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.
Some stains can be used to identify cell structures in living cells. A dilute solution of one stain causes the whole cell to appear blue. The blue ...
When mucus is secreted from a goblet cell, these events take place. 1 addition of carbohydrate to protein 2 fusion of a vesicle with the cell surfa...
The diagram shows four biological features. 4 RNA, 1 DNA, 3 70S ribosomes, 2 capsid. Which biological features are present in typical prokaryotes? ...
Which row shows features that occur in dicotyledonous plant cells and also in typical bacterial cells? key ✓ = found in dicotyledonous plant cells ...
Which flow chart outlining the test for non-reducing sugars is correct? [Figure 7.1]
Which diagrams show the release of a water molecule during the formation of a glycosidic bond? [Figure 8.1]
Which molecules have a structural formula that contains C=O bonds? 1 amino acids 2 fatty acids 3 glycerol 4 protein
Which statement about triglycerides is correct?
Many flowers produce a sweet solution called nectar. Bees provided with nectar use enzyme Q to change the nectar into honey. After testing a sample...
The diagram shows the structure of part of a peptidoglycan molecule. [Figure 12.1]
A scientist investigated the progress of two enzyme-catalysed reactions in separate test-tubes, X and Y. Both reactions result in colour changes th...
A student investigated the hydrolysis of lipid in high-fat milk, using the enzyme lipase. • 1 cm³ of enzyme solution was added to 10 cm³ of high-fa...
Where in the cell surface membrane are the carbohydrate chains of glycoproteins and glycolipids mainly located?
Sodium ions can enter cells across the cell surface membrane. Which methods could be used by sodium ions to cross a cell surface membrane and enter...
The diagram shows how an artificial partially permeable membrane was used to separate a 5% sodium chloride solution and a 10% sodium chloride solut...
Agar cubes can be used to demonstrate the effect on diffusion of changing the surface area to volume ratio. Three different agar cubes made using a...
During sperm formation in mammals, part of the structure of each chromosome is replaced with proteins called protamines. This replacement allows th...
The diagram shows the mitotic cell cycle. During which phase do chromosomes condense and become visible? [Figure 21.1]
Which statements correctly describe features of stem cells that are essential for their role in cell replacement and tissue repair? 1 After mitosis...
Which statements are correct for all nucleotides? 1 The nitrogen-containing base is always attached to carbon atom 1 of the pentose. 2 The phosphat...
How many phosphodiester bonds are present in a circular DNA molecule of 2700 base pairs?
Which statements about complementary base pairing are correct? 1 Purines and pyrimidines are different sizes. 2 Complementary base pairing occurs d...
During the mitotic cell cycle, the chromosomal DNA is replicated. The specific points in DNA molecules where replication is occurring are known as ...
Which molecule has its synthesis directly controlled by DNA?
Which statement correctly describes the association between a companion cell and its sieve tube cell?
A maize seedling was grown in soil that contained lanthanum ions labelled with a chemical that fluoresces under ultraviolet light. The diagram repr...
Which description of adhesion and cohesion is correct?
Which conditions are needed to allow the mass flow of sucrose in phloem sieve tubes?
One type of congenital heart defect is where the left and right atria are not completely separated. This is called an atrial septal defect (ASD). A...
Which property of water, related to its role in blood and tissue fluid, is correctly described?
Which statement about tissue fluid formation is correct?
Oxyhaemoglobin, carbaminohaemoglobin, haemoglobinic acid and carbonic anhydrase are found inside red blood cells. How many of these substances will...
Which of these structures typically contain cartilage and cilia? 1 bronchi 2 bronchioles 3 trachea
Which statements about the function of tissues found in the human gas exchange system are correct? 1 Collagen in the bronchi prevents them collapsi...
Antibiotic-resistant strains of Mycobacterium tuberculosis are a major problem when treating TB. A new antibiotic, teixobactin, could be very effec...
Monoclonal antibodies are now being used to treat some human diseases. What explains why monoclonal antibodies are suitable for this purpose? 1 The...
Measles is an infectious disease caused by a virus. The graph shows the number of cases of measles each year in a country before and after a vaccin...
Fig. 1.1 is a diagram representing part of the phospholipid bilayer of a cell surface membrane. [Figure 1.1] Identify the part of a phospholipid mo...
Table 2.1 shows descriptions of three types of white blood cell. Complete Table 2.1 by stating the names of these three types of white blood cell. ...
Fig. 3.1 is a photomicrograph showing part of a transverse section through the root of an iris, Iris germanica. Irises are herbaceous monocotyledon...
Table 4.1 shows a sequence of 12 nucleotides in the template strand of a short length of a DNA molecule, the corresponding primary transcript and t...
The pathogen that causes cholera is a prokaryote.
Fig. 6.1 is a simplified diagram representing a section through the human immunodeficiency virus (HIV) particle that causes HIV/AIDS. The diagram s...
Seeds of many plant species contain an enzyme that is used to hydrolyse sucrose into reducing sugars. This enzyme is essential to provide the reduc...
P1 is a slide of a stained transverse section through a plant leaf. (b) Fig. 2.1 is a photomicrograph of a transverse section through a leaf of a d...
Fig. 1.1 is a diagram of a nephron. [Figure 1.1]
The scientist Gregor Mendel investigated differences in the length of the stem in the pea plant, Pisum sativum. In 1866, he published the results o...
Cystic fibrosis is an autosomal recessive genetic disease. People with cystic fibrosis have a homozygous recessive genotype.
Holstein Friesian cattle are a breed of cattle used by dairy farmers in many countries of the world for the high milk yield of their cows. [Figure ...
Complete the following paragraphs using the most appropriate word or words. The theory of evolution describes a process that can lead to the format...