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SNAB A2 topics

Salters-Nuffield Advanced Biology for Edexcel A2 Biology

Topics and topic summaries for the Salters-Nuffield Advanced Biology context-led version of the Edexcel GCE Biology specification.

Topic 5 On the wild side

In the context of climate change the topic considers aspects of ecology, physiology, evolution and conservation. This topic builds an appreciation that photosynthesis is the primary process underpinning the majority of ecosystems, and provides students with an understanding of how ecosystems work. The topic continues by looking at whether climate change will lead to extinction of species or evolution by natural selection, and looks at the evidence for global warming and its effects on plants and animals. By the end of the topic, students should appreciate how scientific understanding can make us aware of our responsibilities as stewards of the environment.

Topic 6 Infection, immunity and forensics

This topic starts by looking at how forensic pathologists use a wide variety of analytical techniques to determine the identity of a person or other animal, and to establish the time and cause of death of organisms, including humans. It then considers how bacteria and viruses use a variety of routes into their hosts, and how hosts have evolved barriers and internal mechanisms to combat infections. This topic also investigates the evolutionary battles that take place between invading pathogens and their hosts.

Topic 7 Run for your life

This topic is centred on the physiological adaptations that enable animals and humans, particularly sports people, to undertake strenuous exercise. It explores the links between an animal's physiology and its performance. The topic summarises the biochemical requirements for respiration, and looks at the links between homeostasis, muscle physiology and performance. It ends by looking at how medical technology is enabling more people to participate in sport, and by raising the issue as to whether the use of performance-enhancing substances by athletes can be justified.

Topic 8 Grey matter

The scene is set by considering how the working of the nervous system enables us to see. Brain imaging and the regions of the brain are considered. The topic also demonstrates how an understanding of brain structure and functioning is relevant to such issues as the response to stimuli, the development of vision, and learning. It investigates how imbalances in brain chemicals may result in conditions such as Parkinson's disease, and its treatment with drugs is investigated. Students discuss the ethical issues raised by the Human Genome Project, and the risks and benefits of using genetically modified organisms.