Cambridge & Pearson Edexcel Past Paper Questions

Visking tubing can be used to investigate the properties of cell membranes. A student carried out an experiment to investigate osmosis using Viskin...

The induced-fit hypothesis and the lock-and-key hypothesis are used to describe the mode of action of enzymes. Radish plants contain the enzyme per...

Much success was made in reducing the number of cases of malaria between 2000 and 2015.

Lysosomes are cell structures that contain enzymes known as acid hydrolases. Fig. 6.1 shows some processes that occur in animal cells. [Figure 6.1]

(a) Fig. 1.1 is a photomicrograph of a region of eukaryotic tissue. Some of the cells are in stages of mitosis. E F Fig. 1.1

Sugars are transported within phloem sieve tubes from a source, such as a mature leaf, to a young leaf, which acts as a sink. The young leaf also n...

In mammals, some cell signalling molecules are steroid (lipid) hormones. These hormones are transported in the bloodstream to reach capillary netwo...

A person who is exposed to tobacco smoke is at greater risk of lung cancer and chronic obstructive pulmonary disease (COPD). Many people with COPD...

Fig. 5.1 is a transmission electron micrograph showing parts of two plant cells. The function of the middle lamella is cell-to-cell adhesion. The m...

The diseases myasthenia gravis (MG) and HIV/AIDS both involve disorders of the immune system.

The Golgi body, rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER) form part of the internal membrane system of a cell. The m...

Smallpox, measles and HIV/AIDS are infectious diseases caused by different viruses. These different viruses share some structural features.

HIV protease is an enzyme composed of two identical polypeptide chains. Each polypeptide chain is 99 amino acids long. During translation, the amin...

Phloem sap is transported within phloem sieve tubes.

Fig. 5.1 shows four types of cell that can be seen in a prepared slide of blood taken from a mammal. [Figure 5.1]

The best time to obtain a clear image of chromosomes during a mitotic cell cycle is during the metaphase stage. Fig. 6.1 is a scanning electron mic...

J1 is a slide of a stained transverse section through a plant leaf.

Some biological molecules produce a colour change when tested with a specific reagent. You will investigate which biological molecules are present ...

L1 is a slide of a stained transverse section through a plant leaf. (a) Set up the microscope so that you can observe the section on L1. Use a shar...

Photosynthesis is a complex process involving the transfer of light energy into chemical energy. The rate of photosynthesis is affected by many env...

All organisms respire to release energy from energy-rich molecules such as glucose. Some factory workers in the early 20th century were exposed to ...

In 2014, scientists published a phylogenetic (evolutionary) tree diagram showing how and when different groups of insects developed from ancestral ...

Genetic engineering involves the manipulation of naturally occurring enzymes and processes. Genetically modified organisms (GMOs) include crop plan...

Nerves consist of bundles of different types of neurones. Fig. 5.1 shows the mean transmission speed of impulses for three types of sensory neurone...

Thermoregulation is the control of the core temperature of the body. Thermoreceptors send information about a change in core temperature to the hyp...

People vary in which molecules are present on the surface of their red blood cells. For example, in the ABO blood group system, people may be categ...

Humans use selective breeding to improve the features of crop plants and domestic animals.

Describe how you would carry out an investigation to calculate the effect of substrate concentration on the rate of respiration of yeast in anaerob...

Explain how speciation can occur due to geographical separation.

(a) Fig. 1.1 is a diagram of part of a neurone membrane at resting potential. [Figure 1.1]

(a) All organisms respire. The ATP produced as a result of respiration is used as the energy currency of the cell. (b) Fur seals are mammals that ...

(a) One way to measure global biodiversity is to count the number of species of organisms. Table 3.1 shows estimates for 2009 of the number of spe...

(a) Genetic technology involving the creation of recombinant DNA can be used to treat different human diseases. These include diseases such as diab...

(a) Photosynthesis is a complex process involving a light dependent stage and a light independent stage. A student carried out an experiment to in...

Glucagon-like peptide-1 (GLP-1) is a hormone consisting of 31 amino acids. It is secreted by specialised intestinal epithelial cells known as L cel...

(a) The fruit fly, Drosophila melanogaster, feeds on sugars found in damaged fruits. A fruit fly with normal features is described as wild type. I...

(a) In continuous variation, a population shows a range of phenotypes between two extremes with no distinct groups. Height and mass are examples of...

(a) Describe how the structure of a mitochondrion is related to its function. (b) Explain how rice is adapted to grow with its roots submerged in ...

(a) Explain how different types of gene mutation can affect the phenotype and outline the effects of the mutant alleles that cause Huntington's dis...

Fig. 1.1 is a diagram of a part of a sarcomere in striated muscle. [Figure 1.1]

Cells can maintain a different concentration of ions within the cell compared with the extracellular environment. It is estimated that animals may ...

Fruit flies of the genus Bactrocera are pests that damage fruit crops. Table 3.1 gives the names and geographical ranges of Bactrocera fruit flies ...

Bt maize has been genetically engineered to resist insect attack. In 2019, Bt maize formed 83% of the maize grown in the USA. Outline how the genet...

Photosynthesis is a process that results in the synthesis of complex organic molecules. Respiration is a process that involves the breakdown of com...

(a) The bottlenose dolphin, Tursiops truncatus, is an aquatic mammal. It has adaptations to conserve heat when swimming in cold water. Fig. 6.1 sho...

(a) Haemoglobin is made of two α-globin chains and two β-globin chains. A person may have a mutation in the gene coding for β-globin. This is due t...

Explain what is meant by stabilising selection.

The enzyme ẞ-galactosidase catalyses the breakdown of the compound ONPG (o-nitrophenyl 1-D-galactopyranoside) to the compound ONP (o-nitrophenyl), ...

Inheritance of flower colour and flower position in pea plants are controlled by two genes. • Gene P/p controls flower colour. Allele P for purple...

The enzyme catalase catalyses the reaction shown in Fig. 1.1. catalase hydrogen peroxide → water + oxygen [Figure 1.1] A student had read that co...