Cambridge Past Paper Questions
Browse 23,045questions from 25 years of O-Level & A-Level exams. Click any question to practice.
Mitochondria are thought to have evolved from prokaryotic cells that were ingested by an ancestral cell. Which feature have these prokaryotes lost ...
A student carried out the Benedict's test on a sample and got a negative result. What should the student do to confirm there are no sugars present ...
The diagrams show three hexoses. [Figure 8.1] In which carbohydrates do these three hexoses occur? [Figure 8.2]
The diagram shows part of the chemical structure of a naturally occurring polysaccharide. [Figure 9.1] What types of glycosidic bonds are present?
What is the maximum number of water molecules produced when a triglyceride is synthesised?
What occurs during the formation of a peptide bond between two amino acids?
The diagram represents roles of water in living organisms. [Figure 12.1] Which roles are dependent upon hydrogen bonds between water molecules?
The diagram shows a metabolic pathway. [Figure 13.1] What would be the effect of adding a small amount of a non-competitive inhibitor of enzyme 2?
Two enzymes are added to a solution containing a low concentration of a substrate that they can both use. Which statement is correct?
The diagram shows the fluid mosaic model of membrane structure. Structures 1, 2, 3 and 4 are types of molecule. [Figure 15.1] Which types of molecu...
What is the role of G protein in cell signalling?
When a small quantity of phospholipid is added to a test-tube of water and then shaken vigorously, an emulsion is formed by small droplets called l...
What are the features of facilitated diffusion? 1 It uses protein channels in the membrane and is driven by the energy from ATP. 2 It moves molecul...
Which description of chromosome structure is correct?
Which processes involve mitosis? [Figure 20.1]
A drug has been developed to treat certain types of cancer. It prevents mitosis by binding to the spindle and preventing sister chromatids being se...
Some viruses have single-stranded DNA as their genetic material. This DNA molecule has to be folded to fit in the protein coat. Which statements ab...
How many statements are true for semi-conservative replication of DNA in a eukaryotic cell? 1 The process takes place in the nucleus. 2 Adenine wil...
Part of the nucleotide sequence of an mRNA molecule is shown, with spaces between the codons. CAG UAC AGC AAU CUA UAA The translation of the codons...
External factors change the rate of transpiration, which also affects the water potential gradient of cells in the leaf. Which combination is corre...
The photomicrograph shows a transverse section through a leaf. [Figure 26.1] Which features of a xerophytic leaf are visible in this section? 1 sun...
Which changes occur as carbohydrates move out of a root cell into a phloem sieve tube? [Figure 27.1]
The photomicrograph shows three white blood cells labelled X, Y and Z. [Figure 28.1] Which row correctly identifies these cells? [Figure 28.2]
The graph represents data on blood vessels and blood flow. [Figure 29.1] Which row correctly identifies the curves? [Figure 29.2]
Which components of blood are present in lymph? [Figure 30.1]
What correctly describes the significance of the increase of the red blood cell count of humans who move from living at low altitude to high altitude?
Which structures of the human gas exchange system are supported by cartilage? [Figure 32.1]
Carbon monoxide, nicotine and tar are components of tobacco smoke. Which row correctly describes their effect on a smoker's body? [Figure 33.1]
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...