Powerpoint lecture covering the following in a modern, concise format: Specification Point 4.11B - Describe the stages in the nitrogen cycle, including the roles of nitrogen fixing bacteria, decomposers, nitrifying bacteria and denitrifying bacteria. Complete set of Chapter 6 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 4.10 - Describe the stages in the carbon cycle, including respiration, photosynthesis, decomposition and combustion. Complete set of Chapter 6 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.35B - Understand how a change in DNA can affect the phenotype by altering the sequence of amino acids in a protein. Specification Point 3.36B - Understand how most genetic mutations have no effect on the phenotype, some have a small effect and rarely do they have a significant effect. Specification Point 3.37B - Understand that the incidence of mutations can be increased by exposure to ionising radiation (for example, gamma rays, x-rays and ultraviolet rays) and some chemical mutagens (for example, chemicals in tobacco). Complete set of Chapter 5 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.

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 3.8 - Understand how the structure of the male and female reproductive systems are adapted for their functions. Specification Point 3.9 - Understand the roles of oestrogen and progesterone in the menstrual cycle. Complete set of Chapter 5 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 4.18B - Understand the effects of deforestation, including leaching, soil erosion, disturbance of evapotranspiration and the carbon cycle, and the balance of atmospheric gases. Complete set of Chapter 6 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 1.52C - Know how to represent a metallic lattice by a 2-D diagram. Specification Point 1.53C - Understand metallic bonding in terms of electrostatic attractions. Specification Point 1.54C - Explain typical physical properties of metals, including electrical conductivity and malleability. Complete set of Chapter 3 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 2.22C - Know that most metals are extracted from ores found in the Earth’s crust and that unreactive metals are often found as the uncombined element. Specification Point 2.23C - Explain how the method of extraction of a metal is related to its position in the reactivity series, illustrated by carbon extraction for iron and electrolysis for aluminium. Specification Point 2.24C - Be able to comment on a metal extraction process, given appropriate information. Specification Point 2.25C - Explain the uses of aluminium, copper, iron and steel in terms of their properties. Specification Point 2.26C - Know that an alloy is a mixture of a metal and one or more elements, usually other metals or carbon. Specification Point 2.27C - Explain why alloys are harder than pure metals. Complete set of Chapter 4 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 1.25 - Understand how to write word equations and balanced chemical equations (including state symbols). Specification Point 1.26 - Calculate relative formula masses (including relative molecular masses) from relative atomic masses. Specification Point 1.27 - Know that the mole is the unit for the amount of a substance. Specification Point 1.28 - Understand how to carry out calculations involving amount of substance, relative atomic mass and relative formula mass. 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.

Powerpoint lecture 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 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.19C - Know that a reversible reaction can reach dynamic equilibrium in a sealed container. Specification Point 3.20C - Know that at dynamic equilibrium the forward and reverse reactions occur at the same rate and the concentrations of reactants and products remain constant. Specification Point 3.21C - Understand why a catalyst does not affect the position of equilibrium in a reversible reaction. Specification Point 3.22C - Know the effect of changing either temperature or pressure on the position of equilibrium in a reversible reaction. Complete set of Chapter 6 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 4.5.4.1 - Control and coordination regarding plant hormones. Required Practical 8 - Investigating the effect of light on the growth of newly germinated seedlings. Specification Point 4.5.4.2 - Use of plant hormones. Complete set of Chapter 5 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.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 4.38C - Know that esters contain the functional group -COO-. Specification Point 4.39C - Know that ethyl ethanoate is the ester produced when ethanol and ethanoic acid react in the presence of an acid catalyst. Specification Point 4.40C - Understand how to write the structural and displayed formulae of ethyl ethanoate. Specification Point 4.41C - Understand how to write the structural and displayed formulae of an ester, given the name or formula of the alcohol and carboxylic acid from which it is formed and vice versa. Specification Point 4.42C - Know that esters are volatile compounds with distinctive smells and are used as food flavourings and in perfumes. Specification Point 4.43C - Practical: prepare a sample of an ester such as ethyl ethanoate. Complete set of Chapter 7 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 4.7 - Know that crude oil is a mixture of hydrocarbons. Specification Point 4.8 - Describe how the industrial process of fractional distillation separates crude oil into fractions. Specification Point 4.9 - Know the names and uses of the main fractions obtained from crude oil. Specification Point 4.10 - Know the trend in colour, boiling point and viscosity of the main fractions. Complete set of Chapter 7 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 4.19 - Know the general formula for alkanes. Specification Point 4.20 - Explain why alkanes are classified as saturated hydrocarbons. Specification Point 4.21 - Understand how to draw the structural and displayed formulae for alkanes with up to five carbon atoms in the molecule, and to name the unbranched-chain isomers. Specification Point 4.22 - Describe the reactions of alkanes with halogens in the presence of ultraviolet radiation, limited to mono-substitution. Specification Point 4.23 - Know that alkenes contain a particular functional group (C=C). Specification Point 4.24 - Know the general formula for alkenes. Specification Point 4.25 - Explain why alkenes are classified as unsaturated hydrocarbons. Specification Point 4.26 - Understand how to draw the structural and displayed formulae for alkenes with up to four carbon atoms in the molecule, and name the unbranched-chain isomers. Specification Point 4.27 -Describe the reactions of alkenes with bromine to produce dibromoalkanes. Specification Point 4.28 - Describe how bromine water can be used to distinguish between an alkane and an alkene. Complete set of Chapter 7 Lectures are available.

Powerpoint lecture covering the following in a modern, concise format: Specification Point 3.7 - Use the relationship between frequency and wavelength in different contexts including sound waves and electromagnetic waves. Specification Point 3.8 - Explain why there is a change in the observed frequency and wavelength of a wave when its source is moving relative to an observer, and that this is known as the Doppler effect. Specification Point 3.10 - Know that light is part of a continuous electromagnetic spectrum that includes radio, microwave, infrared, visible, ultraviolet, x-ray and gamma ray radiations and that all these waves travel at the same speed in free space. Specification Point 3.11 - Know the order of the electromagnetic spectrum in terms of decreasing wavelength and increasing frequency, including the colours of the visible spectrum. Specification Point 3.12 - Explain some of the uses of electromagnetic radiations. Specification Point 3.13 - Explain the detrimental effects of excessive exposure of the human body to electromagnetic waves and describe simple protective measures against the risks. Complete set of Chapter 3 Lectures are available.