Powerpoint lecture covering the following in a modern, concise format: Specification Point 2.90 - Describe the structure and functioning of a simple reflex arc illustrated by the withdrawal of a finger from a hot object. Specification Point 2.91 - Describe the structure and function of the eye as a receptor. Specification Point 2.92 - Understand the function of the eye in focusing on near and distant objects, and in responding to changes in light intensity. Complete set of Chapter 4 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 2.95B - Understand the sources, roles and effects of the following hormones: ADH, FSH and LH. Complete set of Chapter 4 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 5.5 - Understand the role of yeast in the production of food including bread. Specification Point 5.6 - Practical: investigate the role of anaerobic respiration by yeast in different conditions. Specification Point 5.7 - Understand the role of bacteria (Lactobacillus) in the production of yoghurt. Specification Point 5.8 - Understand the use of an industrial fermenter and explain the need to provide suitable conditions in the fermenter, including aseptic precautions, nutrients, optimum temperature and pH, oxygenation and agitation, for the growth of microorganisms. Complete set of Chapter 7 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: 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 Lectures are available.

Powerpoint lecture 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 Lectures are available.

Complete set of concise, modern presentations for Edexcel IGCSE Chemistry (4CH1) Chapter 6 - Physical Chemistry. Contains colour coded specification points. Five presentations included: 26 - Energetics 27 - Bond Energies 28 - Rates of Reaction 29 - Reversible Reactions 30 - Dynamic Equilibria

Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.6.1.2 - Receptors. Complete set of Chapter 6 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 4.5.1 - Homeostasis. Specification Point 4.5.2.4 - Control of body temperature. Complete set of Chapter 5 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 4.5.3.3 - Maintaining water and nitrogen balance in the body. Complete set of Chapter 5 Lectures are available.

Complete set of concise, modern presentations for Edexcel IGCSE Chemistry (4CH1) Chapter 3 - Bonding. Contains colour coded specification points. Four presentations included: 12 - Ionic Bonding 13 - Covalent Bonding 14 - Metallic Bonding 15 - Electrolysis

Powerpoint lecture 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 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 4.7.1.4 - Adaptations. Specification Point 4.7.2.1 - Levels of organisation. Practical 9 - Measuring the population size of a common species in a habitat. Using sampling techniques to investigate the effect of a factor on the distribution of this species. Complete set of Chapter 7 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 8.2 - Understand the positive and negative impacts of the growth of global tourism, including mass tourism, on the environment, economy and people of destination areas. Complete set of Chapter 9 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 7.3 - Understand how technology can resolve water-resource shortages in fragile environments under threat from desertification. Specification Point 7.3 - Understand the different approaches to the sustainable use and management of a rainforest in a named region to limit the extent of deforestation. Complete set of Chapter 8 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 7.3 - Understand different responses to global warming and climate change from individuals, organisations and governments in a named developed and a named emerging or developing country. Complete set of Chapter 8 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 8.1 - Understand the push and pull factors that have influenced rates of different types of migration over the last 50 years. Complete set of Chapter 9 Lectures are available.

Companion PDF worksheet for Edexcel IGCSE Biology Lecture 33 - Controlling Body Temperature. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 2.93 - Describe the role of the skin in temperature regulation, with reference to sweating, vasoconstriction and vasodilation. Complete set of Chapter 4 Worksheets are available.

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 2.94 - Understand the sources, roles and effects of the following hormones: adrenaline, insulin, testosterone, progesterone and oestrogen. Complete set of Chapter 4 Lessons are available.

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 2.93 - Describe the role of the skin in temperature regulation, with reference to sweating, vasoconstriction and vasodilation. Complete set of Chapter 4 Lessons are available.

Complete set of PDF worksheets for Edexcel IGCSE Biology (4BI0) Chapter 3 - Movement of Substances in Living Organisms. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. All questions are original. Nine worksheets included: 18 - Gas Exchange in Plants 19 - Ventilation 20 - The Alveoli and Lung Disease 21 - Transport Mechanisms 22 - Transpiration 23 - The Blood 24 - Vaccination 25 - The Heart 26 - The Circulatory System