Krebs cycle (WJEC A-level biology)

This lesson guides the students through the stages of the Krebs cycle, describing how ATP and reduced NAD are produced and carbon dioxide released. The PowerPoint and accompanying resource have been planned to cover the content of topic 3 point [c] of A2 unit 3 as set out in the WJEC A-level biology specification.

As shown on the cover image, the lessons starts with a challenge, where students are tasked with recognising that the connection is biological cycles. A prior knowledge check is used to challenge their recall of the mitochondria as the site of aerobic respiration and then to identify the matrix as the site for this particular stage. Moving forwards, the 6 steps of the cycle are explored, and time is taken to consider how dehydrogenation and decarboxylation lead to the reduction of NAD and the release of carbon dioxide, and how ATP is produced by substrate-level phosphorylation. A series of exam-style questions check their understanding, and this includes a link to the next stage and the electron transport system. The answers to all knowledge checks are embedded into the PowerPoint to allow the students to assess their progress.