Several different treatments are used to autolyse yeast cells. The viability of the autolysed yeast is then tested by: plating out on agar; testing for dehydrogenase activity; microscopic examination with methylene blue.

In this activity, students investigate the three main types of memory - sensory, short-term and long-term. An explanation is given for each one and linked to a memory experiment. Students are also given five memory tasks to complete which include looking at factors that affect peoples' memories and ways in which to...

A Year Ten module from the Salters’ double award science course. The first section of the module introduces the formation, composition and structure of the atmosphere. The Sun is our main source of energy. Students consider why sunlight is more intense near the equator...

This chemistry extension module for the Salters’ Science course deals with the nutrients provided by food and their contribution to the diet. It also deals with methods of food processing and preservation. The module begins with a survey of the chemical composition and...

A Year 11 module from the Salters’ Key Stage Four double award science course. This module begins with revision of prior knowledge about stars, planets, moons and other bodies found in space. Students then consider gravity as the force which controls movement of bodies...

Details of this challenging experiment were published in this leaflet from the Unilever Laboratory Experiment in 1965. Requirements included a pyrophoric nickel catalyst supplied by Unilever, hydrogen from a cylinder and a vegetable oil treated with activated charcoal to remove impurities. The necessary apparatus...

The work suggested in this Nuffield Working with Science unit was planned so that students should:
1. be aware of the advantages of a systematic approach to car selection and purchase
2. be aware of the legal and social responsibilities of car ownership
3...

In this biology extension module of the Salters’ Science course, an exhibition of foods is used to introduce examples of using microbes in food processing. Students make sauerkraut and learn about the establishment of microbial populations in new habitats. Positive uses...

This Unilever Laboratory Experiment describes the preparation of soap from a mixture of cooking oil and dripping. The leaflet was first published in 1964 and so lacks modern safety guidance. The procedure is authentic; it is designed to produce a convincing sample of soap. This means that it could be the basis of...

The method of preparation of a sulphonate paste described in this Unilever Laboratory Experiment is basically the same as that used by Unilever in the large-scale production of soapless detergents at the time of publication in 1964. The required reactants included an alkylbenzene hydrocarbon supplied by the...

This Unilever Laboratory Experiment, published in 1969, gives the procedure for using corrosion (ferroxyl) indicator to demonstrate anodic and cathodic areas on the surface of steel as it corrodes.

In this practical protocol students investigate one way in which bacteria acquire antibiotic resistance through conjugation - horizontal gene transfer from one bacterial strain or species to another.

Plasmid-mediated evolution is fast because whole functional ‘modules’ are lost and gained, rather than the...

Children are challenged by the ‘Bubbles Company’ to find the best bubble mixture. They experiment with washing-up liquid and water to find the bubble which lasts the longest. They use trial and error to find a recipe which is just right. This activity suits outdoor learning but can be done inside too.

RAL Space is the UK’s national space laboratory where our thermal engineers and technicians help design and build spacecraft. They make sure that the components will work correctly and are protected in the extreme temperatures of space by using a special type of insulation. In this activity and presentation, pupils...

This Unilever Laboratory Experiment, published in 1970, describes the analysis of fluorescers from soap and soapless detergent powders. The procedure describes how the fluorescers can be extracted from the product, separated by thin layer chromatography techniques, and made visible by exposing the chromatograms to...