverse section through a plant root. You are not expected to be familiar with this specimen. [Fig. 2.1]
Fig. 1.1 is a transverse section through a leaf from the maize plant, Zea mays. Maize is a C4 plant. [Figure 1.1]
Domestic goats are small, herbivorous animals that provide milk for human use. Goats' milk is an important source of food for people living in rura...
DNA barcoding is used in species identification. To create a DNA barcode, a specific region of DNA is sequenced so that it can be compared to an on...
There are a number of mutations affecting the production of fetal haemoglobin, HbF, and normal adult haemoglobin, HbA. • The HbA allele codes for t...
Fig. 5.1 shows a cat displaying the recessive phenotype for two unlinked genes. : H/h controls hair length. The allele for short hair is dominant t...
Identify the precise location in a cholinergic synapse that is described in each of the statements. A region that contains many mitochondria. A reg...
(a) Structures and compounds involved in respiration in anaerobic conditions include: A – pyruvate B - reduced NAD C - ethanol D - carbon dioxide E...
Palm oil is a vegetable oil that is used very widely in food products. The oil is extracted from the fruit of the oil palm tree. (a) Oil palm trees...
Section B Answer one question. (a) Describe and explain the properties of plasmids that allow them to be used in gene cloning. [7] (b) Explain the ...
Section B Answer one question. (a) Describe how adrenaline can stimulate liver cells to convert glycogen to glucose. [7] (b) Describe the role of a...
Fig. 1.1 shows a transmission electron micrograph of a chloroplast. [Figure 1.1]
Domestic goats are small, herbivorous animals that provide milk for human use. This is an important source of food for people in rural South Africa...
A subspecies is a genetically distinct population of a species that has some phenotypic differences but is not yet reproductively isolated. 500000 ...
Sickle cell anaemia is a non-infectious chronic disease. If not treated, sickle cell anaemia can be painful and life-threatening. Sickle cell anaem...
Tyrosinase is an enzyme found in mammals. It is involved in the synthesis of melanin pigment. Mutations in the tyrosinase gene affect a mammal's ha...
A person who has a wound to their skin may experience pain. Opioid drugs can be taken to relieve the pain. Opioid receptors are located in the pres...
Insulin is transported around the body in the blood. The cells of the liver, muscle tissue and adipose (fat) tissue have receptors for insulin.
The soft rush plant, Juncus effusus, grows in many habitats in Northern Europe. An investigation was carried out to assess whether there was a rela...