Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.2.4 - Cell recognition and the immune system. Complete set of Chapter 2 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 1.1 - Understand the features of a drainage basin: source, watershed, channel network and mouth. Complete set of Chapter 1 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 5.2 - Understand characteristics of a rural environment: landscape, climate, settlement, population, land use, employment, accessibility, management (development or conservation). Complete set of Chapter 6 Lectures are available.

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 2.28 - Describe the use of litmus, phenolphthalein and methyl orange to distinguish between acidic and alkaline solutions. Specification Point 2.29 - Understand how the pH scale can be used to classify solutions as strongly acidic, weakly acidic, neutral, weakly alkaline and strongly alkaline. Specification Point 2.30 - Describe the use of universal indicator to measure the approximate pH value of an aqueous solution. Specification Point 2.31 - Know that acids in aqueous solution are a source of hydrogen ions and alkalis in a aqueous solution are a source of hydroxide ions. Specification Point 2.32 - Know that alkalis can neutralise acids. Complete set of Chapter 5 Lessons are available.

Companion PDF worksheet for Edexcel IGCSE Chemistry Lecture 11 - Concentrations and Volumes. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 1.34C - Understand how to carry out calculations involving amount of substance, volume and concentration of solution. Specification Point 1.35C - Understand how to carry out calculations involving gas volumes and the molar volume of a gas. Complete set of Chapter 2 Worksheets are available.

Companion PDF worksheet for Edexcel IGCSE Chemistry Lecture 10 - Formulae and Calculations Part 2. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 1.29 - Calculate reacting masses using experimental data and chemical equations. Specification Point 1.30 - Calculate percentage yield. Specification Point 1.31 - Understand how the formulae of simple compounds can be obtained experimentally, including metal oxides, water and salts containing water of crystallisation. Specification Point 1.32 - Know what is meant by the terms empirical formula and molecular formula. Specification Point 1.33 - Calculate empirical and molecular formulae from experimental data. Complete set of Chapter 2 Worksheets are available.

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 1.37 - Understand how ions are formed by electron loss or gain. Specification Point 1.38 - Know the charges of several atomic and molecular ions. Specification Point 1.39 - Write formulae for compounds formed between the ions listed in 1.38. Specification Point 1.40 - Draw dot-and-cross diagrams to show the formation of ionic compounds by electron transfer, limited to combinations of elements from groups 1, 2, 3, 5, 6 and 7. Specification Point 1.41 - Understand ionic bonding in terms of electrostatic attractions. Specification Point 1.42 - Understand why compounds with giant ionic lattices have high melting and boiling points. Specification Point 1.43 - Know that ionic compounds do not conduct electricity when solid, but do conduct electricity when molten and in aqueous solution. Complete set of Chapter 3 Lessons are available.

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 2.44 - Describe tests for these gases: hydrogen, oxygen, carbon dioxide, ammonia and chlorine. Specification Point 2.45 - Describe how to carry out a flame test. Specification Point 2.46 - Know the colours formed in flame tests for the following cations: lithium, sodium, potassium, calcium and copper. Specification Point 2.47 - Describe tests for these cations: ammonium using sodium hydroxide solution and identifying the gas evolved. Copper, iron (II) and iron (III) using sodium hydroxide solution. Specification Point 2.48 - Describe tests for these anions: chloride, bromide and iodide using acidified silver nitrate solution. Sulphates using acidified barium chloride solution and carbonates using hydrochloric acid and identifying the gas evolved. Specification Point 2.49 - Describe a test for the presence of water using anhydrous copper (II) sulphate. Specification Point 2.50 - Describe a physical test to show whether a sample of water is pure. Complete set of Chapter 5 Lessons are available.

Complete set of companion PDF worksheets for Edexcel IGCSE Chemistry (4CH1) Chapter 5 - Acids, Bases and Salts. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Five worksheets included: 21 - Acids and Alkalis 22 - Titrations 23 - Acids, Bases and Salts 24 - Making Salts 25 - Chemical Tests

