Powerpoint lecture covering the following in a modern, concise format: Specification Point 4.3B - Understand the term biodiversity. Specification Point 4.4B - Practical: investigate the distribution of organisms in their habitats and measure biodiversity using quadrats. Complete set of Chapter 6 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 2.5 - Know the colours, physical states (at room temperature) and trends in physical properties of chlorine, bromine and iodine. Specification Point 2.6 - Use knowledge of trends in group 7 to predict the properties of other halogens. Specification Point 2.7 - Understand how displacement reactions involving halogens and halides provide evidence for the trend in reactivity in group 7. Specification Point 2.8C - Explain the trend in reactivity in group 7 in terms of electronic configurations. Complete set of Chapter 4 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 1.1 - Understand how to use some common units in physics. Specification Point 1.3 - Plot and explain distance−time graphs. Specification Point 1.4 - Know and use the relationship between average speed, distance moved and time taken. Specification Point 1.5 - Practical: investigate the motion of everyday objects such as toy cars or tennis balls. Complete set of Chapter 1 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 9.1 - Understand the different ways of defining development, using economic criteria and broader social and political measures. Complete set of Chapter 10 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.4.2 - DNA and protein synthesis. Complete set of Chapter 4 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.3.1 - Surface area to volume ratio. Complete set of Chapter 3 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 2.24 - Understand that a balanced diet should include appropriate proportions of carbohydrate, protein, lipid, vitamins, minerals, water and dietary fibre. Specification Point 2.25 - Identify the sources and describe the functions of carbohydrate, protein, lipid (fats and oils), vitamins A, C and D, the mineral ions calcium and iron, water and dietary fibre as components of the diet. Specification Point 2.26 - Understand how energy requirements vary with activity levels, age and pregnancy. Complete set of Chapter 2 Lectures are available.

PowerPoint lecture covering the following in a modern, concise format: Specification Point 4.1.1.1 - Energy stores and systems. Complete set of Chapter 1 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 8.3 - Understand how geopolitical relationships between countries are important in managing trade, migration and tourism. Complete set of Chapter 9 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 1.44 - Know that a covalent bond is formed between atoms by the sharing of a pair of electrons. Specification Point 1.45 - Understand covalent bonds in terms of electrostatic attractions. Specification Point 1.46 - Understand how to use dot-and-cross diagrams to represent covalent bonds in a variety of molecules. Specification Point 1.47 - Explain why substances with a simple molecular structures are gases or liquids, or solids with low melting and boiling points. Specification Point 1.48 - Explain why the melting and boiling points of substances with simple molecular structures increase, in general, with increasing relative molecular mass. Specification Point 1.49 - Explain why substances with giant covalent structures are solids with high melting and boiling points. Specification Point 1.50 - Explain how the structures of diamond, graphite and fullerene influence their physical properties, including electrical conductivity and hardness. Specification Point 1.51 - Know that covalent compounds do not usually conduct electricity. Complete set of Chapter 3 Lectures are available.

Companion PDF worksheet for Edexcel IGCSE Chemistry Lecture 26 - Energetics. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 3.1 - Know that chemical reactions in which heat energy is given out are described as exothermic, and those in which heat energy is taken in are described as endothermic. Specification Point 3.2 - Describe simple calorimetry experiments for reactions such as combustion, displacement, dissolving and neutralisation. Specification Point 3.3 - Calculate the heat energy change from a measured temperature change using the expression Q = mcΔT. Specification Point 3.4 - Calculate the molar enthalpy change (ΔH) from the heat energy change, Q. Specification Point 3.8 - Practical: investigate temperature changes accompanying some of the following types of change: salts dissolving in water, neutralisation reactions, displacement reactions and combustion reactions. Complete set of Chapter 6 Worksheets are available.

Companion PDF worksheet for Edexcel IGCSE Physics Lecture 30 - Fission and Fusion. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 7.17 - Know that nuclear reactions, including fission, fusion and radioactive decay, can be a source of energy. Specification Point 7.18 - Understand how a nucleus of U-235 can be split by collision with a neutron, and that this process releases energy as kinetic energy of the fission products. Specification Point 7.19 -Know that the fission of U-235 produces two radioactive daughter nuclei and a small number of neutrons. Specification Point 7.20 - Describe how a chain reaction can be set up if the neutrons produced by one fission strike other U-235 nuclei. Specification Point 7.21 - Describe the role played by the control rods and moderator in the fission process. Specification Point 7.22 - Understand the role of shielding around a nuclear reactor. Specification Point 7.23 - Explain the difference between nuclear fusion and nuclear fission. Specification Point 7.24 - Describe nuclear fusion as the creation of larger nuclei resulting in a loss of mass from smaller nuclei, accompanied by a release of energy. Specification Point 7.25 - Know that fusion is the energy source for stars. Specification Point 7.26 - Explain why nuclear fusion does not happen at low temperatures and pressures, due to electrostatic repulsion of protons. Complete set of Chapter 7 Worksheets are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 1.3 - Understand case studies of river management in a developed country and a developing or emerging country. Complete set of Chapter 1 Lectures are available.

