Infectious and non-infectious diseases (CIE A-level Biology)

This lesson explains the difference between non-infectious and infectious diseases and names the pathogens that cause examples of the latter. The PowerPoint and accompanying worksheets have been primarily designed to cover points 10.1 (a & b) of the CIE A-level Biology specification but as this is the first lesson in topic 10, links to upcoming topics such as the immune response and vaccinations are introduced.

The lesson begins with a challenge where the students have to use descriptions to recognise CHD, HIV and TB as diseases that are commonly referred to by their abbreviations. This leads into a description of the meaning of disease before the students are challenged to use any prior knowledge of this topic to recognise that CHD is an examples of a non-infectious disease whereas HIV and TB are examples of infectious diseases. Specification point 10.1 (a) states that students should know about sickle cell anaemia and lung cancer so the next section of the lesson focuses on the key details of these diseases and when considering the former, their knowledge of gene mutations, protein synthesis and haemoglobin is tested.

viruses - HIV/AIDS, influenza, measles, smallpox
bacteria - TB, cholera,
protoctista - malaria

The infectious diseases shown above are covered by the remainder of this lesson and the differing mechanisms of action of these three types of pathogens are discussed and considered throughout. For example, time is taken to describe how HIV uses a glycoprotein to attach to T helper cells whilst toxins released by bacteria damage the host tissue and the Plasmodium parasite is transmitted from one host to another by a vector to cause malaria.

The accompanying worksheets contain a range of exam-style questions, including a mathematical calculation, and mark schemes are embedded into the PowerPoint to allow students to immediately assess their understanding.