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 3.9 - Describe experiments to investigate the effects of changes in surface area of a solid, concentration of a solution, temperature and the use of a catalyst on the rate of a reaction. Specification Point 3.10 - Describe the effects of changes in surface area of a solid, concentration of a solution, pressure of a gas, temperature and the use of a catalyst on the rate of a reaction. Specification Point 3.11 - Explain the effects of changes in surface area of a solid, concentration of a solution, pressure of a gas and temperature on the rate of a reaction in terms of particle collision theory. Specification Point 3.12 - Know that a catalyst is a substance that increases the rate of a reaction, but is chemically unchanged at the end of the reaction. Specification Point 3.13 - Know that a catalyst works by providing an alternative pathway with lower activation energy. Specification Point 3.15 - Practical: investigate the effect of changing the surface area of marble chips and of changing the concentration of hydrochloric acid on the rate of reaction between marble chips and dilute hydrochloric acid. Specification Point 3.16 - Practical: investigate the effect of different solids on the catalytic decomposition of hydrogen peroxide solution. Complete set of Chapter 6 Lessons are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.8.1 - Alteration of the sequence of bases in DNA can alter the structure of proteins. Specification Point 3.8.2.3 - Gene expression and cancer. Complete set of Chapter 8 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.8.3 - Using genome projects. Specification Point 3.8.4.1 - Recombinant DNA technology. Complete set of Chapter 8 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 1.10 Describe the following experimental techniques for the separation of mixtures: Simple distillation. Fractional distillation. Filtration. Crystallisation. Paper chromatography. Complete set of Chapter 1 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 5.17B - Describe the process of micropropagation (tissue culture) in which explants are grown in vitro. Specification Point 5.18B - Understand how micropropagation can be used to produce commercial quantities of genetically identical plants with desirable characteristics. Specification Point 5.19B - Describe the stages in the production of cloned mammals involving the introduction of a diploid nucleus from a mature cell into an enucleated egg cell, illustrated by Dolly the sheep. Complete set of Chapter 7 Lectures are available.

Complete set of concise, modern presentations for Edexcel IGCSE Biology (4BI0) Chapter 4 - Coordination and Control. Contains colour coded specification points with handmade vector graphics. Nine presentations included: 27 - Excretion 28 - The Kidneys 29 - Coordination 30 - Coordination in Plants 31 - Coordination in Humans 32 - Reflexes and the Eye 33 - Controlling Body Temperature 34 - Hormones 35 - More Hormones

Powerpoint lecture covering the following in a modern, concise format: Specification Point 1.55C - Understand why covalent compounds do not conduct electricity. Specification Point 1.56C - Understand why ionic compounds conduct electricity only when molten or in aqueous solution. Specification Point 1.57C - Know that anion and cation are terms used to refer to negative and positive ions respectively. Specification Point 1.58C - Describe experiments to investigate electrolysis, using inert electrodes, of molten compounds and aqueous solutions and to predict the products. Specification Point 1.59C - Write ionic half-equations representing the reactions at the electrodes during electrolysis and understand why these reactions are classified as oxidation or reduction. Specification Point 1.60C - Practical: investigate the electrolysis of aqueous solutions. Complete set of Chapter 3 Lectures are available.

Complete set of concise, modern presentations for Edexcel IGCSE Chemistry (4CH1) Chapter 5 - Acids, Bases and Salts. Contains colour coded specification points. Five presentations included: 21 - Acids and Alkalis 22 - Titrations 23 - Acids, Bases and Salts 24 - Making Salts 25 - Chemical Tests

Powerpoint lecture covering the following in a modern, concise format: Specification Point 8.2 - Understand the impacts of globalisation on different groups of people, including the benefits and costs to countries hosting TNCs. Specification Point 8.2 - Understand the impacts of migration (voluntary, forced, national, international and rural-urban) on different groups of people. Complete set of Chapter 9 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 2.40B - Understand the role of diffusion in gas exchange. Specification Point 2.41B - Understand gas exchange in relation to respiration and photosynthesis. Specification Point 2.42B - Understand how the structure of the leaf is adapted for gas exchange. Specification Point 2.43B - Describe the role of stomata in gas exchange. Complete set of Chapter 3 Lectures are available.

Companion PDF worksheet for Edexcel IGCSE Biology Lecture 18 - Gas Exchange in Plants. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 2.40B - Understand the role of diffusion in gas exchange. Specification Point 2.41B - Understand gas exchange in relation to respiration and photosynthesis. Specification Point 2.42B - Understand how the structure of the leaf is adapted for gas exchange. Specification Point 2.43B - Describe the role of stomata in gas exchange. Complete set of Chapter 3 Worksheets are available.