Companion PDF worksheet for Edexcel IGCSE Physics Lecture 31 - The Universe. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 8.2 - Know that the universe is a large collection of billions of galaxies, that a galaxy is a large collection of billions of stars and that our solar system is in the Milky Way galaxy. Specification Point 8.3 - Understand why gravitational field strength, g, varies and know that it is different on other planets and the Moon from that on the Earth. Specification Point 8.4 - Explain that gravitational force causes moons to orbit planets, causes the planets to orbit the Sun, causes artificial satellites to orbit the Earth and causes comets to orbit the Sun. Specification Point 8.5 - Describe the differences in the orbits of comets, moons and planets. Specification Point 8.6 - Use the relationship between orbital speed, orbital radius and time period. Complete set of Chapter 8 Worksheets are available.

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 7.17 - Know that nuclear reactions, including fission, fusion and radioactive decay, can be a source of energy. Specification Point 7.18 - Understand how a nucleus of U-235 can be split by collision with a neutron, and that this process releases energy as kinetic energy of the fission products. Specification Point 7.19 -Know that the fission of U-235 produces two radioactive daughter nuclei and a small number of neutrons. Specification Point 7.20 - Describe how a chain reaction can be set up if the neutrons produced by one fission strike other U-235 nuclei. Specification Point 7.21 - Describe the role played by the control rods and moderator in the fission process. Specification Point 7.22 - Understand the role of shielding around a nuclear reactor. Specification Point 7.23 - Explain the difference between nuclear fusion and nuclear fission. Specification Point 7.24 - Describe nuclear fusion as the creation of larger nuclei resulting in a loss of mass from smaller nuclei, accompanied by a release of energy. Specification Point 7.25 - Know that fusion is the energy source for stars. Specification Point 7.26 - Explain why nuclear fusion does not happen at low temperatures and pressures, due to electrostatic repulsion of protons. Complete set of Chapter 7 Lessons are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.1.1.3 - Electron configuration. Complete set of Chapter 1 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 2.34 - Understand how the process of respiration produces ATP in living organisms. Specification Point 2.35 - Know that ATP provides energy for cells. Specification Point 2.36 - Describe the differences between aerobic and anaerobic respiration. Specification Point 2.37 - Know the word equation and the balanced chemical symbol equation for aerobic respiration in living organisms. Specification Point 2.38 - Know the word equation for anaerobic respiration in plants and in animals. Specification Point 2.39 - Practical: investigate the evolution of carbon dioxide and heat from respiring seeds or other suitable living organisms. Complete set of Chapter 2 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 2.86 - Describe how nervous and hormonal communication control responses and understand the differences between the two systems. Specification Point 2.87 - Understand that the central nervous system consists of the brain and spinal cord and is linked to sense organs by nerves. Specification Point 2.88 - Understand that stimulation of receptors in the sense organs sends electrical impulses along nerves into and out of the central nervous system, resulting in rapid responses. Specification Point 2.89 - Understand the role of neurotransmitters at synapses. Complete set of Chapter 4 Lectures are available.

Powerpoint lecture and associated PDF worksheet covering the following in a modern, concise format: Specification Point 8.2 - Know that the universe is a large collection of billions of galaxies, that a galaxy is a large collection of billions of stars and that our solar system is in the Milky Way galaxy. Specification Point 8.3 - Understand why gravitational field strength, g, varies and know that it is different on other planets and the Moon from that on the Earth. Specification Point 8.4 - Explain that gravitational force causes moons to orbit planets, causes the planets to orbit the Sun, causes artificial satellites to orbit the Earth and causes comets to orbit the Sun. Specification Point 8.5 - Describe the differences in the orbits of comets, moons and planets. Specification Point 8.6 - Use the relationship between orbital speed, orbital radius and time period. Complete set of Chapter 8 Lessons are available.

Companion PDF worksheet for Edexcel IGCSE Physics Lecture 25 - Magnetism. Contains short answer questions, an activity requiring lateral thinking and exam-style questions. Specification Point 6.1 - Use the following units: ampere (A), volt (V) and watt (W). Specification Point 6.2 - Know that magnets repel and attract other magnets and attract magnetic substances. Specification Point 6.3 - Describe the properties of magnetically hard and soft materials. Specification Point 6.4 - Understand the term magnetic field line. Specification Point 6.5 - Know that magnetism is induced in some materials when they are placed in a magnetic field. Specification Point 6.6 - Practical: investigate the magnetic field pattern for a permanent bar magnet and between two bar magnets. Specification Point 6.7 - Describe how to use two permanent magnets to produce a uniform magnetic field pattern. Complete set of Chapter 6 Worksheets are available.